Draft Standard for the Calculation and Labeling of the Energy Performance of Low-Rise Residential Buildings using the HERS Index Comments Submitted

The following comments have been submitted:

Comment #1

Page Number: 1
Comment Type: General

Comment:

Enough regulation...STOP...You change them faster than anyone can learn them...STOP

Even the info you ask preliminary to the survey is not necessary as yiou will do NOTHING with it.

STOP REGULATING!!!

Proposed Change:

QUIT it!!!

Response:

Rejected. The comment made by this commentator is not specific to BSR/RESNET Standard 301-201x.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #2

Page Number: 61
Paragraph / Figure / Table / Note: 6.3.4
Comment Type: Technical

Comment:

Section 6 and the Normative annexes of the proposed standard include software varification criteria for all software tests exceptfor the ASHRAE Standard 140 tests. Rather than reference an outdated source (HERS BESTEST) for these software verification test criteria, the standard should include the criteria directly in the standard. A number of editorial changes are also proposed to specify the date of the ASHRAE Standard and to clean up the existing language to include the verification criteria for these tests.

Proposed Change:

6.3.4. ANSI/ASHRAE Standard 140, Class II, Tier 1 Tests. ASHRAE Standard 140, Class II Tests were developed from the HERS BESTEST1 for testing the accuracy of simulation software for predicting building loads. The ANSI/ASHRAE Standard 140-2011, Class II, Tier 1 test procedure has been adopted by RESNET and is a requirement for all software programs to be accredited. The acceptance criteria for this test suite are as specified in Tables 4-1 and 4-2 of the original HERS BESTEST document “Home Energy Rating System Building Energy Simulation Test (HERS BESTEST) – Volume 2, Tier 1 Test Reference Results” by R. Judkoff and J. Neymark, as published by the National Renewable Energy Laboratory, Golden, Colorado, Report No. NREL/TP-472-7332b, November 1995. This document may be found online at: http://www.nrel.gov/docs/legosti/fy96/7332b.pdf developed in accordance with Annex 22 of ANSI/ASHRAE Standard 140-2011and are as follows:

Annual Heating Loads: 
Colorado Springs, CO
Heating    range max    range min
L100AC             79.48            48.75
L110AC           103.99            71.88
L120AC             64.30            37.82
L130AC             53.98            41.82
L140AC             56.48            43.24
L150AC             71.33            40.95
L155AC             74.18            43.53
L160AC             81.00            48.78
L170AC             92.40            61.03
L200AC           185.87          106.41
L202AC           190.05          111.32
L302XC             90.52            52.66
L304XC             75.32            43.91
L322XC           118.20            68.35
L324XC             80.04            44.01

Annual Heating Load deltas: 
Colorado Springs, CO
Heating                  range max          range min
L110AC-L100AC           28.12                  19.37
L120AC-L100AC            -7.67                -18.57
L130AC-L100AC            -5.97                -27.50
L140AC-L100AC            -4.56                -24.42
L150AC-L100AC            -3.02                -12.53
L155AC-L150AC             6.88                   -1.54
L160AC-L100AC             5.10                   -3.72
L170AC-L100AC           17.64                    7.12
L200AC-L100AC         107.66                 56.39
L202AC-L200AC             9.94                   -0.51
L302XC-L100AC           14.50                   -3.30
L302XC-L304XC           17.75                    5.66
L322XC-L100AC           39.29                  15.71
L322XC-L324XC           38.27                  20.21


Annual Cooling Loads: 
Las Vegas, NV
Cooling    range max    range min
L100AL             64.88            50.66
L110AL             68.50            53.70
L120AL             60.14            47.34
L130AL             45.26            32.95
L140AL             30.54            19.52
L150AL             82.33            62.41
L155AL             63.06            50.08
L160AL             72.99            58.61
L170AL             53.31            41.83
L200AL             83.43            60.25
L202AL             75.96            52.32

Annual Cooling Load deltas: 
Las Vegas, NV
Cooling                range max    range min
L110AL-L100AL             7.84             -0.98
L120AL-L100AL             0.68             -8.67
L130AL-L100AL         -13.71           -24.40
L140AL-L100AL         -27.14           -38.68
L150AL-L100AL          20.55               8.72
L155AL-L150AL           -9.64           -22.29
L160AL-L100AL          12.28               3.88
L170AL-L100AL           -4.83           -15.74
L200AL-L100AL          21.39               6.63
L200AL-L202AL          14.86               2.03

 

Response:

Rejected.  Software accreditation and software verification testing will be removed from this standard because it is not included in the Title, Purpose and Scope of the BSR/RESNET Standard 301-201x.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #3

Page Number: 15
Paragraph / Figure / Table / Note: Table 4.2.2.1
Comment Type: Technical

Comment:

The proposed change is to incorporate the Board of Director's Interpretation on service hot water heaters into Standard 301 adn remove it from the standard interpretation list.

Proposed Change:

[Add additional footnote (p)and strike extraneous “Same as Rated Home” item under Rated Home column]

Building Component

HERS Reference Home

Rated Home

Service water heating systems (h) (m) (p)

Fuel type:  same as Rated Home

Efficiency

Electric: EF = 0.97 - (0.00132 * store gal)

Fossil fuel: EF = 0.67 - (0.0019 * store gal)

Use (gal/day):  30*Ndu + 10*Nbr
where Ndu = number of dwelling units

Tank temperature:  120 F

Same as Rated Home (m)
 

Same as Rated Home

Same as Rated Home

Same as Rated Home

Same as HERS Reference Home
 

Same as HERS Reference Home

 

(p)     Raters are expected to obtain Energy Factors (EF) for domestic hot water equipment directly from manufacturer’s literature or from AHRI directory for equipment being used. For instances where a manufacturer provided or AHRI published EF does not exist (e.g. commercial water heaters), the rater shall use the guidance provided here to determine the effective EF of ht water heater.

        i.            For conventional residential (oil, gas and electric) water heaters or heat pump, use default EF values provided in Table 4.4.2(3) for age-based efficiency or Table 4.4.2(4) for non-age-based efficiency.

      ii.            For commercial water heaters used in residential applications, one of the following approaches shall be followed to determine the EF for a particular piece of equipment.

a.       Use the commercial hot water system calculator posted on the RESNET web site.

b.      Use Table C404.2 Minimum Performance of Water Heating Equipment in the 2012 International Energy Conservation Code to find the minimum requirement for the type of water heater.

Response:

Accepted as modified. Proposed changes will be made to the draft.

Comment #4

Page Number: 2
Paragraph / Figure / Table / Note: Definitions
Comment Type: Technical

Comment:

The definition of Conditined Floor Area should be modified to reflect the Board of Director's Interpretation on Conditioned Floor Area

Proposed Change:

Conditioned fFloor aArea (CFA) – The finished floor area in square feet of a home that is conditioned by heating or cooling systems, measured in accordance with ANSI Standard Z765-2003 with exceptions as specified in Appendix A of the RESNET Mortgage Industry National Home Energy Rating Systems Standards.

CFA includes:

                    i.            All finished space within the conditioned space boundary (i.e. within the insulated envelope), regardless of HVAC configuration. CFA includes

                  ii.            Unfinished spaces that are directly conditioned (i.e. having fully ducted HVAC supply or other intentional heating or cooling source).

CFA does not include:

                    i.            Spaces such as insulated basements or attics that are unfinished and not directly conditioned

                  ii.            Heated garages.

Response:

 

Accepted as modified (see also comment #72). The definition of Conditioned Floor Area (CFA) will be modified as follows:

 

Conditioned Floor Area (CFA) – The projected floor area of the Conditioned Space within a building measured in accordance with ANSI Standard Z765-2012 with exceptions as specified in Appendix A of the Mortgage Industry National Home Energy Rating Systems Standards.

Comment #5

Page Number: 13 and following
Paragraph / Figure / Table / Note: Table 4.2.2(1)
Comment Type: Technical

Comment:

RESNET Board of Directors Interpretations 2006-003, 2006-004 and 2007-002 all address air exchange rate and mechanical ventilation in the Reference and Rated Homes. Additionally, ASHRAE has recently adopted addenda 'n' and 'r' to ANSI/ASHRAE Standard 62.2-2010, which alter the methods by which mechanical ventilation requirements are calculated, considering natural infiltration in combination with mechanical ventilation. This proposed change brings the RESNET Draft Standard 301 into alignment with these recent changes, updates all references to the ASHRAE Handbook of Fundamentals to the most recent edition and incorporates the above Board of Directors Interpretations on this matter.

Proposed Change:

[Modify Air exchange rate and Mechanical ventilation in Table 4.2.2(1) and Table notes (d), (e) and (f) as follows:]

 

Air exchange rate

Specific Leakage Area (SLA) (d) = 0.00036 (assuming no energy recovery)

For residences that are not tested, the same as the HERS Reference Home

For residences without mechanical ventilation systems that are tested in accordance with ASHRAE Standard 119, Section 5.1Chapter 802 of the RESNET Standards, without mechanical ventilation systems, the measured air exchange rate (e) but not less than 0.30 ach

For residences with mechanical ventilation systems that are tested in accordance with ASHRAE Standard 119, Section 5.1 Chapter 802 of the RESNET Standards, with mechanical ventilation systems, the measured air exchange rate (e) combined with the mechanical ventilation rate,(f) which shall not be less than 0.010.03 x CFA + 7.5 x (Nbr+1) cfm

Mechanical ventilation:

None, except where a mechanical ventilation system is specified by the Rated Home, in which case:

Annual vent fan energy use:

kWh/yr = 0.03942*CFA  + 29.565*(Nbr+1) (per dwelling unit)0.5*(supVfan + exhVfan)*8.76

where:

CFA = conditioned floor area

Nbr = number of bedrooms

supVfan = cfm of supply ventilation fan

exhVfan = cfm of exhaust ventilation fan

where supVfan and exhVfan are calculated in accordance with ANSI/ASHRAE Standard 62.2-2010, addendum ‘r’

Same as Rated Home

 

 

 

Same as Rated Home

 

 

(d) Where Effective Leakage Area (ELA) is defined in accordance with Section 5.14.12 of ASHRAE Standard 11962.2-2010, addendum ‘r’ and where SLA = ELA / CFA (where ELA and CFA are in the same units). Either hourly calculations using the procedures given in the 20012009 ASHRAE Handbook of Fundamentals, Chapter 2616, page 26.2116.23, equation 40(48) (Sherman-Grimsrud model) using Shelter Class 4 or calculations yielding equivalent results shall be used to determine the energy loads resulting from air exchange.

 

(e)  Tested envelope leakage shall be determined and documented by a Certified Rater using the on-site inspection protocol as specified in Appendix ASection 802, Mortgage Industry National Home Energy Rating Systems Standards. under “Blower Door Test.”  Either hourly calculations using the procedures given in the 20012009 ASHRAE Handbook of Fundamentals, Chapter 2616, page 26.2116.23, equation 40(48) (Sherman-Grimsrud model) using Shelter Class 4 or calculations yielding equivalent results shall be used to determine the energy loads resulting from air exchange.

 

(f)  The combined air exchange rate for infiltration and mechanical ventilation shall be determined in accordance with equation 43(51) of 20012009 ASHRAE Handbook of Fundamentals page 26.2416.25 in combination with the ”Whole-house Ventilation” Section 4 provisions of 2001 ANSI/ASHRAE Standard 62.2-2010, addendum ‘r’ Handbook of Fundamentals, page 26.19 for intermittent mechanical ventilation.

Response:

Accepted as modified. Proposed changes per comment #42 will be made to the draft.

Comment #6

Page Number: 15 and 19
Paragraph / Figure / Table / Note: Table 4.2.2(1)
Comment Type: Technical

Comment:

Board of Directors Interpretation 2006-002 addresses Thermal distribution systems in Table 4.2.2(1) and Table note (n) in an attempt to clarify and simplify the ASHRAE Standard 152 distribution system testing procedures. Since the adoption of this Interpretation by the Board, Section 803 of the RESNET Standards has effectively superseded the Standard 152 distribution system testing procedures. This proposed change to the RESNET Draft Standard 301 replaces the reference to ASHRAE Standard 152 with reference to Section 803 of the RESNET Standards. Additionally, there have been numerous complaints regarding the interpretation, use and misuse of Table 4.2.2(4), so this proposed change also deletes this table in its entirety, specifying the DSE for ductless and hydronic distribution systems directly in Table 4.2.2(1) instead.

Proposed Change:

[Modify Table 4.2.2(1) as follows:]

Thermal distribution systems:

A thermal distribution system efficiency (DSE) of 0.80 shall be applied to both the heating and cooling system efficiencies.

 

As specified by Table 4.2.2(4)For forced air distribution systems:  same as Reference Home, except when tested in accordance with ASHRAE Standard 152-2004Section 803 of the RESNET Standards (n), and then either calculated through hourly simulation or calculated in accordance with ASHRAE Standard 152-2004 with the ducts located and insulated as in Rated Home

For ductless distribution systems:  DSE=1.00

For Hydronic distribution systems:  DSE=1.00

 

[Modify Table not (n) as follows:]

(n)  Tested duct leakage shall be determined and documented by a Certified Rater using the on-site inspection protocol as specified in Appendix A under “Air leakage (ducts)”Section 803of the Mortgage Industry National Home Energy Rating System Standards (the RESNET Standards).

 

[Delete Table 4.2.2(4) and its notes in their entirety]

Table 4.2.2(4).         Default Distribution System Efficiencies for
Inspected Systems (a)

Distribution System Configuration and Condition:

Forced Air Systems

Hydronic Systems (b)

Distribution system components located in unconditioned space

0.80

0.95

Distribution systems entirely located in conditioned space (c)

0.88

1.00

Proposed “reduced leakage” with entire air distribution system located in the conditioned space (d)

0.96

 

Proposed “reduced leakage” air distribution system with components located in the unconditioned space(d)

0.88

 

“Ductless” systems (e)

1.00

 

 

Table 4.2.2(4) Notes:

 

(a)  Default values given by this table are for distribution systems as rated, which meet minimum IECC 2000 requirements for duct system insulation.

 

(b)  Hydronic Systems shall mean those systems that distribute heating and cooling energy directly to individual spaces using liquids pumped through closed loop piping and that do not depend on ducted, forced air flows to maintain space temperatures.

 

(c)  Entire system in conditioned space shall mean that no component of the distribution system, including the air handler unit or boiler, is located outside of the conditioned space boundary.

 

(d) Proposed “reduced leakage” shall mean substantially leak free to be leakage of not greater than 3 cfm to outdoors per 100 square feet of conditioned floor area and not greater than 9 cfm total air leakage per 100 square feet of conditioned floor area at a pressure differential of 25 Pascal across the entire system, including the manufacturer’s air handler enclosure. Total air leakage of not greater than 3 cfm per 100 square feet of conditioned floor area at a pressure difference of 25 Pascal across the entire system, including the manufacturer’s air handler enclosure, shall be deemed to meet this requirement without measurement of air leakage to outdoors. This rated condition shall be specified as the required performance in the construction documents and requires confirmation through field-testing of installed systems as documented by a Certified Rater.

 

(e)        Ductless systems may have forced airflow across a coil but shall not have any ducted airflows external to the manufacturer’s air handler enclosure.

Response:

Accepted.  The proposed language will be incorporated into BSR/RESNET Standard 301-201x.

Comment #7

Page Number: na
Comment Type: General

Comment:

 

My comments are limited to just energy performance related to the plumbing system itself and, more specifically to what’s between the water heater and the hot water fixtures – namely the pipe itself. 

ENERGY STAR has delivered ever-increasing performance with water heating products. WaterSense has done a good job, thus far, with hot water fixtures. There appears to be no initiative to address energy efficiency with respect to the pipe in between hence defining the plumbing system. In short, I believe an opportunity is being ignored. 

Below is from a parametric analysis I did during 2009-2011 on 8700 homes with standard plumbing; 3600 homes with dedicated hot water recirculation loops incorporating timer pumps in terms of wasted energy and wasted water. Waste was defined as “water down the drain which had previously been heated while waiting for hot water for current use.” The values are community specific but useful for comparative purposes. The values are annualized and represent the waste in the plumbing system for one housing unit. 

                                                                      Wasted energy, $   Wasted water, gal   CO2 emissions, lb 

Standard plumbing 
EWH                                                                    $171                           8800                      1700
GWH                                                                     109                            8800                       780 

Dedicated loop/timer (weighted avg) 
EWH                                                                      384                            5000                     3780
GWH                                                                      253                            5000                     1810 

Demand controlled pump 
EWH                                                                        72                            1200                       700 
GWH                                                                        46                            1200                       330 

The table above reeks of opportunity for demand controlled pump solutions especially as retrofits for standard plumbed existing homes of which 90M owner occupied currently exists today. 

