The following comments have been submitted:
Comment #1Page Number: 1Comment Intent: ObjectionComment Type: GeneralComment: By creating a new Index type, to join the Energy Rating Index and the Water Index, it should follow that this is a completely different standard, rather than "in addition to" the ERI calculation. Proposed Change: Create a completely new standard (like ANSI/RESNET/ICC 850) instead of stuffing this into ANSI/RESNET/ICC-301.
By creating a new Index type, to join the Energy Rating Index and the Water Index, it should follow that this is a completely different standard, rather than "in addition to" the ERI calculation.
Create a completely new standard (like ANSI/RESNET/ICC 850) instead of stuffing this into ANSI/RESNET/ICC-301.
Comment #2Page Number: 1Comment Intent: ObjectionComment Type: GeneralComment: Due to the CO2 Index using a different configuration of reference home (using an all-electric reference home) from the default ERI reference home logic, even if it uses 95% of the same equations, it should be a completely different standard. Proposed Change: Write a completely new ANSI standard, instead of trying to shove additional calculations into ANSI 301 for "ease".
Due to the CO2 Index using a different configuration of reference home (using an all-electric reference home) from the default ERI reference home logic, even if it uses 95% of the same equations, it should be a completely different standard.
Write a completely new ANSI standard, instead of trying to shove additional calculations into ANSI 301 for "ease".
Comment #3Page Number: 1Comment Intent: ObjectionComment Type: GeneralComment: The literal title of ANSI-301 is "Standard for the Calculation and Labeling of the Energy Performance of Dwelling and Sleeping Units using an Energy Rating Index". By adding a completely new Index "type", the additional calculations/equations are completely out of line. Proposed Change: Start a new ANSI standard for a CO2 Index instead of shoving it into a similar but entirely different-purposed standard.
The literal title of ANSI-301 is "Standard for the Calculation and Labeling of the Energy Performance of Dwelling and Sleeping Units using an Energy Rating Index". By adding a completely new Index "type", the additional calculations/equations are completely out of line.
Start a new ANSI standard for a CO2 Index instead of shoving it into a similar but entirely different-purposed standard.
Comment #4Page Number: 1Paragraph / Figure / Table / Note: NAComment Intent: Not an ObjectionComment Type: GeneralComment: This standard identifies the metrics, tolerances, procedures, calculations and the required documentation to: (1) calculate the standard energy use of Dwelling Units and Sleeping Units, (2) determine the Energy Rating Index of Dwelling Units and Sleeping Units, (3) determine the CO2 Index of Dwelling Units and Sleeping Units, (4) define the minimum rated features of Dwelling Units and Sleeping Units, (5) calculate the retrofit savings for existing Dwelling Units and Sleeping Units, (6) calculate the cost effectiveness of energy saving improvements to Dwelling Units and Sleeping Units and (7) label the certified energy performance of Dwelling Units and Sleeping Units. RECCOMENDATION We support the addition of the CO2 rating index and support adding this index in a prominent place on the HERS certificate. While an Energy Rating Index can indicate the level of contribution to climate change, a CO2 index will directly communicate how a particular home contributes to climate change and will give buyers a clear picture of their architectural carbon footprint. We support including this on every HERS certificate in a prominent place with no option to delete or hide the CO2 Rating Index. By including this in Std 301- 2019 it will be referenced as the standard to use for home built under the 2021 IECC.
This standard identifies the metrics, tolerances, procedures, calculations and the required documentation to: (1) calculate the standard energy use of Dwelling Units and Sleeping Units, (2) determine the Energy Rating Index of Dwelling Units and Sleeping Units, (3) determine the CO2 Index of Dwelling Units and Sleeping Units, (4) define the minimum rated features of Dwelling Units and Sleeping Units, (5) calculate the retrofit savings for existing Dwelling Units and Sleeping Units, (6) calculate the cost effectiveness of energy saving improvements to Dwelling Units and Sleeping Units and (7) label the certified energy performance of Dwelling Units and Sleeping Units.
RECCOMENDATION
We support the addition of the CO2 rating index and support adding this index in a prominent place on the HERS certificate. While an Energy Rating Index can indicate the level of contribution to climate change, a CO2 index will directly communicate how a particular home contributes to climate change and will give buyers a clear picture of their architectural carbon footprint. We support including this on every HERS certificate in a prominent place with no option to delete or hide the CO2 Rating Index. By including this in Std 301- 2019 it will be referenced as the standard to use for home built under the 2021 IECC.