As to the dedicated loop/timer pump systems for this community, it has now been recognized that good intentions resulted in unintended consequences and revised plumbing codes are under review. 

As to new residential construction a number of analyses have been conducted which clearly demonstrate a demand controlled pump including installation and included in a new mortgage will result in a net decrease in monthly home ownership expenses due to the reduced water and energy expenses provided by a demand controlled pump installation. Take this one step further: why wouldn't a government insured new home mortgage, via Freddie Mac or Fannie Mae, not require a demand controlled pump in such a new insured mortgage?   Why would this be important?  DOE and EPA, both, are working on energy (and water) reduction policy; so why shouldn't a quasi-federal agency also be involved?

In summary: there is low hanging fruit with respect to addressing the plumbing system. Energy is energy whether saved by a more efficient dishwasher, refrigerator, HVAC and properly designed plumbing system. 

My apologies for the length of the comment.

 
Response:

Rejected. The comment does not make a proposed change to BSR/RESNET Standard 301-201x.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #8

Page Number: 11
Comment Type: General

Comment:

Calculating the HERS score must include duct testing and infiltration testing via blower door. The 2012 codes require such testing and an accurate HERS score needs to require field testing to be a valid indicator of energy efficiency use for comparison purposes.

Response:

Accepted. BSR/RESNET Standard 301-201X will be modified to require testing of envelope leakage and air distribution system leakage for Confirmed Ratings. The definition of a confirmed rating will be revised as follows.

“Confirmed Rating – A Rating Type accomplished using the actual data gathered from an on-site audit inspection and, if required, performance testing of the physical building and its installed systems and equipment including, at a minimum, air distributions system testing and envelope leakage testing.

Comment #9

Page Number: 1
Comment Type: General

Comment:

My comment is on the label for certifing the energy performance of a home. In discussions with builders, remodelers, and other profesionals in the residential construction industry, they are all asking for the same thing when it comes to a label - predicted annual energy costs, and annual energy consumption information compared to a baseline. People in the environmental industry would like to see a carbon dioxide equivalent figure as well, which I feel is worth including.  

In addition, above-code programs like LEED, which compare not just the energy performance of a house to the same house built to local code, but one home to another, see an annual energy metric (or absolute energy metric) as better suiting our needs. Even EPA went away from the static HERS Index target for ENERGY STAR for Homes. I fervently believe it is in RESNET's best interest to create a calculation methodology based on annual energy consumption to complement the HERS Index, which can be done using the same inputs as the HERS Index, just a different output.

Proposed Change:

Create an annual energy metric (or absolute energy metric) for labeling new and existing homes.

Create protocols for including the consumption of pools, spas, heated driveways, heated garages and other large permanently installed energy users that currently aren't included in the HERS Index and annual energy metric.

Response:

Noted. BSR/RESNET Standard 301-201x already requires the reporting of annual energy use and annual energy cost so it is not clear what change the commentator is seeking in this regard. The creation of protocols for evaluating the energy consumption of additional components of a home is beyond the scope of this public review but rather is an on-going effort within the energy rating community, which when completed will likely become a proposed revision to this Standard.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #10

Page Number: Entire document
Comment Type: General

Comment:

This standard is proposing the use of Source Energy efficiency at a predetermined efficiency level. We feel using source energy is very biased and inaccurate and will unfairly rate standard electric heating options as being inefficient causing an unacceptable HERS score.

Electric generation comes from many forms including nuclear, fuel, coal, natural gas, wind, hydro, solar, biomass, etc. The generation mix varies from region to regions, state to state and even county to county in some areas. In some areas, nearly 100% of power is generated with non-fossil sources and the efficiency is very high. Using an average national efficiency for rating HVAC equipment would at best be highly inaccurate. Additionally, there is a rapidly growing amount of renewable energy in our country and electric heating systems provide a very efficient means of utlizing this power while also providing other critical needs of the electric grid.

We propose that appliance energy efficiency rating be used at the point of energy delivery (site energy efficiency). The consumer can control and maximize efficiency at this level; however, can not control how energy production occurs outside his home. This also would create a level and fair basis for all HVAC and general purpose appliances in the home.

Proposed Change:

Use site energy efficiency references for HVAC appliances rather than source energy efficiency.

Response:

Rejected. While alternative rating methods may be available, the rating method proposed by this comment is not considered persuasive.  The commentator’s proposed change to the rating method neither improves on the proposed Standard nor does it offer evidence that the proposed Standard is technically deficient.

There is a long history of argument between the electric industry and the natural gas industry about how energy use should be counted. The electric industry favors counting energy units based site energy and the natural gas industry favors counting energy units based source (or primary) energy. In 1999, the method that RESNET uses was developed to solve a number of problems related to “rating’ the energy performance of homes. It is called the normalized modified end use loads method (see http://www.resnet.us/professional/ratings/ratingmethod). It relies on using the sum of building end use loads for the Reference Home as the denominator of the “scoring fraction.” It then normalizes the energy end uses of the Rated Home with respect to the minimum and best available efficiencies for electric and natural gas equipment technologies. The method is not completely suitable to either the electric industry or the gas industry and, thus, we have received public comments from both parties to change the rating method to an alternative method that would advantage their particular industry in the marketplace. While the normalized modified end use loads (nMEUL) method may be difficult to explain in lay terms, it has been in effect and widely used by RESNET since 1999 when it was first adopted by the National Association of State Energy Officials (NASEO).

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #11

Page Number: 14
Paragraph / Figure / Table / Note: 4.2.2(1) and 4.2.2(1a)
Comment Type: Technical

Comment:

Currently air source heat pumps are used as the base reference for electric heating systems. Using this approach discriminates against many very beneficial and effiecient electric heating systems which benefit consumers, utilities and society. We propose that standard electric resistance heating systems be used as the baseline (including electric thermal storage devices) with appliance efficiency requirements of 100%.

Proposed Change:

 

 

Table 4.2.2(1)

Electric: air source heat pump electric resistance heat in accordance with Table 4.2.2(1a)

 

 Table 4.2.2(1)

 

7.7 HSPF air source heat pump electric resistance heating 100% eff.

 

Response:

Rejected. While alternative rating methods may be available, the rating method proposed by this comment is not considered persuasive.  The commentator’s proposed change to the rating method neither improves on the proposed Standard nor does it offer evidence that the proposed Standard is technically deficient.

There is a long history of argument between the electric industry and the natural gas industry about how energy use should be counted. The electric industry favors counting energy units based site energy and the natural gas industry favors counting energy units based source (or primary) energy. In 1999, the method that RESNET uses was developed to solve a number of problems related to “rating’ the energy performance of homes. It is called the normalized modified end use loads method (see http://www.resnet.us/professional/ratings/ratingmethod). It relies on using the sum of building end use loads for the Reference Home as the denominator of the “scoring fraction.” It then normalizes the energy end uses of the Rated Home with respect to the minimum and best available efficiencies for electric and natural gas equipment technologies. The method is not completely suitable to either the electric industry or the gas industry and, thus, we have received public comments from both parties to change the rating method to an alternative method that would advantage their particular industry in the marketplace. While the normalized modified end use loads (nMEUL) method may be difficult to explain in lay terms, it has been in effect and widely used by RESNET since 1999 when it was first adopted by the National Association of State Energy Officials (NASEO).

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #12

Page Number: New normative annex
Comment Type: Technical

Comment:

We propose for the RESNET Standard 301 (RESNET PDS 301-01) to include a new normative annex for the 2009 IECC Standard Design Auto-Generation Tests in addition to the existing Annex C – 2006 IECC Standard Design Auto-Generation Tests. The justification for the need of the proposed annex is that many states now have adopted the 2009 IECC as their energy code for new residential construction; and consequently, there are IECC performance path calculation tools available that provide an option for 2009 IECC code compliance.

Proposed Change:

2009 IECC Standard Design Auto-Generation Tests

(Normative)

 

This normative Annex contains the Reference Home auto-generation test suite for 2009 IECC performance compliance tools. The test cases in this proposed test suite are designed to verify that software tools automatically generate accurate Standard Reference Designs given only the building information from the Proposed Homes.

 

  1. Minimum Reporting Requirements

 

Software tools applying for verification shall provide evidence that their software meets the requirements of this test suite.  The software tool provider or software vendor is responsible for producing the documentation needed to show that the software has been verified through this test suite.  In some cases, the data needed to verify accuracy is of no interest or value to the end-user of the software, but in any case, the software tool must generate it.  At a minimum, software tools applying for accreditation must report the following values for the Reference Home:

 

  1. Areas and overall U-factors (or R-values in the case of slab-on-grade construction) for all building components, including ceilings, walls, floors, windows (by orientation) and doors.
  2. Overall solar-heat gain coefficient (SHGCo)[1] of the windows during heating.
  3. Overall solar-heat gain coefficient (SHGCo) of the windows during cooling.
  4. Wall solar absorptance and infrared emittance
  5. Roof solar absorptance and infrared emittance
  6. Total internal gains to the home (Btu/day)
  7. Specific leakage area (SLA) for the building, by zone or as SLAo[2], as appropriate
  8. Attic net free ventilation area (ft2)
  9. Crawlspace net free ventilation area (ft2), if appropriate
  10. Exposed masonry floor area and carpet and pad R-value, if appropriate
  11. Heating system labeled ratings, including AFUE, COP, or HSPF, as appropriate.
  12. Cooling system labeled ratings, including SEER or EER, as appropriate.
  13. Thermostat schedule for heating and cooling
  14. Air distribution system characteristics, including locations of all supply and return ducts and the air handler units, supply and return duct R-values, and supply and return duct air leakage values (in cfm25).[3]
  15. Mechanical ventilation kWh/yr, if appropriate

 

Software tools must have the ability to recreate or store the test case Standard Reference Designs as if they were Proposed Homes such that they also can be simulated and evaluated as the Proposed Homes.

 

  1. Auto-generation Test Case Descriptions

 

Test Case1. HERS BESTEST case L100 building configured as specified in the HERS BESTEST procedures, located in Baltimore, MD, including a total of 3 bedrooms and the following mechanical equipment: gas furnace with AFUE = 82% and central air conditioning with SEER = 16.0. 

 

Test Case 2.  HERS BESTEST case L100 configured on an un-vented crawlspace with R-7 crawlspace wall insulation, located in Dallas, TX, including a total of 3 bedrooms and the following mechanical equipment: electric heat pump with HSPF = 8.2 and SEER = 15.0.

 

Test Case 3.  HERS BESTEST case L304 in Miami, configured as specified in the HERS BESTEST procedures, located in Miami, FL, including a total of 2 bedrooms and the following mechanical equipment: electric strip heating with COP = 1.0 and central air conditioner with SEER = 17.0.

 

Test Case 4.  HERS BESTEST case L324 configured as specified as in the HERS BESTEST procedures, located in Colorado Springs, CO, including a total of 4 bedrooms and the following mechanical equipment:  gas furnace with AFUE = 95% and no air conditioning.

 

Test Case 5.  Recreate or store the Reference Homes created in Tests 1 through 4 as Rated Homes and simulate and evaluate them.

 

  1. Acceptance Criteria

 

Test Cases 1 – 4. 

 

For test cases 1 through 4 the values contained in Table C-1 shall be used as the acceptance criteria for software tool accreditation.  For Standard Reference Design building components marked by an asterisk (*), the acceptance criteria may include a range equal to ± 0.05% of the listed value.  For all other Reference Home components the listed values are exact.

 

Table C-1  Acceptance Criteria for Test Cases 1 – 4

 

Reference Home Building Component

Test 1

Test 2

Test 3

Test 4

Above-grade walls (Uo)

0.082

0.082

0.082

0.057

Above-grade wall solar absorptance (α)

0.75

0.75

0.75

0.75

Above-grade wall infrared emittance (ε)

0.90

0.90

0.90

0.90

Basement walls (Uo)

n/a

n/a

n/a

0.059

Above-grade floors (Uo)

0.047

0.047

n/a

n/a

Slab insulation R-Value

n/a

n/a

0

0

Ceilings (Uo)

0.030

0.035

0.035

0.030

Roof solar absorptance (α)

0.75

0.75

0.75

0.75

Roof infrared emittance (ε)

0.90

0.90

0.90

0.90

Attic vent area* (ft2)

5.13

5.13

5.13

5.13

Crawlspace vent area* (ft2)

n/a

10.26

n/a

n/a

Exposed masonry floor area * (ft2)

n/a

n/a

307.8

307.8

Carpet & pad R-Value

n/a

n/a

2.0

2.0

Door Area (ft2)

40

40

40

40

Door U-Factor

0.35

0.50

1.20

0.35

North window area* (ft2)

57.71

57.71

57.71

49.95

South window area* (ft2)

57.71

57.71

57.71

49.95

East window area* (ft2)

 57.71

57.71

57.71

49.95

West window area* (ft2)

 57.71

57.71

 57.71

49.95

Window U-Factor

0.35

0.50

1.20

0.35

Window SHGCo (heating)

0.34

0.34

0.34

0.34

Window SHGCo (cooling)

0.28

0.28

0.28

0.28

SLAo (ft2/ft2)

0.00036

0.00036

0.00036

0.00036

Internal gains* (Btu/day)

66,840

66,840

62,736

107,572

Labeled heating system efficiency rating

AFUE =
82%

HSPF =
8.2

HSPF =
7.7

AFUE =
95%

Labeled cooling system efficiency rating

SEER =
16.0

SEER =
15.0

SEER =
17.0

SEER =
13.0

Air Distribution System Efficiency

0.88

0.88

0.88

0.88

Thermostat Type

Manual

Manual

Manual

Manual

Heating thermostat settings

 72 F
(all hours)

 72 F
(all hours)

 72 F
(all hours)

 72 F

(all hours)

Cooling thermostat settings

 75 F

(all hours)

 75 F

(all hours)

 75 F

(all hours)

 75 F

(all hours)

 

  1. Test Case 5. 

 

Test case 5 requires that each of the Standard Reference Design for test cases 1-4 be stored or recreated in the software tool as Proposed Homes and simulated as any other rated home would be simulated.  If the resulting Proposed Home is correctly configured to be identical to its appropriate Standard Reference Design, code compliance calculations arising from normal operation of the software tool should produce virtually identical scoring criteria for both the Standard Reference Design and the Proposed Home for this round of tests.  For test case 5, the energy use e-Ratio shall be calculated separately from the simulation results for heating and cooling, as follows:

 

e-Ratio = (Proposed Home energy use) / (Standard Reference Design energy use)

 

Acceptance criteria for these calculations shall be ± 0.5% of 1.00.  Thus, for each of the preceding test cases (1-4), the e-Ratio resulting from these software tool simulations and the subsequent e-Ratio calculations shall be greater than or equal to 0.995 and less than or equal to 1.005.

 

 



[1]  The overall solar heat gain coefficient (SHGCo) of a fenestration is defined as the solar heat gain coefficient (SHGC) of the fenestration product taken in combination with the interior shade fraction for the fenestration.

[2]  SLAo is the floor-area weighted specific leakage area of a home where the different building zones (e.g. basement and living zones) have different specific leakage areas.

[3]  cfm25 = cubic feet per minute of air leakage to outdoors at a pressure difference between the duct interior and outdoors of 25 Pa.

 

Response:

Rejected. These provisions pertain to software verification testing which is being withdrawn from BSR/RESNET Standard 301-201x due to the fact that software testing and verification is not part of the authorized scope of BSR/RESNET Standard 301-201x.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #13

Page Number: 33
Paragraph / Figure / Table / Note: 4.3.3.2.8
Comment Type: Technical

Comment:

Heat pumps are becoming much more popular in northern climates where the heating load is greater than the cooling load. Sizing to the heating load in many situations will cause the heat pump to be grossly oversized for the cooling load. This will create comfort and dehumidification issues in the home and will erode efficiency during the cooling cycle.

Proposed Change:

 

4.3.3.2.8. Heat pump equipment shall be sized to equal the larger of the heating and cooling season calculations in accordance with these procedures.

Response:

Rejected. When heat pumps are sized to equal the cooling load, the heating load in many climates must be met by back-up strip resistance heating, which seriously degrades the performance of the heat pump. In fact, there is also strong evidence to indicate that heat pumps in cold climates should be sized somewhat larger than the recommendations of the AACA Manual J and Manual S recommendations to reduce back up strip resistance heating.


You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #14

Page Number: 4.3.3.2.4
Paragraph / Figure / Table / Note: 4.3.3.2.4
Comment Type: Technical

Comment:

This section refers to ASHRAE 62.2  2004.  I request the standard be updated to reflect the requirements of  ASHRAE 62.2.2010.

 

The 2004 standard was an interim standard. It has been replaced with the 2007 changes and again updated with the 2010 additions.

Response:

Accepted.  The commentator specified the incorrect paragraph, however, proposed ASHRAE Standard 62.2 update will be incorporated into section 4.3.3.2.5 of BSR/RESNET Standard 301-201x.

Comment #15

Page Number: 34
Paragraph / Figure / Table / Note: 4
Comment Type: General

Comment:

The minimum field verified standard does not include an actual Blower Door or Tracer Gas Test.  This omission of testing on a National Level, leaves this in the hands of the individual Provider.

I believe that every home rated should have a Blower Door Test completed. The actual CFM at 50 and the calulated volume of the house should be available to the rating process. These numbes should also be available along with the calculated ACH at 50 number on the Rating Label.

Allowing a home to go from a projected rating from plans to a confirmed rating without Diagnostic Testing simply means we are guessing.

I would like my profession to rise above, and actually test each and every rated house.

Response:

Accepted. BSR/RESNET Standard 301-201X will be modified to require testing of envelope leakage and air distribution system leakage for Confirmed Ratings. The definition of a confirmed rating will be revised as follows.

Confirmed Rating – A Rating Type accomplished using the actual data gathered from an on-site audit inspection and, if required, performance testing of the physical building and its installed systems and equipment including, at a minimum, air distributions system testing and envelope leakage testing.”

Comment #16

Page Number: various
Paragraph / Figure / Table / Note: various
Comment Type: Editorial

Comment:

The RESNET Technical Committee recently proposed, and the RESNET Board approved, an amendment to the RESNET Standards which allows ratings to be labeled “confirmed” without inputting actual field testing and inspecting findings back into the rating software.  So long as verification testing and inspection findings from the field are equal to or better than threshold specifications/minimum rated features for a worst-case rating analysis, the home can be labeled as “confirmed”.

The blending of all non-projected ratings under a single umbrella of “confirmed” will leave RESNET with no categorical distinction for a rating which is based on actual built conditions.  All ratings which actually represent the home being rated will simply be aggregated together with all the ratings that are worst-case and meet threshold testing and inspection requirements.  Looking down the road to a point in time when RESNET will want to mine the data in the RESNET Rating Registry (and no doubt third parties will be willing to pay RESNET for that same privilege), RESNET will have no easy way to cull the data which represents actual house performance and specification characteristics, data that will most certainly be of interest to RESNET and others.  Everything else, project and confirmed ratings, will be “close” to representing the actual house but only actual data is actual data.

Proposed Change:

Contents

(page i)

5.2. National Home Energy Performance Label Certifications ................... 52

5.2.1. Confirmed and Actual Ratings .................................................................52

3. Definitions

(page 2)

Actual Rating – A Rating Type accomplished using data gathered from an on-site audit inspection and, if required, performance testing of the physical building and its installed systems and equipment which is input into RESNET-accredited software to create a Rating which reflects the actual condition of the Rated Home.

(page 48)

5.1.2.1.2.3. For Confirmed, Actual, Sampled and Projected Ratings, estimated energy cost savings shall be calculated as follows –

(page 49)

5.1.2.2.2.3. For Confirmed, Actual, Sampled and Projected Ratings, estimated energy cost savings shall be calculated as follows –

(page 50)

5.1.4.2. Actual Rating. All Actual Ratings shall be for individual real properties where all Minimum Rated Features of the Rated Home are verified in the field through inspection and testing in accordance with the minimum requirements of Section 4.4 of this Standard and where field collected data is input into RESNET-accredited software.

5.1.4.1.2. All Actual Ratings shall be subject to the Quality Assurance requirements of Section 900 of the RESNET Mortgage Industry National Home Energy Rating Systems Standard.

5.1.4.2.2. All Actual Ratings shall use the field-verified Minimum Rated Feature data collected from field inspection and testing of the Rated Home and input the data into an accredited software rating tool to generate the actual Home Energy Rating for the Rated Home.

5.1.4.2.3. All Actual Ratings shall be submitted to the National RESNET Registry (see Section 5.3) for certification.

5.1.4.2.4. Following registration of Actual Ratings, the results of the Rating shall be certified in accordance with Section 5.2 of the Standard.

(page 52)

5.1.4.3.7. Upon completion of construction and field verification of the proposed specifications for all Minimum Rated Features of the Rated Home in accordance with Section 4.3.1 of this Standard (e.g. on-site visual inspections, on-site diagnostic test results or default values for envelope air leakage and distributions system efficiencies), and entry of either the field verified rated features or the threshold specification for a Worst-Case Analysis into an accredited rating tool, a pProjected Rating for the home shall become a Confirmed Rating for the home. If actual data for the Rated Home, reflecting the actual condition of the home, are entered into the rating tool, the Projected Rating for the home may become an Actual Rating for the home.

(page 52)

5.2.1. Confirmed and Actual Ratings.

5.2.1.1. All Confirmed and Actual Ratings shall be labeled using Rating Certification Form 5.2-1 provided by RESNET.

(page 54)

5.3.1.1. The Rated Home characteristics, including but not limited to the following:

a) Physical location of the home, including street address, city, state and zip code

b) IECC climate zone of the home

c) Certified Rater ID

d) Accredited Rating Provider ID

e) Date of the Rating

f) Status of the Rated Home (new or existing)

g) Rating Type for the home (confirmed, actual or sampled)

Response:

Accepted. BSR/RESNET Standard 301-201X will be modified to require testing of envelope leakage and air distribution system leakage for Confirmed Ratings. However, a Rating category of “Actual” will not be added to BSR/RESNET Standard 301-201x as it will not be required under these circumstances. The definition of a confirmed rating will be revised as follows.

“Confirmed Rating – A Rating Type accomplished using the actual data gathered from an on-site audit inspection and, if required, performance testing of the physical building and its installed systems and equipment including, at a minimum, air distributions system testing and envelope leakage testing.

Comment #17

Page Number: 22
Paragraph / Figure / Table / Note: 4.2.2.3
Comment Type: Editorial

Comment:

Insulated siding has become more popular as a form of continuous insulation. It would be appropriate to be included in this standard. Additional information on insulated siding including the new ASTM standard is available at http://www.insulatedsiding.info.

Proposed Change:

4.2.2.2.3. Insulation that does not cover framing members shall not be modeled as if it covers the framing. Insulated surfaces that have continuous insulation (i.e. rigid foam, fibrous batts, loose fill, or sprayed insulation, or insulated siding) covering the framing members shall be assessed and modeled according to Section 4.2.2.2 and combined with the cavity insulation, framing and other materials to determine the overall assembly R-value.

Response:

Accepted. The proposed change will be included in the final Committee draft of BSR/RESNET Standard 301-201x.

Comment #18

Page Number: 2
Paragraph / Figure / Table / Note: 3. Definitions
Comment Type: Technical

Comment:

Definition of CFA needs to align with Interpretation 2010-02

Response:

 

Accepted. Proposed changes will be made to the draft as per Public Comment #4 as reconciled with the SDC response to comment #72.

Comment #19

Page Number: 17
Paragraph / Figure / Table / Note: Table 4.2.2(1a) Notes (m)
Comment Type: Technical

Comment:

The de-rating of instantaneous DHW per Amendment 2011-03 should be referenced in this section

Response:

Accepted. Table 4.4.2(1a), Note (m) will be modified to reflect this comment.

Comment #20

Page Number: 21
Paragraph / Figure / Table / Note: 4.2.2.2.2. Insulation Assessment
Comment Type: Technical

Comment:

This section will need to be re-written to reflect the changes to Appendix A's insulation grading once that Amendment is adopted.

Response:

Rejected. Appendix A’s draft insulation grading language was erroneous and has been revised to reference the procedures provided in this proposed standard.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #21

Page Number: all - general
Comment Type: General

Comment:

Using the 2006 IECC as the baseline is problematic.  We suggest adjusting the baseline to the 2009 or 2012 IECC.  There are several items that are difficult to reconcile to the 2006 IECC baseline because of changes that have been made to the code.  For instance, as of the 2009 IECC there is no longer an allowance to trade off against outdated federal minimums for equipment efficiency [T4.2.2(1a)] .  The federal minimums are slated to be updated over the next several years.  Without a change this standard could quickly become obsolete.  Also the 2006 IECC did not have air leakage requirements as are now found in the more recent versions of the code. 

We would also like to see the use of general accepted engineering practices for framing factors [T4.2.2(6)].  The framing factors should be consistent with other code compliant software such as found in the Methodology for Developing the REScheckTM Software through Version 4.4.2.

 

[4.3.3.1.5, 4.3.3.2.6]  The assumption made in this section is that all windows have blinds.  This is a highly unlikely scenario and we suggest modeling as though blinds are not present.

Many of the existing home assumptions are artificially low.  We suggest updating the limits.

We highly encourage the collection and monitoring of data collected for HERS ratings.  We suggest a program similar to B3 which is produced by The Weidt Group for the entry and collection of such data.

Response:

Rejected. BSR/RESNET Standard 301-201x does not propose to provide a direct means of IECC code compliance. Rather, it intends to provide a Reference Home that is stable over time so as to reflect improvements in homes over time relative to the Standard Reference Design provisions of the 2006 IECC.


You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #22

Page Number: 33, 36, 70,
Paragraph / Figure / Table / Note: Default Air Leakage Rate for HERS Rating
Comment Type: Technical

Comment:

Should blower door testing be required for confirmed ratings?

It's complicated...

See EnergyLogic’s position on the matter http://nrglogicblog.com/?p=650&preview=true

Proposed Change:

It's a complicated matter that should be discussed.  The fact is RESNET doesn’t require blower door testing.  The reality is most providers require it, most raters do it.  These two discrepancies should be a concern to an industry pushing for consistency.

In short EnergyLogic's argument is that it's in the best interest of the industry that every home with a confirmed rating get an air leakage test assuming the house being tested is under safe conditions.

The full argument with a position paper on details on how this could be implemented with changes in the standard can be found here:

http://nrglogicblog.com/?p=650&preview=true

 

Response:

Accepted. BSR/RESNET Standard 301-201X will be modified to require testing of envelope leakage and air distribution system leakage for Confirmed Ratings. The definition of a confirmed rating will be revised as follows.


Confirmed Rating – A Rating Type accomplished using the actual data gathered from an on-site audit inspection and, if required, performance testing of the physical building and its installed systems and equipment including, at a minimum, air distributions system testing and envelope leakage testing.

Comment #23

Page Number: 4
Paragraph / Figure / Table / Note: 3. Definitions
Comment Type: Technical

Comment:

 

As a general matter, the proposed standards’ focus on whether energy is produced on-site or purchased is misplaced and could distort home ratings.  The goal of the standard should be  to encourage more efficient homes, and the source of the energy is not relevant to how efficiently it is used.    

A home that generates electricity on-site but does not use it efficiently should not be able to be rated at a lower, better Index value than a home that more efficiently uses purchased energy, but this is possible given the proposed definition of HERS Index. 

For example, a 2,000 square foot home that uses 500 million Btu of site energy and has on-site energy production of 500 million Btu will get a “perfect” score of 0, while a 2000 square foot home that is very efficient and only uses 20 million Btu of site energy will get a worse score, even though it is 25 times more energy efficient.  Such a result is contrary to the goal of the proposed standard.  Accordingly, “net purchased” should be stricken from before the word “energy” in the last line.

Proposed Change:

HERS Index

 …that uses zero net purchased energy...

 

Response:

Rejected. Removal of the word “net” from the definition would result in a definition that is counter to the intent. The word “net” is used because renewable energy produced from intermittent energy resources such as solar or wind power will not produce power at all of the times when energy is needed by the home. Thus, the term “net” is used to allow periods of excess power production to be weighed against a home’s energy use at times when the resource in unavailable. However, the comment also points out the fact that the period over which the energy use is to be accumulated is not specified. Therefore, the definition will be modified state “. . . that uses zero annual net purchased energy. . .” to specify that the period over which the energy use is to be considered is the annually.

If the commentator intended that both the word “net” and the word “purchased” were to be stricken as stated in the comment, then that would also not be acceptable because that would not allow a distinction between energy use that is produced on site by the home’s equipment and power that is purchased from an off-site production facility.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #24

Page Number: 3
Paragraph / Figure / Table / Note: 3. Definitions
Comment Type: Technical

Comment:

 The amount of electricity produced by site fossil fuel uses will be totally dependent on the type of generation technology used.  This definition is technically incorrect, as it assumes that an electric generation system in a home will have the exact same efficiency as central station generation.  For many types of generation systems, the will not be correct by orders of magnitude (e.g., the home generation is 20% efficient, and the central station generation is 60% efficient).

If RESNET does not choose to delete this definition and more appropriately focus the proposed standard and whether a home efficiency uses energy, regardless of that energy’s source, the approach to “Equivalent Electric Energy” must be modified to address technical concerns.  The amount of electricity produced by site fossil fuel uses will be totally dependent on the type of generation technology used.  The proposed approach incorrectly assumes that all possible home electric generation systems will have the same efficiency. RESNET should develop separate methodologies for determining the “Equivalent Electric Energy” from all possible forms of home electricity generation.  These methodologies must address the fact that many home generators do not separately meter their fuel use, which will significantly complicate the calculation of equivalent electric energy.

Moreover, using the proposed “Reference Electricity Production Efficiency” to generate an “Equivalent Electric Energy” value raises a series of other technical concerns.  First, it is not appropriate to assume that all home electricity generation systems produce electricity as efficiently as central station generation.  In general, because of economies of scale, central station generation will be more efficient by orders of magnitude.  Second, RESNET’s proposed “Reference Electricity Production Efficiency” value of 40 percent has not been sufficiently substantiated.  For example, it significantly underestimates the efficiency of modern natural gas-based generation, which has an efficiency of over 60 percent.  As noted, RESNET should develop separate methodologies specific to the various home generating systems for determining “Equivalent Electric Energy.”  If RESENT continues to use the proposed approach, it must better explain the basis for the proposed 40 percent value before finalizing this standard.  The use of incorrect estimates for electricity production efficiency will distort the HERS Index score. 

Proposed Change:

Delete the definition for "Equivalent Electric Energy". 

Equivalent Electric Energy - The amount of electricity that would be produced from site fossil fuel uses when converted to electric power using the Reference Electricity Production Efficiency.

 

 

Response:

Rejected. Site fossil fuel use must be converted to an electric equivalent before the two energy uses are comparable. Furthermore, for consistency, the conversion from one form of energy to the other should be uniform across all home energy ratings. The standards development committee has determined that the conversion efficiency of 40% proposed by BSR/RESNET Standard 301-201x is both equitable and balanced. In accordance with other another public comment (#49) the term “Reference Electricity Production Efficiency” will be deleted from BSR/RESNET Standard 301-201x and the conversion efficiency of 40% will be specified in Section 4.1.2 and 4.5.4 where the term is used in the draft.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #25

Page Number: 6
Paragraph / Figure / Table / Note: 3. Definitions
Comment Type: Technical

Comment:

There are many technical issues with this definition.  The first issue is that on-site power production does not make a home more energy efficient.  A 2,000 square foot home that uses 500 million Btu’s of site energy and has on-site energy production of 500 million Btu’s will get a “perfect” score of 0, while a 2000 square foot home that is very efficient and only uses 20 million Btu’s of site energy will get a worse score, even though it is 25 times more energy efficient. 

The second issue is that the proposed definition ignores on site thermal energy production, from such technologies as solar thermal energy systems and wood-fired stoves.  This proposed definition ignores on-site energy production from those sources, focusing only on electric production.  This does not make sense, especially for northern areas where heating energy is the dominant annual energy use of the home.

The third issue is the implicit assumption that on-site electric production efficiency will be exactly equal to the efficiency of central station power plants.  The amount of electricity produced by site fossil fuel uses will be totally dependent on the type of generation technology used.  For many types of generation systems, the will not be correct by orders of magnitude (e.g., the home generation is 20% efficient, and the central station generation is 60% efficient if it is combined cycle natural gas and 100% efficient if it is renewable).