Comment #5Page Number: Pierre DelforgeParagraph / Figure / Table / Note: Pierre DelforgeComment Intent: Not an ObjectionComment Type: TechnicalComment: On behalf of the Natural Resources Defense Council (NRDC), we submit the following comments on RESNET’s draft CO2 rating index. RESNET standards are instrumental for both code compliance and market-based programs throughout North America, and with this change would be offering the first policy-appropriate greenhouse gas metric for building performance. NRDC strongly supports the requirements of this section as proposed and urge you to retain it. Specifically, please retain the reliance on long term marginal hourly emissions by geographic area levelized over the years 2025-2055, and retain the requirement that the reference house use electricity for all end uses. A rated house, whether new or retrofit, will be in existence for over 100 years, so a forward-looking calculation is needed. By the time this provision is approved and used, we will already be in the year 2022 so starting earlier than 2025 doesn’t make sense, especially given that RESNET should retain the same methods for at least 5-10 years to enhance comparability between different rated homes. The purpose of this amendment is to give more meaningful advice when a home is audited and rated as to what measures can reduce pollution emissions, including reducing them to net zero. There are three methods of doing this: reducing energy consumption overall, changing the timing of emissions to correspond with hours in which the grid is cleaner, and changing to a low carbon fuel. The only way we can achieve the third objective is to include the effects of fuel switching between fossil and electric in the emissions rating. Thus the objective of making fuel choice not affect the HERS rating is no longer justified when we are evaluating carbon emissions. Comparing all homes to the same baseline in terms of fuel choice is necessary if we are to evaluate in the rating the effects of different fuels comparatively. Electricity is a logical choice for a single-fuel reference house because it is universally available for all homes.
On behalf of the Natural Resources Defense Council (NRDC), we submit the following comments on RESNET’s draft CO2 rating index. RESNET standards are instrumental for both code compliance and market-based programs throughout North America, and with this change would be offering the first policy-appropriate greenhouse gas metric for building performance.
NRDC strongly supports the requirements of this section as proposed and urge you to retain it. Specifically, please retain the reliance on long term marginal hourly emissions by geographic area levelized over the years 2025-2055, and retain the requirement that the reference house use electricity for all end uses.
A rated house, whether new or retrofit, will be in existence for over 100 years, so a forward-looking calculation is needed. By the time this provision is approved and used, we will already be in the year 2022 so starting earlier than 2025 doesn’t make sense, especially given that RESNET should retain the same methods for at least 5-10 years to enhance comparability between different rated homes.
The purpose of this amendment is to give more meaningful advice when a home is audited and rated as to what measures can reduce pollution emissions, including reducing them to net zero. There are three methods of doing this: reducing energy consumption overall, changing the timing of emissions to correspond with hours in which the grid is cleaner, and changing to a low carbon fuel. The only way we can achieve the third objective is to include the effects of fuel switching between fossil and electric in the emissions rating.
Thus the objective of making fuel choice not affect the HERS rating is no longer justified when we are evaluating carbon emissions. Comparing all homes to the same baseline in terms of fuel choice is necessary if we are to evaluate in the rating the effects of different fuels comparatively. Electricity is a logical choice for a single-fuel reference house because it is universally available for all homes.
Comment #6Page Number: 3Paragraph / Figure / Table / Note: Sections 6.2 and 6.4Comment Intent: Not an ObjectionComment Type: GeneralComment: EPA’s ENERGY STAR Residential Branch supports the proposal to create the CO2 Rating Index, in general, and specifically supports: The proposal in Section 6.2 to use Levelized Long-Run Marginal Emissions Rates from Cambium’s Low Renewable Energy Cost Scenario, and, The proposal in Section 6.4 to configure the CO2 Index Reference Home with electricity for all energy end-uses. These two elements of the proposal are essential to ensuring that the CO2 Rating Index accurately reflects the impact of a home. Many rated features of a home, particularly in new homes which comprise over 95% of HERS ratings, have a lifetime of one to three decades. Therefore, emissions rates that reflect long-term projections of the electric grid must be used. Furthermore, one key use-case of this rating index will be to support policies that address the decarbonization of the residential sector. Using electricity for all energy end-uses will provide a consistent baseline from which to measure improvements. We strongly recommend that both elements of the proposal be maintained Proposed Change: None.
EPA’s ENERGY STAR Residential Branch supports the proposal to create the CO2 Rating Index, in general, and specifically supports:
These two elements of the proposal are essential to ensuring that the CO2 Rating Index accurately reflects the impact of a home.
Many rated features of a home, particularly in new homes which comprise over 95% of HERS ratings, have a lifetime of one to three decades. Therefore, emissions rates that reflect long-term projections of the electric grid must be used.