The proposed approach incorrectly assumes that all possible home electric generation systems will have the same efficiency. RESNET should develop separate methodologies for determining the “Equivalent Electric Energy” from all possible home electricity generation.  These methodologies must address the fact that many home generators do not separately meter their fuel use, which will significantly complicate the calculation of equivalent electric energy.

Moreover, using the proposed “Reference Electricity Production Efficiency” to generate an “Equivalent Electric Energy” value raises a series of other technical concerns.  First, it is not appropriate to assume that all home electricity generation systems produce electricity as efficiently as central station generation.  In general, because of economies of scale, central station generation will be more efficient by orders of magnitude.  Second, RESNET’s proposed “Reference Electricity Production Efficiency” value of 40 percent has not been sufficiently substantiated.  This value significantly underestimates the efficiency of modern natural gas-based generation, which can have efficiencies of over 60 percent.  Further, it is not clear how and to what extent RESNET considered the efficiencies of purchased renewable generation or nuclear generation when coming up with this figure.  As noted, RESNET should develop separate methodologies specific to the various home generating systems for determining “Equivalent Electric Energy.”  If RESENT continues to use the proposed approach, it must better explain the basis for the proposed 40 percent value before finalizing this standard.  The use of incorrect estimates for electricity production efficiency will distort the HERS Index score. 

 

Proposed Change:

Delete the definition of "On-Site Power Production (OPP)".

On-Site Power Production (OPP) - Electric Power produced at the site of a Rated Home.  OPP shall be the net electrical power production, such that it equals the gross electrical power production minus any purchased fossil fuel energy, converted to its Equivalent Electric Power, used to produce the on-site power.

Response:

Rejected. BSR/RESNET Standard 301-201x will continue to credit electric energy produced on site as non-purchased energy. The commentator is incorrect about the standard not accounting for site thermal energy production from solar energy and wood-fired stoves and is also incorrect about the standard not accounting for the type of on-site generation technology used in the production of on-site energy. This factor is fully accounted in the specified calculation of PEfrac which references the determination of On-site power production as specified in Section 5.1.1.4 of BSR/RESNET Standard 301-201x.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #26

Page Number: 7
Paragraph / Figure / Table / Note: 3. Definitions
Comment Type: Technical

Comment:

Using the proposed “Reference Electricity Production Efficiency” to generate an “Equivalent Electric Energy” value raises a series of technical concerns.  First, it is not appropriate to assume that all home electricity generation systems produce electricity as efficiently as central station generation.  In general, because of economies of scale, central station generation will be more efficient by orders of magnitude.  Second, RESNET’s proposed “Reference Electricity Production Efficiency” value of 40 percent has not been sufficiently substantiated.  This value significantly underestimates the efficiency of modern natural gas-based generation, which can have efficiencies of over 60 percent.  Further, it is not clear how and to what extent RESNET considered the efficiencies of purchased renewable generation or nuclear generation when coming up with this figure.  As noted, RESNET should develop separate methodologies specific to the various home generating systems for determining “Equivalent Electric Energy.”  If RESENT continues to use the proposed approach, it must better explain the basis for the proposed 40 percent value before finalizing this standard.  The use of incorrect estimates for electricity production efficiency will distort the HERS Index score. 

EEI recommends that RESENT consider the following before moving forward with finalizing any “Reference Electricity Production Efficiency” factor:

First, the value for a “modern, high-efficiency, central power plant” of 40% is incorrect and understated.  The most common types of power plants built over the past 10-15 years have been combined cycle gas turbines or renewable plants (wind, solar, hydro, etc).  Renewable power plants, since no resources are lost, have an efficiency level of 100%, and even after transmission/ distribution losses, the overall efficiency is around 92.5%, not 40%.  The newest combined cycle gas turbines have efficiencies in the 59-61% range.  Even after considering national average transmission and distribution losses, the overall efficiency is at least 52-53% for these units.  See:

http://www.siemens.com/innovation/apps/pof_microsite/_pof-fall-2011/_html_en/combined-cycle-gas-turbines.html

The second issue is that on-site power production is usually much less efficient than central station power generation.  A gasoline generator operating at full load is about 19.3% efficient, and is about 15.3% efficient at 50% load.  See:

http://powerequipment.honda.com/generators/models/em4000

Other types of small scale electric generation (such as microturbines) have efficiency levels well below 40% (usually in the 26-31% range).  See:  http://www.capstoneturbine.com/_docs/Product%20Catalog_ENGLISH_LR.pdf

Therefore, the use of such an incorrect estimate will be to provide an overstated credit and distort the HERS score. 

Proposed Change:

Delete the definition of "Reference Electricity Production Efficiency"

Reference Electricity Production Efficiency - Electric power production efficiency, including all production and distribution losses, of 40%, approximating the efficiency of a modern, high-efficiency central power plant.  The Reference Electricity Production Efficiency is to be used only to convert site fossil fuel energy uses to an Equivalent Electric Power for the sole purposes of providing home energy rating system credit for On-site Power Production.

Response:

Rejected. The standards development committee has determined that the conversion efficiency of 40% proposed by BSR/RESNET Standard 301-201x is both equitable and balanced. In accordance with other another public comment (#49) the term “Reference Electricity Production Efficiency” will be deleted from BSR/RESNET Standard 301-201x and the conversion efficiency of 40% will be specified in Section 4.1.2 and 4.5.4 where the term is used in the draft.

BSR/RESNET Standard 301-201x will continue to credit electric energy produced on site as non-purchased energy. The commentator is incorrect about the standard not accounting for the type of on-site generation technology used in the production of on-site energy. This factor is fully accounted in the specified calculation of PEfrac which references the determination of On-site power production as specified in Section 5.1.1.4 of BSR/RESNET Standard 301-201x.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #27

Page Number: 9
Paragraph / Figure / Table / Note: 4.1
Comment Type: Technical

Comment:

As a general matter, the proposed standards’ focus on whether energy is produced on-site or purchased is misplaced and could distort home ratings.  The goal of the standard should be to encourage more efficient homes, and the source of the energy is not relevant to how efficiently it is used. 

A home that generates electricity on-site but does not use it efficiently should not be able to be rated at a lower, better Index value than a home that more efficiently uses purchased energy, but this is possible given the proposed definition of HERS Index. 

For example, a 2,000 square foot home that uses 500 million Btu of site energy and has on-site energy production of 500 million Btu will get a “perfect” score of 0, while a 2000 square foot home that is very efficient and only uses 20 million Btu of site energy will get a worse score, even though it is 25 times more energy efficient.  Such a result is contrary to the goal of the proposed standard. 

Proposed Change:

In Section 4.1, third line, change to:

value of 100 and a home that uses no net purchased energy has an Index value of 0 (zero).   

Response:

Rejected. BSR/RESNET Standard 301-201x will continue to credit electric energy produced on site as non-purchased energy. Whether the home achieves low ratings due to the use of on-site power production or the incorporation of greater efficiency technologies or some combination of both will be left to the marketplace to decide.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #28

Page Number: 10
Paragraph / Figure / Table / Note: Section 4.1.1
Comment Type: Technical

Comment:

Adding “fossil fuel” before “consumption” will make the standard more technically inclusive of all technologies and ensure that all energy usage is accounted for. 

Proposed Change:

In Section 4.1.1, for nEC_x and EC_r, replace “including auxiliary electric consumption” with “including auxiliary electric and fossil fuel consumption”. 

Response:

Rejected. The phrase “including auxiliary electric consumption” is purposefully intended to modify fossil fuel heating systems that require electric components for pilot or for heated air distribution. Modifying this language will only confuse the meaning.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #29

Page Number: 10
Paragraph / Figure / Table / Note: Section 4.1.1 Equations
Comment Type: Technical

Comment:

Based on the way that the equations are written, REUL and EC_r are cancelled out, since they will appear in the numerator and denominator when the nEC_x is substituted into the equation for nMEUL.   

Proposed Change:

The equations in Section 4.1.1 need to be revised to make algebraic sense.   

Response:

Rejected. The equations are purposefully step-wise in this procedure. The intent of the step-wise nature of this procedure is that the specified terms not be algebraically canceled out.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #30

Page Number: 11
Paragraph / Figure / Table / Note: 4.1.2
Comment Type: Technical

Comment:

As a general matter, the proposed standards’ focus on whether energy is produced on-site or purchased is misplaced and could distort home ratings.  The goal of the standard should be to encourage more efficient homes, and the source of the energy is not relevant to how efficiently it is used.    A home that generates electricity on-site but does not use it efficiently should not be able to be rated at a lower, better Index value than a home that more efficiently uses purchased energy, but this is possible given the proposed definition of HERS Index.

Consistent with this general objection, I would recommend that this equation be altered to remove the PEfrac, which will remove the on-site electricity production from the formula.  This will create a formula that is based solely on actual energy consumption and efficiency of the home.  The use of PEfrac will lead to less energy efficiency.  PEfrac is not technically correct since it only looks at on-site electricity production and ignores on-site thermal energy or other on-site energy production.

Proposed Change:

Change equation 4.1-2 to read as follows:

HERS Index =    PEfrac * (TnML / TRL) * 100

Response:

Rejected. BSR/RESNET Standard 301-201x will continue to credit electric energy produced on site as non-purchased energy. Whether the home achieves low ratings due to the use of on-site power production or the incorporation of greater efficiency technologies or some combination of both will be left to the marketplace to decide.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #31

Page Number: 11
Paragraph / Figure / Table / Note: Section 4.1.2
Comment Type: Technical

Comment:

As a general matter, the proposed standards’ focus on whether energy is produced on-site or purchased is misplaced and could distort home ratings.  The goal of the standard should be to encourage more efficient homes, and the source of the energy is not relevant to how efficiently it is used.    A home that generates electricity on-site but does not use it efficiently should not be able to be rated at a lower, better Index value than a home that more efficiently uses purchased energy, but this is possible given the proposed definition of HERS Index.

 

In another comment, it is recommended that PEfrac be removed from Equation 4.1-2 to create a formula that is based solely on the actual energy consumption and actual energy efficiency of the home being rated.  There are technical flaws with the use of a “reference electricity production efficiency” of 40%.   The most common types of power plants built over the past 10-15 years have been combined cycle gas turbines or renewable plants (wind, solar, hydro, etc).  Renewable power plants, since no resources are lost, have an efficiency level of 100%, and even after transmission/distribution losses, the overall efficiency is around 92.5%, not 40%.  The newest combined cycle gas turbines have efficiencies in the 59-61% range.  Even after considering national average transmission and distribution losses, the overall efficiency is at least 52-53% for these units.

In addition, there are technical flaws with the OPP that are addressed in another comment.  The largest flaw is that this equation does not consider the production of non-electric energy at the home.  By only looking at power and ignoring thermal energy or on-site fossil fuel energy (e.g., anaerobic digestors), the equation does not provide any “credit” to other forms of on-site energy production.  In addition, the equation ignores any upstream fossil fuel energy production losses.  Please see the following EIA article about natural gas production:  http://www.eia.gov/todayinenergy/detail.cfm?id=4030

Proposed Change:

Delete the definitions for PEfrac, TEU, and OPP from section 4.1.2.

Response:

Rejected. BSR/RESNET Standard 301-201x will continue to credit electric energy produced on site as non-purchased energy. Whether the home achieves low ratings due to the use of on-site power production or the incorporation of greater efficiency technologies or some combination of both will be left to the marketplace to decide. See also committee responses to Comments 23-30 from the same commentator.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #32

Page Number: 14
Paragraph / Figure / Table / Note: Table 4.2.2(1)
Comment Type: Technical

Comment:

Electric resistance systems (furnaces, boilers, zoned heaters) are used in many homes in the United States.  According to the Energy Information Administration 2009 Residential Energy Consumption Survey, of the 38.2 million US homes with electric space heating, about 50% (19.1 million) use central warm-air electric furnaces, and 9.8 million (25.7%) use heat pumps.  For the years 2000 through 2009, of the 6.9 million homes built with electric heat, 4.3 million used central warm-air furnaces and 2.2 million used heat pumps.  Therefore, the heating system row for electricity in this table should include electric furnaces, along with associated changes in Table 4.2.2(1a) that are shown in another comment.

Proposed Change:

In Table 4.2.2(1), under the Heating systems, for electric, change the text to “air source heat pump or furnace in accordance with Table 4.2.2(1a)”.

Response:

Rejected. BSR/RESNET Standard 301-201x will not reduce the efficiency of the HERS Reference Home below those Section 404 of the 2006 IECC for the Standard Reference Design.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #33

Page Number: 17
Paragraph / Figure / Table / Note: Table 4.2.2(1a)
Comment Type: Technical

Comment:

Electric resistance systems (furnaces, boilers, zoned heaters) are used in many homes in the United States and should be included in the “default” HERS reference home table.  According to the Energy Information Administration 2009 Residential Energy Consumption Survey, of the 38.2 million US homes with electric space heating, about 50% (19.1 million) use central warm-air electric furnaces, and 9.8 million (25.7%) use heat pumps.  For the years 2000 through 2009, of the 6.9 million homes built with electric heat, 4.3 million used central warm-air furnaces and 2.2 million used heat pumps.  Therefore, the reference home device for electricity in this table should include electric furnaces, along with associated changes in Table 4.2.2(1) that are shown in another comment.

Proposed Change:

In Table 4.2.2(1a), under the electric heating row, change the language in the “Reference Home Device” column to “7.7 HSPF air source heat pump or 99% AFUE  / 0.99 COP electric furnace or boiler”.

Response:

Rejected. BSR/RESNET Standard 301-201x will not reduce the efficiency of the HERS Reference Home below those Section 404 of the 2006 IECC for the Standard Reference Design.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #34

Page Number: 17
Paragraph / Figure / Table / Note: Table 4.2.2(1a)
Comment Type: Technical

Comment:

This will make the note consistent with proposed changes to Tables 4.2.2(1) and 4.2.2(1a). 

Electric resistance systems (furnaces, boilers, zoned heaters) are used in many homes in the United States and should be included in the “default” HERS reference home table.  According to the Energy Information Administration 2009 Residential Energy Consumption Survey, of the 38.2 million US homes with electric space heating, about 50% (19.1 million) use central warm-air electric furnaces, and 9.8 million (25.7%) use heat pumps.  For the years 2000 through 2009, of the 6.9 million homes built with electric heat, 4.3 million used central warm-air furnaces and 2.2 million used heat pumps. 

Proposed Change:

For Table 4.2.2(1a) note (i), change the last sentence to:

“For electric heating systems, the prevailing minimum efficiency air source heat pump furnace or boiler shall be selected”.

Response:

Rejected. BSR/RESNET Standard 301-201x will not reduce the efficiency of the HERS Reference Home below those Section 404 of the 2006 IECC for the Standard Reference Design.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #35

Page Number: 24
Paragraph / Figure / Table / Note: SEction 4.2.2.5.1.2
Comment Type: Technical

Comment:

There are miscellaneous gas appliances that are installed in homes that should be included into any analysis of the energy efficiency of a home under the proposed standard.  If all miscellaneous electric loads are included in calculations, then all miscellaneous gas or other fossil fuel loads should be included as well.

Based on published data and utility rate schedules, typical gas light systems use 18 therms per month, or 216 therms per year. 

Based on data from the American Gas Association Residential Natural Gas Market Survey of January 2010, the national average energy usage of a gas fireplace is 115 therms, with a range that varies by region from 48 to 283 therms per year.  

Proposed Change:

In Section 4.2.2.5.1.2, revise the wording to read “Where the Rated Home is equipped with natural gas cooking appliances or clothes drying appliances, or gas fireplaces or gas lighting systems,…..

In Table 4.2.2.5(2), add the following rows:

 

 

Gas Lights (therms)

216

 

 

Gas Fireplace (therms)

115

 

 

 

Response:

Rejected. The values provided by Table 4.2.2.5(2) are specified to replace the values given in Table 4.2.2.5(1) for all electric homes. There is no electrical reference equivalent to a gas fireplace and there is virtually no use of gas-fired lighting systems in homes.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #36

Page Number: 43
Paragraph / Figure / Table / Note: Section 4.5.4.1
Comment Type: Technical

Comment:

The proposed changes will make the equation technically correct.  The use of a “reference electric production efficiency” creates a total distortion of the energy usage and energy efficiency of homes, by discounting the fossil fuel energy usage by 60%.   

As a simplified example, if a fossil fuel appliance uses 341,200 Btu’s per year, the actual equivalence is 341,200 / 3412 = 100 kWh.  However, under the current equation, the value used for the HERS score would be a vastly understated and incorrect 40 kWh “equivalent”.  The more energy an appliance or system uses, the larger the distortion of the score will be.

There are technical flaws with the use of a “reference electricity production efficiency” of 40%.   The most common types of power plants built over the past 10-15 years have been combined cycle gas turbines or renewable plants (wind, solar, hydro, etc).  Renewable power plants, since no resources are lost, have an efficiency level of 100%, and even after transmission/distribution losses, the overall efficiency is around 92.5%, not 40%.  The newest combined cycle gas turbines have efficiencies in the 59-61% range.  Even after considering national average transmission and distribution losses, the overall efficiency is at least 52-53% for these units.

Using the proposed “Reference Electricity Production Efficiency” to generate an “Equivalent Electric Energy” value raises a series of technical concerns.  First, it is not appropriate to assume that all home electricity generation systems produce electricity as efficiently as central station generation.  In general, because of economies of scale, central station generation will be more efficient by orders of magnitude.  Second, RESNET’s proposed “Reference Electricity Production Efficiency” value of 40 percent has not been sufficiently substantiated.  This value significantly underestimates the efficiency of modern natural gas-based generation, which can have efficiencies of over 60 percent.  Further, it is not clear how and to what extent RESNET considered the efficiencies of purchased renewable generation or nuclear generation when coming up with this figure.  As noted, RESNET should develop separate methodologies specific to the various home generating systems for determining “Equivalent Electric Energy.”  If RESENT continues to use the proposed approach, it must better explain the basis for the proposed 40 percent value before finalizing this standard.   

In addition, the equation also is technically incorrect and inconsistent in that it does not account for the energy losses associated with fossil fuel energy production.  Please see the following EIA article about natural gas production:  http://www.eia.gov/todayinenergy/detail.cfm?id=4030

 

Proposed Change:

Revise Section 4.5.4.1 to read as follows:

4.5.4.1.  Energy units used in the calculation of energy savings shall be units of Equivalent Electric Energy using the Reference Electricity Production Efficiency for fossil fuels.  Equivalent electric energy use shall be calculated using Equation 4.5-1.

kWheq  =  kWhelec  +  Btufossil * 0.40 / 3412

Response:

Rejected. BSR/RESNET Standard 301-201x will continue to represent fossil fuel use as an equivalent electric energy where it is necessary that all fuel uses be compared. See also committee responses to comments #23 - #31 from the same commentator.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #37

Page Number: 47
Paragraph / Figure / Table / Note: Section 5.1.1.4
Comment Type: Technical

Comment:

As a general matter, the proposed standards’ focus on whether energy is produced on-site or purchased is misplaced and could distort home ratings.  The goal of the standard should be to encourage more efficient homes, and the source of the energy is not relevant to how efficiently it is used.    A home that generates electricity on-site but does not use it efficiently should not be able to be rated at a lower, better Index value than a home that more efficiently uses purchased energy, but this is possible given the proposed definition of HERS Index. 

For home energy efficiency ratings, on-site power production or, to be more technically accurate, on-site energy production, should not be used in any formula.  On-site energy production does not make a home more energy efficient.

The example shown in Section 5.1.1.4 highlights the problem.  The most common types of gas-fired power plants built over the past 15 years have been combined cycle gas turbines.  The newest combined cycle gas turbines have efficiencies in the 59-61 percent range.  Even after considering national average transmission and distribution losses, the overall efficiency is at least 52-53 percent for these units – well above the value of 0.40 shown throughout the proposed standard. 

A more accurate value of electric production would result in the example creating the following estimate:

OPP  =   3.413 MBtu – (6 MBtu * 0.60) = -0.187 MBtu

 Also, this equation will be inadequate in areas where central station generation is dominated by renewable energy (e.g., hydroelectric and wind in the Pacific Northwest).

Proposed Change:

Delete Section 5.1.1.4.

5.1.1.4  If the Rated Home....

For example, assume....

 

Response:

Rejected. BSR/RESNET Standard 301-201x will continue to use 40% delivered efficiency for the conversion of fossil fuels to their electric equivalent. See also committee responses to comments 23-31 from the same commentator.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #38

Page Number: as listed
Comment Type: General

Comment:

A certfied HERS score must include duct testing and infiltration testing via blower door & duct tester. The 2012 codes require such testing and an accurate HERS score should require it.

For projected ratings the code or program maximum allowable number should be used. (i.e. 2009 IECC or unlisted code should be at 7 ACH) 

Response:

Accepted. BSR/RESNET Standard 301-201X will be modified to require testing of envelope leakage and air distribution system leakage for Confirmed Ratings. The definition of a confirmed rating will be revised as follows.


Confirmed Rating – A Rating Type accomplished using the actual data gathered from an on-site audit inspection and, if required, performance testing of the physical building and its installed systems and equipment including, at a minimum, air distributions system testing and envelope leakage testing.

Comment #39

Page Number: 49
Paragraph / Figure / Table / Note: Section 5.1.2.2.1.1 & Table 5.1.2(1)
Comment Type: Technical

Comment:

The current text is not technically consistent.  For fossil fuel emissions, information is provided about emissions at the house, but there is no information about associated upstream emissions.  For electricity, no information is provided about the fact that using electrical appliances in the home generates zero emissions at the home, but there is a reference to associated upstream emissions.

Any upstream emissions associated with electricity production are not relevant to any assessment as to how energy efficiency a home is, particularly when home owners have little option to control or reduce these emissions.  Accordingly, it does not make sense to “link” household electric usage with power plant emissions.  Moreover, the proposed standard takes an inconsistent approach as to how to deal with upstream emissions related to different fuels.

Since this standard is about rating homes, not energy supply, any information about emissions should be focused on the emissions produced by equipment in the home, at the home, or at the home site.  The proposed edits create a consistent comparison methodology.

Also, federal laws have capped or reduced electric generation NOx and SO2 emissions significantly over the past 22 years (see http://www.eia.gov/electricity/annual/html/table3.9.cfm), so it does not make sense to “link” household electric usage with capped power plant emissions.  

Proposed Change:

For Section 5.1.2.2.1.1, revise the text to read “For electricity use, pollution emissions using the statewide average emission rates provided by the Environmental Protection Agency’s most recent eGrid database16 for electricity generation. shall be calculated using the emission factors given in Table 5.1.2(1) below.

Also, modify Table 5.1.2(1) as follows:

 

 

 

Fuel Type

 

Units

MBtu

per Unit

CO2

lb/MBtu

NOx

lb/MBtu

SO2

lb/MBtu

Electricity

(rest of the table is unchanged)

 

kWh

0.003413

0.0000

0.0000

0.0000

 

Response:

Rejected. The assertion that electric energy consumption results in zero environmental pollution emissions is rejected.


You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #40

Page Number: 73
Paragraph / Figure / Table / Note: Annex B Table 3.2(1)(a)
Comment Type: Technical

Comment:

Electric resistance systems (furnaces, boilers, zoned heaters) are used in many homes in the United States and should be included in the “default” HERS reference home table.  According to the Energy Information Administration 2009 Residential Energy Consumption Survey, of the 38.2 million US homes with electric space heating, about 50% (19.1 million) use central warm-air electric furnaces, and 9.8 million (25.7%) use heat pumps.  For the years 2000 through 2009, of the 6.9 million homes built with electric heat, 4.3 million used central warm-air furnaces and 2.2 million used heat pumps.  Therefore, the reference home device for electricity in this table should include electric furnaces, along with associated changes in Table 4.2.2(1) that are shown in another comment.

Proposed Change:

On Page 73, in Table 3.2(1)(a), under the electric heating row, change the language in the “Reference Home Device” column toread as follows:  “7.7 HSPF air source heat pump or 99% AFUE  / 0.99 COP electric furnace or boiler”.

Response:

Rejected. The Annexes associated with software verification testing and accreditation will be removed from BSR/RESNET Standard 301-201x.
You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #41

Page Number: 73
Paragraph / Figure / Table / Note: Annex B Table 3.2(1)(a) note i
Comment Type: Technical

Comment:

This will make the note consistent with proposed changes to Tables 4.2.2(1) and 4.2.2(1a). 

Electric resistance systems (furnaces, boilers, zoned heaters) are used in many homes in the United States and should be included in the “default” HERS reference home table.  According to the Energy Information Administration 2009 Residential Energy Consumption Survey, of the 38.2 million US homes with electric space heating, about 50% (19.1 million) use central warm-air electric furnaces, and 9.8 million (25.7%) use heat pumps.  For the years 2000 through 2009, of the 6.9 million homes built with electric heat, 4.3 million used central warm-air furnaces and 2.2 million used heat pumps. 

Proposed Change:

For Table 3.2(1)(a) note (i), change the last sentence to “For electric heating systems, the prevailing minimum efficiency air source heat pump furnace or boiler shall be selected”.

Response:

Rejected. The Annexes associated with software verification testing and accreditation will be removed from BSR/RESNET Standard 301-201x.


You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #42

Page Number: 13
Paragraph / Figure / Table / Note: Table 4.2.2(1)
Comment Type: General

Comment:

The standard refers to "mechanical ventilation" multiple times, when a more appropriate reference would be "whole-house mechanical ventilation" (WHMV).  By replacing references to "mechanical ventilation" with "whole-house mechanical ventilation" and inserting a new definition for "whole-house mechanical ventilation", PDS-301 will be consistent with the lexicon of ASHRAE 62.2 and the 2012 IRC and IECC.  The definition proposed below is copied from the 2012 IRC and IECC. 

Further, to ensure consistency with ASHRAE 62.2, please formally rescind RESNET Formal Interpretation 2007-001, which provides an incorrect interpretation of ASHRAE 62.2 (i.e., the interpretation states that occupant override controls are not permitted, while ASHRAE 62.2 specifically requires that they be provided).  This incorrect interpretation is currently causing problems for raters and manufacturers who are trying to comply with RESNET standards and ASHRAE 62.2.     

Thanks for your consideration.

Proposed Change:

1. Section 3 - Insert a new definition as follows:  

Whole-house mechanical ventilation system – An exhaust system, supply system, or combination thereof that is designed to mechanically exchange indoor air with outdoor air when operating continuously or through a programmed intermittent schedule to satisfy a whole house ventilation rate.

2. Replace "mechanical ventilation" with "whole-house mechanical ventilation” at the following locations:

a. Table 4.2.2(1), page 13, 3rd column:  

For residences without whole-house mechanical ventilation systems that are tested in accordance with ASHRAE Standard 119, Section 5.1, the measured air exchange rate (e) but not less than 0.30 ach

For residences with whole-house mechanical ventilation systems that are tested in accordance...

b. Table 4.2.2(1), page 13, 1st column: Whole-house mechanical ventilation:

c. Table 4.2.2(1), page 13/14, 2nd column: None, except where a whole-house mechanical ventilation system is specified by the Rated Home...

d. Page 16: (f) The combined air exchange rate for infiltration and whole-house mechanical ventilation shall be determined in accordance with equation 43 of 2001 ASHRAE Handbook of Fundamentals page 26.24 in combination with the" Whole-house Ventilation" provisions of 2001 ASHRAE Handbook of Fundamentals, page 26.19 for intermittent whole-house mechanical ventilation.

e. Page 24: 4.2.2.5.1.4. Whole-House Mechanical Ventilation. Where whole-house mechanical ventilation is provided in the Rated home...

f. Page 31: 4.2.2.5.2.12. Whole-House Mechanical Ventilation System Fans. If whole-house mechanical ventilation fans are present in the Rated Home...

g. Page 32: 4.3.3.1.4. Whole-house Mmechanical ventilation rate shall be zero.

h. Page 37, Table 4.4.2(1): 20. Whole-House Mechanical Ventilation System(s)

i. Page 61: 16. Whole-house Mmechanical ventilation kWh/yr, if appropriate

j. Page 70, Table Table 3.2(1), column 3: …For residences without whole-house mechanical ventilation systems that are tested in accordance with ASHRAE Standard 119, Section 5.1, the measured air exchange rate (e) but not less than 0.35 ach

For residences with whole-house mechanical ventilation systems that are tested in accordance with ASHRAE Standard 119, Section 5.1, the measured air exchange rate(e) combined with the whole-house mechanical ventilation rate…

k. Page 70, Table 3.2(1), column 1: Whole-House Mechanical Ventilation:

l. Page 70, Table 3.2(1), column 2: None, except where a whole-house mechanical ventilation system is specified by the Qualifying Home, in which case…

m. Page 73: (f) The combined air exchange rate for infiltration and whole-house mechanical ventilation shall be determined in accordance with equation 43 of 2001 ASHRAE Handbook of Fundamentals page 26.24 in combination with the” Whole-house Ventilation” provisions of 2001 ASHRAE Handbook of Fundamentals, page 26.19 for intermittent whole-house mechanical ventilation.

n. Page 77: 15. Whole-house Mmechanical ventilation kWh/yr, if appropriate

o. Page 80: 15. Whole-house Mmechanical ventilation kWh/yr, if appropriate

3. Update the reference for equations from ASHRAE Fundamentals to cite the relevant equations in the 2009 edition (instead of the 2001 edition, which is outdated): d. Page 16: (f)

4. Provide further clarification for how to account for WHMV flow rates in equipment sizing:

Page 33: 4.3.3.2.4. Where a whole-house mechanical ventilation system is provided, the whole-house Mmechanical ventilation flow rate shall only be included for systems that are controlled to run every hour or every time the HVAC system operates. Standard Flow rates for bathroom, and kitchen, and other local exhaust ventilation that does not serve as a component of a whole-house mechanical ventilation system may shall not be considered as ventilation for sizing purposes.

Response:

Accepted. Proposed changes will be made to the draft.

Comment #43

Page Number: 22
Paragraph / Figure / Table / Note: Section 4.2.2.2.6
Comment Type: Technical

Comment:

 The Zone Method is not an accurate calculation procedure for cold-formed steel framing (C-sections).  It significantly overestimates the U-factor of steel assemblies.  Further, The ASHRAE Handbook of Fundamentals (Chapter 27) describes multiple methods for calculating thermal properties of assemblies containing steel framing.  There is no one method that is appropriate across the board for all steel assemblies.  Each has deficiencies or limitations. 

The Handbook of Fundamentals clearly cites research by Oak Ridge National Laboratory that shows the modified zone method to be the most accurate method for steel framing.  However, that method is limited as well, since it assumes a clear-wall assembly without framing for openings.  It may not be applicable to assemblies with higher framing factors.

The methods most appropriate for conventional assemblies using cold-formed steel (that are not clear wall assemblies) are either based on hot box tests or the series path method described in ASHRAE 90.2. 

The 90.2 method includes typical series path equations with a correction factor based on member depth and spacing.  The method is the same one used to develop steel framing U-factors in Appendix A of ASHRAE 90.1 for other than low-rise residential buildings.  Thus, two ANSI consensus committees have accepted this method.  Further, the same method and correction factors were included in the 2003 International Energy Conservation Code (IECC).  However, over time the format of the IECC changed such that the focus was towards the simple prescriptive table approach, and thus most of the conversion equations, including cold-formed steel framing, were summarily removed in favor of pre-calculated tables.

Hot box test results are the most accurate of the methods but very expensive to conduct.  Thus, we recognize the need and support the use of rational and appropriate calculation methods.  Further, it is appropriate to modify hot box test results when an assembly is different than the tested assembly if the base assembly (i.e., studs and cavity insulation) are identical.  Corrections based on different levels of continuous insulation, siding or other components outside of the cavity are appropriate and recognized by our modification.

Given the very conservative nature of the zone method and its limitations in regard to cold-formed (or light gauge) steel, we recommend that it be removed as the lone method for steel assemblies and replaced with the three more appropriate options shown in our modification to proposed Section 4.2.2.2.6.

Proposed Change:

 

Modify Section 4.2.2.2.6 as follows:

4.2.2.2.6. Steel framing in insulated assemblies: calculations for the overall thermal properties of steel-framed walls, ceilings and floors shall be based on the “Zone Method” from 2009 ASHRAE Handbook of Fundamentals (p 27.5); or equivalent. one of the following methods:

  1. A series path calculation described in Section 5.5 of ANSI/ASHRAE Standard 90.2-2007 (Energy Efficient Design of Low Rise Buildings). 
  2. Testing in accordance with ASTM C1363 (Standard Test Method for Thermal Performance of Building Materials and Envelope Assemblies by Means of a Hot Box Apparatus).  Test results may be modified to add or subtract R-values to the tested assembly to reflect differences between the tested assembly and proposed assemblies when such differences occur outside of the cavity.
  3. For clear wall assemblies (without door or window headers and jack or king studs), the modified zone method from 2009 ASHRAE Handbook of Fundamentals, Chapter 27.
Response:

Accepted. The proposal change will be incorporated in the final Committee draft of BSR/RESNET Standard 301-201x.