Furthermore, one key use-case of this rating index will be to support policies that address the decarbonization of the residential sector. Using electricity for all energy end-uses will provide a consistent baseline from which to measure improvements.
We strongly recommend that both elements of the proposal be maintained
None.
Comment #7Page Number: 1Paragraph / Figure / Table / Note: Section 5.1.2.2Comment Intent: ObjectionComment Type: TechnicalComment: EPA’s ENERGY STAR Residential Branch recommends modifying the emissions calculations to align with the methodology proposed for the CO2 Rating Index. Specifically, we recommend that the same CO2 Index Reference Home be used, as well as the same levelized CO2 emissions factors. Many rated features of a home, particularly in new homes which comprise over 95% of HERS ratings, have a lifetime of one to three decades. Therefore, emissions savings should reflect long-term projections of the electric grid. Furthermore, emissions savings should be calculated using a methodology consistent with that used for the CO2 Rating Index to minimize confusion. As currently proposed, measures that improve the CO2 Rating Index value may not correspond with increased emissions savings. Alternatively, if this comment is not accepted, then consider adding a second emissions savings calculation that reflects this comment. In that way, users could choose to calculate emissions savings that suit their needs, either a short-term perspective with fuel types that align with the Rated Home or a long-term perspective with an all-electric baseline that aligns with the CO2 Rating Index. Proposed Change: Proposed edits relative to the amendment as drafted are shown in red. 5.1.2.2. Pollution Emission Savings. Where determined, the pollution emission savings for the Rated Home shall be calculated in accordance with Sections 5.1.2.2.1 and 5.1.2.2.2. 5.1.2.2.1. Pollution Emissions. Pollution eEmissions for all homes shall be calculated in accordance with Sections 5.1.2.2.1.1 and 5.1.2.2.1.2. 5.1.2.2.1.1. For electricity use, data for the sub-region annual total output emission rates published by Environmental Protection Agency’s 2012 2019 eGrid database[1] for electricity generation shall be used to calculate emissions.[2] except CO2 emissions, which shall be the levelized CO2 emission factors calculated using the Cambium database[3],[4] for the Low Renewable Energy Cost Scenario for the Long-Run Marginal enduse most recent year’s Mid-case, average hourly CO2 generation rate (co2_lmer_enduse co2_rate_avg_load_enduse: kgCO2 per MWhenduse) for the local ZIP Code using equation 6-2 with a starting year of 2025. 5.1.2.2.1.2. For fossil fuel use, pollution emissions shall be calculated using the emission factors given in Table 5.1.2(1). Table 5.1.2(1) National Average Emission Factors for Household Combustion Fuels Fuel Type Units MBtu per Unit CO2 lb/MBtu NOx lb/MBtu SO2 lb/MBtu Natural Gas Therm 0.1000 117.6 93.00.0922 0.00060 Fuel Oil #2 Gallon 0.1385 159.4161.0 127.80.1300 0.50660.0015 Liquid Petroleum Gas (LPG) Gallon 0.0915 136.46 153.40.1421 0.01630.0002 5.1.2.2.2. Pollution Emission Savings. Estimated pollution emission savings for the Rated Home shall be calculated in accordance with Sections 5.1.2.2.2.1 through 5.1.2.2.2.3. 5.1.2.2.2.1. The CO2 Index Reference Home shall be identical to the Energy Rating Reference Home except that it shall use electricity for all energy end uses. The Energy Rating Reference Home pollution emissions for the CO2 Index Reference Home shall be determined by fuel type by applying the emission factors pollution emissions determined in accordance with Section 5.1.2.2.1 to the its Purchased Energy individual fuel types of the Energy Rating Reference Home. 5.1.2.2.2.2. The Rated Home pollution emissions shall be determined by fuel type by applying the same pollution emission factors determined in accordance with data used for the Energy Rating Reference Home in Section 5.1.2.2.1.1 5.1.2.2.2.1 above. 5.1.2.2.2.3. For Confirmed, Sampled and Projected Ratings, estimated pollution emission savings shall be calculated in accordance with Sections 5.1.2.2.2.3.1 and 5.1.2.2.2.3.2. 5.1.2.2.2.3.1. Estimated pollution emission savings with respect to the Energy Rating Reference Home CO2 Index Reference Home shall be the difference between the pollution emissions of the Energy Rating Reference CO2 Index Reference Home Home and the pollution emissions of the Rated Home. 5.1.2.2.2.3.2. Estimated pollution emission savings with respect to the Typical Existing Home shall be determined in accordance with Sections 5.1.2.2.2.3.2.1 and 5.1.2.2.2.3.2.2. 