Comment #44

Page Number: 1
Paragraph / Figure / Table / Note: FORWARD
Comment Type: Editorial

Comment:

 

Clarification and increased probability that the standard will be adopted and can be applied and used if adopted

Proposed Change:

There are numerous places in the standard that use different terms, statements, formats for presentation of the same thing; these should be made consistent throughout the document.  This is a general comment and placed here under the Forward on page 1 as it applies to multiple sections in the standard.

Response:

Rejected. The comment is non-specific and does not propose specific changes to the language in BSR/RESNET Standard 301-2010x. The comment will be considered in future maintenance of the Standard.
You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #45

Page Number: 1
Paragraph / Figure / Table / Note: FORWARD
Comment Type: Editorial

Comment:

 

IP is certainly the most useful way to present the requirements, but for ANSI and adoptability purposes SI are also now recognized in standards criteria,

Proposed Change:

 

The standard is presented entirely in IP units.  SI units should be added in parentheses.

Response:

Rejected. An effort will be made to provide SI units in future revisions of BSR/RESNET Standard 301-201x.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #46

Page Number: 1
Paragraph / Figure / Table / Note: section 1
Comment Type: Editorial

Comment:

 

To improve the text to more accurately reflect a purpose statement.  There is no reason to refer to intent as that occurs by virtue of the rating and labeling standards being developed and published.  It is also not necessary to include a permissive statement about providers of HERs following the document.  The suggested changes result in a more concise and accurate statement of purpose that leaves it open as to who uses the document and more accurately presents the purpose of the standard as promoting more uniform and consistent rating and labeling of residential buildings.

Proposed Change:

 

1. Purpose. The provisions of this document are intended to establish national residential energy rating and labeling Standards, consistent with the provisions of the Energy Policy Act of 1992, which any provider of home energy ratings may follow to provide for produce uniform energy ratings and energy performance labels for residential buildings uniformity and consistency in the rating and labeling of such buildings.

Response:

Accepted. The proposed revisions will be incorporated in the final committee draft of BSR/RESNET Standard 301-201x.

Comment #47

Page Number: 1
Paragraph / Figure / Table / Note: section 2
Comment Type: Editorial

Comment:

 

The last sentence is not appropriate for a standard with the stated purpose and intended use given in Section 1 (Purpose).  It is informational in nature at the very least and should be included in any informative appendices deemed appropriate to illuminate the content of the standard but not intended to be part of the standard.  Where there are one or more specific criteria in this standard that relate to or would specifically refer to the referenced document then it is appropriate to include such a reference where relevant within this standard.  It is not an appropriate statement for the scope of a standard; scope simply stating what the standard covers (and by absence in the scope what it does not cover).  The scope should clearly outline to what the standard applies and when done appropriately it should not need clarification via exceptions.  More appropriate language consistent with other standards and model codes is proposed to more clearly define the scope, most notably clarification of residential buildings.  It is noted the term residential building is not defined in the standard yet the term is used in the standard.  Consideration might be given to simply saying in the scope “low-rise residential buildings” and then define that term as suggested in this comment in the definitions section of the standard .  The term “dwelling unit” is generally understood and is specifically defined in model codes and standards to distinguish multi-family buildings from hotels and motels and other residential use group buildings.

 

Proposed Change:

 

2. Scope. This standard is applicable to all one and two family dwellings and residential buildings not over three stories in height above grade containing multiple dwelling units. single family residences and to all multifamily residences three stories or less in height above ground excepting hotels and motels. This Standard is a companion to the RESNET Mortgage Industry National Home Energy Rating Systems Standards.

 

Response:

Accepted as modified. The proposed revisions as modified below will be incorporated in the final committee draft of BSR/RESNET Standard 301-201x.

“2. Scope. This standard is applicable to all one- and two-family dwellings and dwelling units in residential buildings not over three stories in height above grade containing multiple dwelling units.”

Comment #48

Page Number: 1
Paragraph / Figure / Table / Note: section 3
Comment Type: General

Comment:

The current introductory text in Section 3 can be enhanced as suggested and would then be consistent with that in other standards and model codes.  It is suggested that Section 3 be separated into three subsections (general, definitions and acronyms).  The first as proposed above more clearly states the general guidance associated with definitions.  The second becomes the current terms that are defined and the third becomes acronyms.  The current definitions and acronyms are better separated to enhance use of the standard, noting that the delineation of an acronym is not technically a definition.  Many standards development organizations format their standards to separate definitions from acronyms.  This makes it easier to use the standard and most importantly ensures that terms that have an actual definition are all grouped together and not separated by acronyms.

Proposed Change:

.1 General.  Unless stated otherwise, the terms and words in Section 3.2 shall have the meanings indicated therein.  Words used in the present tense include the future, words in the masculine gender include the feminine and neuter, and singular and pleural are interchangeable.  Terms not defined in Section 3.2 shall have ordinary accepted meanings such as the context implies.

 

3.2 Specific Words and Terms.

(Simply list out in alphabetical order all terms and words defined in the current draft).

3.3 Acronyms

(Simply list out in alphabetical order all acronyms that are not associated with a definition).

Response:

Accepted. The proposed revisions will be incorporated in the final committee draft of BSR/RESNET Standard 301-201x.

Comment #49

Page Number: 7
Paragraph / Figure / Table / Note: section 3
Comment Type: General

Comment:

 

The definition of “Reference Electricity Production Efficiency” contains requirements.  The purpose of a definition is to define a term.  The appropriate place to include requirements that relate to the term defined is at the point in the standard where the term is used. 

Response:

Accepted. The definition and all references to the term “Reference Electricity Production Efficiency” will be struck and the requirements specified by the definition will be moved to Sections 4.1.2 and 4.5.4 of BSR/RESNET Standard 301-201x.

Comment #50

Page Number: 9
Paragraph / Figure / Table / Note: section 3
Comment Type: Technical

Comment:

 

Revise the definition of U-factor to be consistent with that used in ASHRAE standards and ICC model codes so as to eliminate confusion amongst the building community that would use the RESNET standard.

Response:

Accepted. These definition of R-Value and U-Factor will be harmonized across these standards and included in the final Committee draft of BSR/RESNET Standard 301-201x, as follows.

“R-value – The inverse of the time rate of heat flow through a body from one of its bounding surfaces to the other surface for a unit temperature difference between the two surfaces, under steady state conditions, per unit area (h·ft2·oF/Btu) [m2·K/W].

U-Factor – The coefficient of heat transmission (air to air) through a building component or assembly, equal to the time rate of heat flow per unit area and unit temperature difference between the warm side and cold side air films (Btu/h·ft2·oF) [W/m2·K].”

Comment #51

Page Number: 9
Paragraph / Figure / Table / Note: section 4.1
Comment Type: Editorial

Comment:

 

The language in Section 4.1 appears unnecessary and its elimination should help to simplify the standard (e.g. fewer and more precise wording in a standard will enhance its acceptability and can lead to fewer interpretive issues and increase uniformity of use.  The term “HERS Index” is defined in Section 3 and there is no reason to repeat that definition in Section 4.1.  This can lead to confusion and needlessly complicates the standard.  More importantly, should this standard be adopted and then amended the location of these criteria here and in the definitions section increases the chance in amending the document that one set of these criteria might not be appropriately amended.  The sentence associated with states or territories having an alternative method should not be addressed in a standard that is intended for national use.  If the standard is written correctly it should have a high rate of adoption and use and need not address what might happen if there are alternative methods.  Let those who want to divert from the standard do so with good reason on their own. Recognizing such situations in this standard would seem to weaken the intent of RESNET in developing and publishing this standard and as such encourage such alternatives.    A section on determining a HERS index should do just that – tell how to make the determination and as amended pursuant to this comment we believe this is just what the standard will do; relying as needed on the definitions in Section 3.

 

Proposed Change:

 

4.1. Determining the HERS Index. The HERS Index for a residential building shall be a numerical integer value that is based on a linear scale constructed such that the HERS Reference Home has an Index value of 100 and a home that uses no net purchased energy has an Index value of 0 (zero). Each integer value on the scale shall represent a 1% change in the total energy use of the Rated Home relative to the total energy use of the Reference home.  Except in states or territories whose laws or regulations require a specific alternative method, which shall control, equations 4.1-1 and 4.1-2 shall be used in a 2 step process to calculate the HERS Index for the Rated Home, as follows: determined in accordance with Sections 4.1.1 and 4.1.2.

 

Response:

Accepted. The proposed revisions will be incorporated in the final committee draft of BSR/RESNET Standard 301-201x.

Comment #52

Page Number: 9
Paragraph / Figure / Table / Note: section 4.1.1
Comment Type: Editorial

Comment:

 

The proposed text can be improved with respect to its presentation in standards language.  The use of the term individual is moot due to the use of the word each as proposed.  Also clarification is needed that the loads are space heating, space cooling and domestic hot water.  This change is intended to and we believe will clarify intent and simplify the presentation and use of the standard.  It is noted that an acronym appears in this section yet is not proposed for Section 3.  If this acronym is retained it may be a candidate for listing in a section proposed for only acronyms (see comments to Section 3 suggesting separate subsections for definitions and acronyms).  In addition it does not appear clear if the term “normalized modified energy use loads” can be fully understood and applied by all users of the standard and as such this term should be defined.  On a general note the format and manner in which equations are presented in the standard should be checked for consistency throughout.

Proposed Change:

 

4.1.1. Calculating End Use Loads.  Calculate the The individual normalized Modified End Use Loads (nMEUL) for space heating and , cooling, and domestic hot water use shall each be determined in accordance with using equation 4.1-1:

Response:

Accepted. The proposed revisions will be incorporated in the final committee draft of BSR/RESNET Standard 301-201x.

Comment #53

Page Number: 10
Paragraph / Figure / Table / Note: equation 4.1-1
Comment Type: General

Comment:

 

The use of the term “accredited simulation tools” is used with respect to simulation tools.  The terms accredited or “accredited simulation tools” are not defined but the following terms are:

Accreditation Categories (software tools) – Specific computer software tool functionalities that may be accredited by RESNET under the provisions of this Standard.

Accredited Software Rating Tool – A computerized procedure that is accredited by RESNET for the purpose of conducting home energy ratings and calculating the annual energy consumption, annual energy costs and a HERS Index for a home.

The manner in which the above definitions are presented and the use of the term “accredited simulation tools” in Equation 4.1-1 suggests that it is the intent of this standard is to provide for the title, purpose and scope as established for the standard as well as institute a situation where those adopting the standard must then defer to and rely on RESNET accreditation on an ongoing basis; a process that is likely to change over time and over which they have no oversight.  The manner in which  RESNET is engaged or required to be involved as an accrediting entity with respect to use of the standard  (e.g. conformity assessment) should be decoupled from the provisions in the standard related to how a rating is determined and presented. 

The manner in which the issue of conformity assessment is addressed in the standard can pose a problem if RESNET intends to have this standard adopted in any way by Federal, state or local authorities as part of their building-related legislation or regulation directly or as an alternative path to compliance with building energy codes.  The issue of conformity assessment is addressed through the use of terms such as “approved” and “nationally recognized” in model codes and standards. Then as warranted federal, state or local agencies that formulate, adopt and implement associated laws and regulations will determine, based on those terms as defined in the model codes and standards, the degree to which they would verify the continued acceptance of any third parties.  Based on that ongoing assessment they would continue (or not) to allow them to conduct testing, certification, etc. work associated with conformity assessment on behalf of the federal, state or local officials who have that ultimate responsibility as the adopting entity.  Inclusion of RESNET in this standard as an accrediting body with respect to conformity assessment with the standard should be seriously considered and removed in place of the suggested use of “approved” and its definition.  As currently presented in the standard RESNET accreditation is listed as the only acceptable conformity assessment method as a first-party entity (e.g. self-certification and accreditation) with respect to its ability to perform the stated services on a continuing (e.g. in perpetuity) basis.  This is something that accrediting entities such as ANSI, NAVLAP, IAS and others are actively engaged in on an ongoing basis as third party accrediting entities. As such they could assess any RESNET certification programs separately and through certification RESNET could be recognized as an “approved” entity.  Inclusion of a first party conformity assessment entity or accrediting agency as RESNET is in the standard opens up the question for users – who then provides oversight of those agencies ongoing activities to ensure they meet standards for conformity assessment entities and should continue to be “approved”.   

The issue of who or want is “approved” needs to be addressed in a generic way through the use of the term “approved” and a definition of that term meaning the authority who has adopted and is requiring use of this standard.  Certainly RESNET programs associated with accrediting can be considered in looking at who is “approved” and there is no reason why they would not be subsequently approved. Requiring accreditation by RESNET specifically and singularly by name in the standard could adversely affect the adoption and use of the standard.  For this reason it is recommended that RESNET eliminate a reference to RESNET accreditation and replace that term with “approved” and a definition of approved consistent with that in model codes and standards.   Then separately such RESENT accreditation programs assessed by a recognized third party accrediting agency who can document on continuing basis the acceptability of RESNET accreditation in meeting any criterion that requires third party approval.   We believe by doing this the RESNET standard can secure the acceptability that RESNET desires. If not certainly some will adopt the standard and resultant programs but later on challenges to the acceptability of a singular self-certified entity could adversely affect the continued reliance on the standard.

 

Proposed Change:

Replace the term “accredited” with “approved” and add a definition of approved as “Approved by the entity adopting this standard as a result of investigation and tests conducted by him or her, or by reason of accepted principles or tests by nationally recognized organizations.”on 4.1-1:

Response:

Accepted. The provisions on Software Verification and Testing will be removed from the proposed BSR/RESNET Standard 301-201x to another document promulgated by RESNET. The terms “Accreditation Categories” and “Accredited Software Rating Tool” will be stricken from the definitions. References to “accreditation” of products by RESNET will be removed from BSR/RESNET Standard 301-201x and replaced with “approved” where Approved is defined as follows:

Approved – shall mean approved by an entity adopting and requiring the use of this Standard as a result of investigation and tests conducted by the entity or by reason of accepted principles or tests by nationally recognized organizations.”

Comment #54

Page Number: 10
Paragraph / Figure / Table / Note: section 4.1.2
Comment Type: Editorial

Comment:

 

The proposed text can be improved with respect to how it is presented in standards language.  It is preferable to state the subject first and then the requirement.

Proposed Change:

 

4.1.2. Calculating the HERS Index.  Determine the The HERS Index using shall be determined in accordance with equation 4.1-2:

Response:

Accepted. The proposed revisions will be incorporated in the final committee draft of BSR/RESNET Standard 301-201x.

Comment #55

Page Number: 11
Paragraph / Figure / Table / Note: section 4.2
Comment Type: Editorial

Comment:

 

The two separate subsections (4.2.1 and 4.2.2) appear confusing and could be stated more clearly.  We believe the proposed change does this by simply indicating to use identical analytical approaches and configure the homes in accordance with the stated table. 

Proposed Change:

 

4.2.1. General Requirements.  Except as specified by this Section, the HERS Reference Home and the Rated Home shall be configured and analyzed using identical methods and techniques.

4.2.2. Residence Specifications.  The HERS Reference Home and Rated Home shall be configured and analyzed using identical analytical approaches and configured as specified by Table 4.2.2(1).

Response:

Rejected. The proposed revisions do not improve the meaning or clarity of Section 4.2 of BSR/RESNET Standard 301-201x.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #56

Page Number: 15
Paragraph / Figure / Table / Note: section 4.2.1(1)
Comment Type: Editorial

Comment:

 

Clarification and accuracy. 

Proposed Change:

 

The table in the thermostat row references nonexistent Section 4.2.1.1. Reference should be made to the correct section.

Response:

Accepted. The correct reference for programmable thermostats is Section 4.3.1 and this revisions will be incorporated in the final committee draft of BSR/RESNET Standard 301-201x.

Comment #57

Page Number: 15
Paragraph / Figure / Table / Note: table 4.2.1(1) note (a)
Comment Type: General

Comment:

 

If the term glazing area or door area are used more than one place in the standard it may be advisable to include a definition of glazing and doors in Section 3, thereby eliminating the need to define the term where used throughout the standard.  Moreover the existence of a definition ensures uniform and consistent application and use of the standard with respect to the defined terms that can be compromised if the terms are defined/redefined each time they appear in the standard.  In addition if those terms are used somewhere in the standard and not defined it is unclear without a definition how they would be defined.

Proposed Change:

 

Note (a) seems more appropriate as a definition. 

Response:

Accepted. Definition for glazing area and door area as used in Table 4.2.1(1), note (a) will be incorporated in Section 3 of the final committee draft of BSR/RESNET Standard 301-201x.

Comment #58

Page Number: 16
Paragraph / Figure / Table / Note: table 4.2.1(1) note (b)
Comment Type: Editorial

Comment:

 

See prior comment to Section 2 concerning the scope of the standard and the necessity to accurately define residential buildings within the scope of the standard consistent with terminology used in building construction regulations.  The proposed change above captures the intent of the draft standard 

Proposed Change:

 

(b) For homes with one- and two-family dwellings with conditioned basements and for multi-family attached homes residential buildings not over three stories in height above grade containing multiple dwelling units the following formula shall be used to determine total window area:

Response:

Accepted as modified. The proposed changes as modified below will be included in the final Committee draft of BSR/RESNET Standard 301-201x.

“(b) For homes with one- and two-family dwellings with conditioned basements and for multi-family attached homes dwelling units in residential buildings not over three stories in height above grade containing multiple dwelling units the following formula shall be used to determine total window area:”

 

 

 

Comment #59

Page Number: 16
Paragraph / Figure / Table / Note: table 4.2.1(1) note (b)
Comment Type: Editorial

Comment:

 

Clarification and increased uniformity in application and use.

Proposed Change:

 

The terms/phrases “above-grade boundary wall” and above-grade thermal boundary gross wall” are used and not defined.  “Above-grade thermal boundary wall” is defined.  These phrases may be intended to mean the same thing, but it is not clear. They should all be defined or the text in some way clarified.  As covered in other comments, it is more appropriate to define terms in Section 3 on definitions and not throughout the standard. 

Response:

Accepted. Definitions for wall types used in Table 4.2.1(1), note (b) will be modified to make the definitions consistent with the equation equalities in the final committee draft of BSR/RESNET Standard 301-201x. Since these wall type definitions pertain only to the calculation provided by note (b), and the terms are not used elsewhere in the Standard, there is no need to provide definitions for these wall types within Section 3 of the Standard. The revised text in question will read as follows:
“where:
AF = Total fenestration area
CFA = Total floor area of directly conditioned space
FA = (Gross above-grade thermal boundary wall area) / (gross above-grade thermal boundary wall area + 0.5 x gross below-grade thermal boundary wall area)
F = 1- 0.44* (gross common wall area) / (gross above-grade thermal boundary wall area + gross common wall area)

and where:
Thermal boundary wall is any wall that separates conditioned space from unconditioned space or ambient conditions
Above-grade thermal boundary wall is any portion of a thermal boundary wall not in contact with soil.
Below-grade thermal boundary wall is any portion of a thermal boundary wall in soil contact
Common wall is the total wall area of walls adjacent to another conditioned living unit, not including foundation walls.”

Comment #60

Page Number: 16
Paragraph / Figure / Table / Note: table 4.2.1(1) note (c)
Comment Type: Editorial

Comment:

 

Clarification and increased ease of application and use.

Proposed Change:

 

Replace “due south” with either plain “south” or, if needed to clarify magnetic declination issues, “true south.”

Response:

Accepted. Global search and replace will be used to replace “due south” with “true south” in the final committee draft of BSR/RESNET Standard 301-201x.

Comment #61

Page Number: 16
Paragraph / Figure / Table / Note: table 4.2.1(1) note (d)
Comment Type: Technical

Comment:

 

ASHRAE Standard 119 was withdrawn in 2012 and as such no longer exists.

Proposed Change:

 

Delete the footnote as presented and find an alternative note that will address the intent of the standard.

Response:

Accepted.  BSR/RESNET Standard 301-201x, Table 4.2.1(1), Note (d) will be modified to reflect the correct reference for the calculation, which is now found in Section 4.1.2 of ASHRAE Standard 62.2.

Comment #62

Page Number: 16
Paragraph / Figure / Table / Note: table 4.2.1(1) note (e)
Comment Type: General

Comment:

 

See comments to Equation 4.1-1.  It is inappropriate to list a specific conformity assessment agency or organization by name in standard.  This issue is addressed through the use of terms such as “approved” and “nationally recognized” and then as warranted federal, state or local agencies that formulate and implement associated laws and regulations will determine the degree to which they would verify the continued acceptance of any third parties and continue to allow them to conduct testing, certification, etc. work associated with conformity assessment on behalf of those adopting entities.  Inclusion of RESNET in this standard within the context that the only entity that can conduct such testing is a rater certified by RESNET (see defined term in Section 3) should be seriously considered and removed in place of the suggested use of “approved” and its definition.  As currently presented in the standard RESNET certification is listed as the only acceptable conformity assessment method as a first-party entity (e.g. self-certification and accreditation) with respect to its ability to perform the stated services on a continuing (e.g. in perpetuity) basis.  This is something that accrediting entities such as ANSI, NAVLAP, IAS and others are actively engaged in on an ongoing basis as third party accrediting entities. As such they could assess any RESNET certification programs separately and through certification RESNET could be recognized as an “approved” entity.  Inclusion of a first party conformity assessment entity or accrediting agency as RESNET is in the standard opens up the question for users – who then provides oversight of those agencies ongoing activities to ensure they meet standards for conformity assessment entities and should continue to be “approved”.   

Also for consideration, where any conformity assessment program is mentioned by name in a standard, whether adopted on a voluntary or mandatory basis, the adoption of the standard results in a defacto acceptance of the named conformity assessment program in perpetuity; that is something that can change in the future to be accepted now.  This could adversely affect the adoption and use of the standard and for that reason, as in the comment on Equation 4.1-1, it is suggested that the issue of certification and accreditation be decoupled from the standard through the use of “approved” and “nationally recognized”.

Proposed Change:

 

(e) Tested envelope leakage shall be determined and documented by a Certified Rater using the on-site inspection protocol as specified in Appendix A, Mortgage Industry National Home Energy Rating Systems Standards under “Blower Door Test.by an approved testing agency. Either hourly calculations using the procedures given in the 2001 ASHRAE Handbook of Fundamentals, Chapter 26, page 26.21, equation 40 (Sherman-Grimsrud model) or calculations yielding equivalent results shall be used to determine the energy loads resulting from air exchange.

Response:

Accepted as modified. The comment is modified to retain the specified air exchange rate calculation method and update the calculation specifications to the most current reference, as follows:

“(e) Tested envelope leakage shall be determined and documented by a Certified Rater using the on-site inspection protocol as specified in Appendix ASection 802, Mortgage Industry National Home Energy Rating Systems Standards under “Blower Door Test.” by an Approved Tester. Either hourly calculations using the procedures given in the 20012009 ASHRAE Handbook of Fundamentals, Chapter 2616, page 26.2116.23, equation 4048 (Sherman-Grimsrud model) or calculations yielding equivalent results shall be used to determine the energy loads resulting from air exchange rate.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

 

Comment #63

Page Number: 16
Paragraph / Figure / Table / Note: table 4.2.1(1) note (g)
Comment Type: General

Comment:

 

If the term thermal storage element is used more than one place in the standard it may be advisable to include a definition of thermal storage element in Section 3, thereby eliminating the need to define the term where used throughout the standard. What is proposed is more in alignment with a definition, although the criteria in the note associated with the limitations of the storage in terms of installation would be appropriate for the note.  Also note the existence of a definition ensures uniform and consistent application and use of the standard with respect to the defined terms that can be compromised if the terms are defined/redefined each time they appear in the standard.  In addition if those terms are used somewhere in the standard and not defined it is unclear without a definition how they would be defined.

Proposed Change:

 

Note (g) seems more appropriate as a definition. 

Response:

Rejected. The term “thermal Storage element” is used only in Table 4.2.1(1) so there is no need to include its definition in Section 3 of BSR/RESNET Standard 301-201x.
You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #64

Page Number: 16
Paragraph / Figure / Table / Note: table 4.2.1(1) note (h) (1)
Comment Type: Editorial

Comment:

 

Clarification and increased ease of use.

Proposed Change:

 

Phrases such as “…is found in the Rated Home” may be confusing because the Rated Home will always initially be a design only.  “Found” implies something identified in an existing home.  Consideration should be given to revising the text so it can be applied in the design phase. 

Response:

Accepted. The words “is found” will be stricken and the text will be adjusted accordingly in the final committee draft of BSR/RESNET Standard 301-201x, as follows:

“. . . . For the HERS Reference Home, the minimum efficiencies given in Table 4.2.2(1a) below will be assumed for:

1) A type of device not covered by NAECA in the Rated Home;

2) A Rated Home heated by electricity using a device other than an air source heat pump; or

3) A Rated Home that does not contain one or more of the required HVAC equipment systems.”

Comment #65

Page Number: 16
Paragraph / Figure / Table / Note: table 4.2.1(1) note (h), (i), (k) and (m)
Comment Type: Technical

Comment:

 

The term “prevailing federal minimum efficiency” is vague, undefined and will be subject to interpretation leading to increased mis-application of the standard.  Beyond that it forces all users to research and determine what that efficiency might be.  All federal rules are delineated in the Code of Federal Regulations (CFR) and should be specifically referenced to the CFR Title and Part by number and name. 

Proposed Change:

 

Replace the term “prevailing federal minimum efficiency” with a specific citation to the Code of Federal Regulations.

Response:

Accepted. Table 4.2.1(1) notes (h), (i), (k), and (m) will be adjusted accordingly in the final committee draft of BSR/RESNET Standard 301-201x, as follows:

(h)  For a Rated Home with multiple heating, cooling, or water heating systems using different fuel types, the applicable system capacities and fuel types shall be weighted in accordance with the loads distribution (as calculated by accepted engineering practice for that equipment and fuel type) of the subject multiple systems. For the HERS Reference Home, the minimum efficiencies given in Table 4.2.2(1a) below will be assumed for:

1)  A type of device not covered by NAECA in the Rated Home;

2)  A Rated Home heated by electricity using a device other than an air source heat pump; or

3)  A Rated Home that does not contain one or more of the required HVAC equipment systems.

(i)  For a Rated Home without a proposed heating system, a heating system with the efficiency provided in Table 4.2.2(1a) shall be assumed for both the HERS Reference Home and Rated Home.  For electric heating systems, the efficiency air-source heat pump shall be selected.

(k)  For a Rated Home without a proposed cooling system, an electric air conditioner with the efficiency provided in Table 4.2.2(1a) shall be assumed for both the HERS Reference Home and the Rated Home.

(m)  For a Rated Home with a non-storage type water heater, a 40-gallon storage-type water heater of the same fuel as the proposed water heater shall be assumed for the HERS Reference Home. For tankless water heaters, the Energy Factor (EF) for shall be multiplied by 0.92 for Rated Home calculations. For a Rated Home without a proposed water heater, a 40-gallon storage-type water heater of the same fuel as the heating fuel type used for the heating system shall be assumed for both the Rated and HERS Reference Homes. In both cases the Energy Factor of the water heater shall be as prescribed for water heaters by CFR 430.32(d), published in the Federal Register/Volume 66, No. 11, Wednesday, January 17, 2001 for water heaters manufactured after January 20, 2004.

Comment #66

Page Number: 16
Paragraph / Figure / Table / Note: table 4.2.1(1) note (h) (1)
Comment Type: Editorial

Comment:

 

NAECA is not defined nor described in the standard.  While many users will understand what this means others may not.  More importantly if the intent is to have this standard adopted and used, whether on a mandatory or voluntary basis, what is presented in the standard needs to be crystal clear and not in need of any further interpretation or speculation as to intent or requirements.

Proposed Change:

 

Define the term NAECA.  It is not listed in Section 3 and is not defined as to what NAECA means.  The correct reference should be to a Public Law designation and included in the definitions, a list of acronyms and/or a listing of reference standards.

Response:

Accepted. The term NAECA will be defined with respect to the correct reference to Public law  in the final committee draft of BSR/RESNET Standard 301-201x.

Comment #67

Page Number: 17
Paragraph / Figure / Table / Note: Table 4.2.2(1a), Note (m)
Comment Type: Editorial

Comment:

 

The term “predominant” is subjective and not capable of being defined in a manner that would ensure consistency in the application and use of the standard.  For instance, is predominant based on the township, city, county, state or region of the country?  What is the statistical basis for that determination?  Without these specifically defined continued use of “predominant” will cause confusion. The proposed change addresses this issue in a clear manner that is less likely to cause confusion and non-uniform application of the standard.

Proposed Change:

 

(m) For a Rated Home with a non-storage type water heater, a 40-gallon storage-type water heater with the prevailing federal minimum efficiency and with the same fuel as the proposed water heater shall be assumed for the HERS Reference Home.  For a Rated Home without a proposed water heater, a 40-gallon storage-type water heater with the prevailing federal minimum efficiency with the same fuel as the predominant heating fuel type used for the heating system shall be assumed for both the Rated and HERS Reference Homes. 

Response:

Accepted. The proposed change will be incorporated in the final committee draft of BSR/RESNET Standard 301-201x. This change is also reflected in the Committee Response to Comment 65.

Comment #68

Page Number: 18
Paragraph / Figure / Table / Note: Table 4.2.2(1a), Note (n)
Comment Type: General

Comment:

 

See comments to Equation 4.1-1 and Table 4.2.2(1), Note (e).  It is inappropriate to list a specific conformity assessment agency or organization by name in standard.  This issue is addressed through the use of terms such as “approved” and “nationally recognized” and then as warranted federal, state or local agencies that formulate and implement associated laws and regulations will determine the degree to which they would verify the continued acceptance of any third parties and continue to allow them to conduct testing, certification, etc. work associated with conformity assessment on behalf of those adopting entities.  Inclusion of RESNET in this standard within the context that the only entity that can conduct such testing is a rater certified by RESNET (see defined term in Section 3) should be seriously considered and removed in place of the suggested use of “approved” and its definition.  As currently presented in the standard RESNET certification is listed as the only acceptable conformity assessment method as a first-party entity (e.g. self-certification and accreditation) with respect to its ability to perform the stated services on a continuing (e.g. in perpetuity) basis.  This is something that accrediting entities such as ANSI, NAVLAP, IAS and others are actively engaged in on an ongoing basis as third party accrediting entities. As such they could assess any RESNET certification programs separately and through certification RESNET could be recognized as an “approved” entity.  Inclusion of a first party conformity assessment entity or accrediting agency as RESNET is in the standard opens up the question for users – who then provides oversight of those agencies ongoing activities to ensure they meet standards for conformity assessment entities and should continue to be “approved”.   

 

Also for consideration, where any conformity assessment program is mentioned by name in a standard, whether adopted on a voluntary or mandatory basis, the adoption of the standard results in a defacto acceptance of the named conformity assessment program in perpetuity; that is something that can change in the future to be accepted now.  This could adversely affect the adoption and use of the standard and for that reason, as in the comment on Equation 4.1-1 and Table 4.2.2(1), Note (e), it is suggested that the issue of certification and accreditation be decoupled from the standard through the use of “approved” and “nationally recognized”.

Proposed Change:

 

n) Tested duct leakage shall be determined and documented by a Certified Rater an approved testing agency using the on-site inspection protocol as specified in Appendix A under “Air leakage (ducts)”.

There is also a reference to nonexistent ‘Appendix A under “Air leakage (ducts)”’ that should be clarified and corrected so it is clear what is being referred to and where it is in the document or in a reference document.

Response:

Accepted as modified. The comment is modified to provide the correct reference for duct leakage testing, as follows:

“n) Tested duct leakage shall be determined and documented by a Certified Rater an Approved Tester using the on-site inspection protocols as specified in Appendix A under “Air leakage (ducts)”Section 803, Mortgage Industry National Home Energy Rating Systems Standards.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #69

Page Number: 18
Paragraph / Figure / Table / Note: Table 4.2.2(1), Note (o)
Comment Type: Technical

Comment:

 

Clarification of intent.  Also of note the term “biomass fuel” does not appear to be defined, which will lead to probable interpretation and confusion.  In addition the use of “should” in a standard ensures that the intent to standardize ratings will not occur.  A standard such as this must provide specific and clear criteria if the continuity and uniformity envisioned in HERS ratings is to be realized.  The use of the term “house” is confusing (see  prior comments on scope and definition of residential) and could lead many users to presume that dwelling units in multi-family buildings are not addressed.  This raises another key issue that may need consideration here and in other parts of the standard – how does this standard address multi-family buildings where there are multiple dwelling units that are served by a singular central heating, cooling and/or service hot water system?