5.1.2.2.2.3.2.1. For each fuel type, mMultiply the Energy Rating Reference Home pollution CO2 Index Reference Home emissions by 1.3 to determine the Typical Existing Home pollution emissions by fuel type. 5.1.2.2.2.3.2.2. Estimated pollution emission savings with respect to the Typical Existing Home shall be the difference between the pollution emissions of the Typical Existing Home and the pollution emissions of the Rated Home. [1] (Informative Reference) http://www.epa.gov/cleanenergy/energy-resources/egrid/index.html [2] (Informative Note) RESNET will compile and publish annual total output pollution emission rate data for NOx, SO2 and CO2 in accordance with the provisions of this section that can be used by Approved Software Rating Tools for the calculation of emissions. [3] https://cambium.nrel.gov/ [4] Gagnon, Pieter, Will Frazier, Elaine Hale, and Wesley Cole, 2020. “Cambium Documentation: Version 2020.” Golden, CO: National Renewable Energy Laboratory. NREL/TP-6A20-78239. https://www.nrel.gov/docs/fy21osti/78239.pdf
EPA’s ENERGY STAR Residential Branch recommends modifying the emissions calculations to align with the methodology proposed for the CO2 Rating Index. Specifically, we recommend that the same CO2 Index Reference Home be used, as well as the same levelized CO2 emissions factors.
Many rated features of a home, particularly in new homes which comprise over 95% of HERS ratings, have a lifetime of one to three decades. Therefore, emissions savings should reflect long-term projections of the electric grid.
Furthermore, emissions savings should be calculated using a methodology consistent with that used for the CO2 Rating Index to minimize confusion. As currently proposed, measures that improve the CO2 Rating Index value may not correspond with increased emissions savings.
Alternatively, if this comment is not accepted, then consider adding a second emissions savings calculation that reflects this comment. In that way, users could choose to calculate emissions savings that suit their needs, either a short-term perspective with fuel types that align with the Rated Home or a long-term perspective with an all-electric baseline that aligns with the CO2 Rating Index.
Proposed edits relative to the amendment as drafted are shown in red.
5.1.2.2. Pollution Emission Savings. Where determined, the pollution emission savings for the Rated Home shall be calculated in accordance with Sections 5.1.2.2.1 and 5.1.2.2.2.
5.1.2.2.1. Pollution Emissions. Pollution eEmissions for all homes shall be calculated in accordance with Sections 5.1.2.2.1.1 and 5.1.2.2.1.2.
5.1.2.2.1.1. For electricity use, data for the sub-region annual total output emission rates published by Environmental Protection Agency’s 2012 2019 eGrid database[1] for electricity generation shall be used to calculate emissions.[2] except CO2 emissions, which shall be the levelized CO2 emission factors calculated using the Cambium database[3],[4] for the Low Renewable Energy Cost Scenario for the Long-Run Marginal enduse most recent year’s Mid-case, average hourly CO2 generation rate (co2_lmer_enduse co2_rate_avg_load_enduse: kgCO2 per MWhenduse) for the local ZIP Code using equation 6-2 with a starting year of 2025.
5.1.2.2.1.2. For fossil fuel use, pollution emissions shall be calculated using the emission factors given in Table 5.1.2(1).
Table 5.1.2(1) National Average Emission Factors for Household Combustion Fuels
Fuel Type
Units
MBtu per Unit
CO2 lb/MBtu
NOx lb/MBtu
SO2 lb/MBtu
Natural Gas
Therm
0.1000
117.6
93.00.0922
0.00060
Fuel Oil #2
Gallon
0.1385
159.4161.0
127.80.1300
0.50660.0015
Liquid Petroleum Gas (LPG)
0.0915
136.46
153.40.1421
0.01630.0002
5.1.2.2.2. Pollution Emission Savings. Estimated pollution emission savings for the Rated Home shall be calculated in accordance with Sections 5.1.2.2.2.1 through 5.1.2.2.2.3.
5.1.2.2.2.1. The CO2 Index Reference Home shall be identical to the Energy Rating Reference Home except that it shall use electricity for all energy end uses. The Energy Rating Reference Home pollution emissions for the CO2 Index Reference Home shall be determined by fuel type by applying the emission factors pollution emissions determined in accordance with Section 5.1.2.2.1 to the its Purchased Energy individual fuel types of the Energy Rating Reference Home.
5.1.2.2.2.2. The Rated Home pollution emissions shall be determined by fuel type by applying the same pollution emission factors determined in accordance with data used for the Energy Rating Reference Home in Section 5.1.2.2.1.1 5.1.2.2.2.1 above.