Proposed Change:

 

(o) Biomass fuel systems should shall not be included in ratings when they are considered “supplemental systems”, i.e. where an automatic only when a permanent heating system, sized to meet the load of the house dwelling unit does not exists. Biomass systems should only be included in the rating in those situations where the automatic heating system is not large enough to meet the load of the house, and a biomass fuel system is in place to meet the balance of the load, or where there is only a biomass fuel system in place. In the situation where there are two systems that together meet the load, Where installed to supplement a permanent heating system that cannot meet the load of the dwelling unit the biomass system shall be assigned only that part of the load that cannot be met by the automatic  permanent heating system.

Response:

Accepted. The proposed change will be incorporated in the final committee draft of BSR/RESNET Standard 301-201x and “Biomass Fuel” will also be added as a defined term in the definitions, as follows:

Biomass Fuel – Plant materials that have been processed to be capable of providing useful heat through combustion.”

Comment #70

Page Number: 18
Paragraph / Figure / Table / Note: Table 4.2.2(2), Note (b)
Comment Type: Editorial

Comment:

 

Standards should refer to the specific reference document by name and in a reference standards section refer to the edition of use.  In referring to the IECC the latest edition (2012) is the most appropriate reference because among others it will be available when prior editions are less likely to be available or accessible. It should be noted that Note (a) to Table 4.2.2(4) refers to the 2000 IECC.  The referencing of multiple (and in this case older) editions of the same document should be eliminated.   If anything this will adversely affect the use of this document by requiring users to secure multiple different older editions of the IECC.  In addition should RESNET desire this standard and the resultant ratings to be acceptable in lieu of state or local energy codes, the standard should refer to the lasted published edition of any reference standards.  The appropriate format for this is to name the document in the text without any edition date and then in a reference standards section include the full title, edition date, publisher and other related information appropriate for knowing what the standard is and where it can be obtained.

 

Proposed Change:

 

(b) Climates zones shall be as specified by the 2004 Supplement to the International Energy Conservation Code.

Response:

Accepted. Table 4.2.2(4) will be removed from the standard through acceptance of Comment #6.

Comment #71

Page Number: 19
Paragraph / Figure / Table / Note: Table 4.2.2(4), Note (a)
Comment Type: Editorial

Comment:

 

Note (a) is informative and is not needed.  The default numbers are what they are and there is no reason to explain where they came from in the standard.  This raises the issue of lack of similar background for other provisions in the standard; all of which could be included in an informative appendix to the standard or a separate background document.

Proposed Change:

 

Table 4.2.2(4), Note (a)

Response:

Rejected. Table 4.2.2(4) will not be incorporated in the final committee draft of BSR/RESNET Standard 301-201x due to Committee acceptance of public comment #6 recommending its deletion.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #72

Page Number: 20
Paragraph / Figure / Table / Note: Table 4.2.2(4), Note (c)
Comment Type: Technical

Comment:

 

There is no definition of conditioned space. This along with the definition of building thermal envelope is critical to the application and use of the IECC.  The intent seems clear and in lieu of defining those terms the proposed change makes the intent as to when duct systems are inside the building envelope or not (e.g. in conditioned space).  Alternatively consideration should be given to defining the terms conditioned space and building thermal envelope, both of which are defined in energy codes and standards and whose definitions are critical to the uniform application and use of those documents.

Proposed Change:

 

(c) Entire system in conditioned space shall mean that no component of the distribution system, including the air handler unit or boiler, is located outside of the conditioned space boundary spaces of the dwelling unit that are heated and/or cooled.

Response:

 

Accepted in part.  Table 4.2.2(4) will not be incorporated in the final committee draft of BSR/RESNET Standard 301-201x due to SDC acceptance of public comment #6 recommending its deletion.  However, the SDC has determined that the comment warrants revision or addition of the following four inter-related definitions in Section 3 of BSR/RESNET Standard 301-201x.

 

Conditioned Floor Area (CFA) – The projected floor area of the Conditioned Space within a building measured in accordance with ANSI Standard Z765-2012 with exceptions as specified in Appendix A of the Mortgage Industry National Home Energy Rating Systems Standards.

 

Conditioned Space – An area or room within a building serviced by a space heating or cooling system designed to maintain human comfort in accordance with ASHRAE Standard 55-2010.

 

Conditioned Space Boundary – The principal air containment planes of a building that separate the Conditioned Space within the building from Unconditioned Space.

 

Unconditioned Space – The outdoor environment or an area or room within a building that is not Conditioned Space but which may contain heat sources or sinks that influence the temperature of the area or room.

 

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #73

Page Number: 20
Paragraph / Figure / Table / Note: Table 4.2.2(4), Note (d)
Comment Type: Technical

Comment:

 

The provisions “substantially leak free” and “leakage less than 3 cfm per 100 sf” is contradictory and inconsistent.  The former is subjective and indeterminate in any uniform manner while the latter is specific and determinant.  The proposed change addresses this issue and enhances the standard by retaining the more specific of the two criteria.  There is no need for the second sentence as it repeats the criteria of the first sentence.

The last sentence is revised for clarity and to address the issue of inappropriately embedding professional qualifications and credentialing inside this type of standard.  For instance see comments to Equation 4.1-1 and Table 4.2.2(1), Note (e).  It is inappropriate to list a specific conformity assessment agency or organization by name in standard.  This issue is addressed through the use of terms such as “approved” and “nationally recognized” and then as warranted federal, state or local agencies that formulate and implement associated laws and regulations will determine the degree to which they would verify the continued acceptance of any third parties and continue to allow them to conduct testing, certification, etc. work associated with conformity assessment on behalf of those adopting entities.  Inclusion of RESNET in this standard within the context that the only entity that can conduct such testing and documentation is a rater certified by RESNET (see defined term in Section 3) should be seriously considered and removed in place of the suggested use of “approved” and its definition.  As currently presented in the standard RESNET certification is listed as the only acceptable conformity assessment method as a first-party entity (e.g. self-certification and accreditation) with respect to its ability to perform the stated services on a continuing (e.g. in perpetuity) basis.  This is something that accrediting entities such as ANSI, NAVLAP, IAS and others are actively engaged in on an ongoing basis as third party accrediting entities. As such they could assess any RESNET certification programs separately and through certification RESNET could be recognized as an “approved” entity.  Inclusion of a first party conformity assessment entity or accrediting agency as RESNET is in the standard opens up the question for users – who then provides oversight of those agencies ongoing activities to ensure they meet standards for conformity assessment entities and should continue to be “approved”.   

Also for consideration, where any conformity assessment program is mentioned by name in a standard, whether adopted on a voluntary or mandatory basis, the adoption of the standard results in a defacto acceptance of the named conformity assessment program in perpetuity; that is something that can change in the future to be accepted now.  This could adversely affect the adoption and use of the standard and for that reason, as in the comment on Equation 4.1-1 and Table 4.2.2(1), Note (e), it is suggested that the issue of certification and accreditation be decoupled from the standard through the use of “approved” and “nationally recognized”.

Proposed Change:

 

(d) Proposed “reduced leakage” shall mean substantially leak free to be leakage of not greater than 3 cfm to outdoors per 100 square feet of conditioned floor area and not greater than 9 cfm total air leakage per 100 square feet of conditioned floor area at a pressure differential of 25 Pascal across the entire system, including the manufacturer’s air handler enclosure. Total air leakage of not greater than 3 cfm per 100 square feet of conditioned floor area at a pressure difference of 25 Pascal across the entire system, including the manufacturer’s air handler enclosure, shall be deemed to meet this requirement without measurement of air leakage to outdoors. This rated condition shall be specified as “reduced leakage” the required performance in the construction documents and requires confirmation compliance confirmed through field-testing of installed systems as documented by a Certified Rater an approved testing agency.

Response:

Accepted as modified.  Table 4.2.2(4) and its notes will be removed from BSR/RESNET Standard 301-201x based on acceptance of public comment #6.

Comment #74

Page Number: 20
Paragraph / Figure / Table / Note: Table 4.2.2(4), Note (e)
Comment Type: Editorial

Comment:

 

The language as drafted is permissive and not appropriate for a standard where uniformity, consistency and clarity in the application of the standard are desired. 

Proposed Change:

 

(e) Ductless systems may have having forced airflow across a coil but shall not have any ducted airflows external to the manufacturer’s air handler enclosure. 

Response:

Rejected. Table 4.2.2(4) will not be incorporated in the final committee draft of BSR/RESNET Standard 301-201x due to Committee acceptance of public comment #6 recommending its deletion.

You have the right to file an appeal within 30 days with the RESNET Standards Management Board in accordance with Section 12 of the RESNET Standards Development Policy and Procedures Manual.

Comment #75

Page Number: 20
Paragraph / Figure / Table / Note: Section 4.2.2.1
Comment Type: Editorial

Comment:

 

The intent is clearly to have the user of the standard apply the framing fractions in the table.  The proposed revisions communicate that intent and direction and eliminate text that is not needed and could detract from the desirability of the standard.  

Proposed Change:

 

4.2.2.1. All enclosure elements shall use framing fractions that are consistent with and representative of reality.  Default enclosure framing fractions are provided by shall be in accordance with Table 4.2.2(6).

Response:

Accepted. The proposed change will be incorporated in the final committee draft of BSR/RESNET Standard 301-201x.

Comment #76

Page Number: 21
Paragraph / Figure / Table / Note: Section 4.2.2.2.1
Comment Type: Editorial

Comment:

 

It is unclear how this section is to be applied as inspection is most likely to occur after modeling.  The standard should be clarified to indicate the sequence in which inspection and modeling are conducted in order to arrive at a rating is intended to occur.  One way to do that would be to write a new section 4 on compliance and outline therein an overview of the standard and how the rating is to be determined and compliance as to the validity of the rating in the actual construction is ensured.

The revision to exception (a) is intended to eliminate permissive language and strengthen the intent of the document.  It is noted that the inclusion of where DAPIA packages may be submitted is likely moot as to application of this standard, unless the intent is to apply this standard over and above the HUD Code (24 CFR Part 3280).  Of particular note, this exception applies to both manufactured and modular construction.  Since modular construction is not regulated by HUD but instead state laws and regulations, why have the standard require DAPIA approved packages for modular homes to be sent to HUD?

Exception (b) is not worded as an exception because it actually contains criteria that are attached to the exception.  The proposed change more clearly states the intent in a more appropriate format for an exception to the requirements in the standard.  The word “similar” is subjective and should not be used in a standard if standardization with respect to HERS and clarity and uniformity of use are desired.

Exception (c) is deleted.  As commented in previous sections (i.e. Equation 4-1.1) the inclusion of a conformity assessment entity by name  is not appropriate.  The exception is stated in permissive terms because the entity that can invoke “may” is not stated. In addition the “conditions specified in the RESNET approval process” is an open ended provision that could adversely affect the adoption and use of the standard.  What is the process and more specifically what is the date certain of that process.  A standard with a date certain approval and publication date cannot adopt by reference something that is not specifically defined as to a publication with a specific publication date. 

 

Proposed Change:

 

4.2.2.2.1. The HERS Reference Home enclosure elements shall be modeled assuming Grade I insulation.  Default values for Rated Home insulation that is not inspected according to the procedures of Appendix A, Mortgage Industry National Home Energy Rating Systems Standards shall be in accordance with the requirements of Grade III as given in Section 4.2.2.2.2 and shall be recorded as “not inspected” in the rating information.

Exceptions:

(a) Modular and manufactured housing using IPIA (In-Plant Inspection Agent) inspections may be substituted shall be considered as an acceptable alternative for the HERS inspection. However, housing where the manufacturer shall include of the home includes RESNET insulation inspection details and requirements in their “DAPIA” (Design Approval Primary Inspection Agency) packages submitted to HUD which are used by IPIA’s for their factory inspections.

 (b) The R-values for Structural Insulated Panels (SIP’s), Insulated Concrete Forms (ICF’s), and other similar insulated pre-manufactured assemblies when accompanied by supporting test data. Note that manufacturer’s claims of “equivalent” R-values based on reduced air leakage or other secondary effects may not be used; only the thermal resistance values for the actual materials as found in ASHRAE Handbook of Fundamentals may be used.

 (c) A RESNET-approved, third-party audited installer certification program may be substituted under the conditions specified in the RESNET approval process.

Response:

Accepted. The proposed change will be incorporated in the final committee draft of BSR/RESNET Standard 301-201x.

Comment #77

Page Number: 22
Paragraph / Figure / Table / Note: Section 4.2.2.2.2
Comment Type: Editorial

Comment:

 

The intent appears to be a listing of four caveats to the provisions in Section 4.2.2.2.2 and as such the subsequent sections should not have a parallel numerical designation but actually listed as subsections to the parent section (4.2.2.2.2).   Section 4.2.2.2.4 is revised editorially to improve the usability of the standard.  For the convenience of the user the correction factors should be provided in the standard.  If the reference to another document is retained it should be to the document by name, publication date and the specific criteria therein (e.g. section number).  The date of publication should not be listed within the provisions of the standard but in a section on reference standards, which also applies to Section 4.2.2.2.6 and a number of other sections in the standard where other documents are referenced; some of which have different edition dates associated with the same reference.  Section 4.2.2.2.5 is revised to more clearly state the intent.  The use of the term “large” is subjective and indeterminate.  In addition it is not appropriate to put informative notes in a standard.  The standard must first be as clear and precise as to the requirements so no such notes are needed.  If application and use of the standard is desired and there is a desire for notes or related support information then a separate commentary could be produced or the issue needing notes addressed in a Foreword to the standard. It is also important and critical to note the reference to the 2009 ASHRAE Handbook of Fundamentals.  Other portions of this standard refer to the 2001 edition and still others refer to that document without any edition date.  As covered above and in other comments, this issue should be addressed throughout the standard and is one of a number of areas that if left as proposed could detract from the adoptability, acceptability and use of the standard. 

Proposed Change:

 

4.2.2.2.2. Insulation Assessment:  Insulated surfaces categorized as “Grade I” shall be modeled such that the insulation R-value within the cavity is considered at its measured (for loose fill) or labeled value, including other adjustments such as compression, and cavity fill versus continuous, for the insulated surface area (not including framing or other structural materials which shall be accounted for separately). Insulated surfaces categorized as "Grade II" shall be modeled such that there is no insulation R-value for 2% of the insulated surface area and its measured or labeled value, including other adjustments such as compression and cavity fill versus continuous, for the remainder of the insulated surface area (not including framing or other structural materials). Insulated surfaces categorized as "Grade III" shall be modeled such that there is no insulation R-value for 5% of the insulated surface area and its measured or labeled value, including other adjustments such as compression and cavity fill versus continuous, for the remainder of the insulated surface area (not including framing or other structural materials). Other building materials, including framing, sheathing, and air films shall be assigned aged or settled -values according to ASHRAE Fundamentals.  In addition, the following accepted conventions shall be used in modeling Rated Home insulation enclosures:

4.2.2.2.3. a. Insulation that does not cover framing members shall not be modeled as if it covers the framing. Insulated surfaces that have continuous insulation (i.e. rigid foam, fibrous batts, loose fill, or sprayed insulation) covering the framing members shall be assessed and modeled according to Section 4.2.2.2 and combined with the cavity insulation, framing and other materials to determine the overall assembly R-value.

4.2.2.2.4. b. Compression: for modeling purposes, the The base R-value of fibrous insulation that is compressed to less than its full rated thickness in a completely enclosed cavity shall be assessed according to the manufacturer's documentation; in the absence of such documentation, use R-value correction factor (CF) for Compressed Batt or Blanket from Manual J, 8th edition Table A5-1, Section 7-d.

4.2.2.2.5. c. Where large areas of insulation that is missing, or has a different R-value from the rest of an assembly exist, these areas  Areas of an assembly having different insulation types or R-values shall be modeled separately with the appropriate applicable R-value and assembly description separately from the rest of the assembly. Insulation R-values may not be averaged according to coverage area. For example, if 50 square feet of a wall area has no cavity fill insulation at all, that 50 square feet shall be recorded as a separate building component with no cavity insulation, but with the existing structural components area associated with each different insulation situation.

4.2.2.2.6. d. Steel framing in insulated assemblies: calculations for the<