5.1.2.2.2.3. For Confirmed, Sampled and Projected Ratings, estimated pollution emission savings shall be calculated in accordance with Sections 5.1.2.2.2.3.1 and 5.1.2.2.2.3.2.
5.1.2.2.2.3.1. Estimated pollution emission savings with respect to the Energy Rating Reference Home CO2 Index Reference Home shall be the difference between the pollution emissions of the Energy Rating Reference CO2 Index Reference Home Home and the pollution emissions of the Rated Home.
5.1.2.2.2.3.2. Estimated pollution emission savings with respect to the Typical Existing Home shall be determined in accordance with Sections 5.1.2.2.2.3.2.1 and 5.1.2.2.2.3.2.2.
5.1.2.2.2.3.2.1. For each fuel type, mMultiply the Energy Rating Reference Home pollution CO2 Index Reference Home emissions by 1.3 to determine the Typical Existing Home pollution emissions by fuel type.
5.1.2.2.2.3.2.2. Estimated pollution emission savings with respect to the Typical Existing Home shall be the difference between the pollution emissions of the Typical Existing Home and the pollution emissions of the Rated Home.
[1] (Informative Reference) http://www.epa.gov/cleanenergy/energy-resources/egrid/index.html
[2] (Informative Note) RESNET will compile and publish annual total output pollution emission rate data for NOx, SO2 and CO2 in accordance with the provisions of this section that can be used by Approved Software Rating Tools for the calculation of emissions.
[3] https://cambium.nrel.gov/
[4] Gagnon, Pieter, Will Frazier, Elaine Hale, and Wesley Cole, 2020. “Cambium Documentation: Version 2020.” Golden, CO: National Renewable Energy Laboratory. NREL/TP-6A20-78239. https://www.nrel.gov/docs/fy21osti/78239.pdf
Comment #8Page Number: 2Paragraph / Figure / Table / Note: section 6.1Comment Intent: ObjectionComment Type: TechnicalComment: Without the proposed language, the “null power” produced by onsite renewable systems would credit CO2 reduction attributes from OPP to the proposed CO2 Index while at the same time the CO2 reduction attributes will be claimed by another party that has purchased those same CO2 attributes, as occurs with most leased or third-party financed systems. This is the classic definition of double- counting. When the installer, leasing company or financial agent in the solar panel transaction strips environmental attributes from the homeowner by taking possession or transferring RECs, according to the Federal Trade Commission the power produced by the solar panels on the house would have an "unqualified claim" as renewable energy. And the US EPA has stated: “Electricity use from a renewable resource in the absence of owning the associated RECs is not considered renewable electricity (referred to as “null power”) and has the same environment profile as the residual grid electricity mix “. In all cases, without documented possession of RECs or other environmental attribute certificates for OPP the homeowner should not be able to claim CO2 reductions that would apply in the calculation of the CO2 Index. The RESNET Board approved the following resolution on October 2, 2018. The RESNET Board of Directors interprets its October 20, 2015, decision on the ownership of on-site power production systems as meaning that the ownership of onsite power production systems and their attributes shall not impact the asset rating or the HERS Index of the real property on which that on-site power production system is located. In furtherance of this interpretation and as implied by the original motion of the Executive Committee, the net on-site power production shall be considered nonpurchased energy for the purposes of the calculation of the HERS Index for the real property in question The proposed language in this comment does not address energy attributes for the HERS Index, or for the asset rating, but rather addresses only the carbon attributes for the proposed CO2 index in Addendum D-202x so it is consistent with Board policy. Proposed Change: 6.1 The CO2 emission factors for household combustion fuel use shall be those given in Table 5.1.2(1). 6.1.1 Annual hourly CO2 emissions from OPP in the CO2 Index Rated Home shall be calculated in accordance with Section 5.1.2.2.1 except when documentation is provided to the approved rating provider that renewable energy certificates or other energy attributes certification for OPP will be retained and retired by the owner
Without the proposed language, the “null power” produced by onsite renewable systems would credit CO2 reduction attributes from OPP to the proposed CO2 Index while at the same time the CO2 reduction attributes will be claimed by another party that has purchased those same CO2 attributes, as occurs with most leased or third-party financed systems. This is the classic definition of double- counting. When the installer, leasing company or financial agent in the solar panel transaction strips environmental attributes from the homeowner by taking possession or transferring RECs, according to the Federal Trade Commission the power produced by the solar panels on the house would have an "unqualified claim" as renewable energy. And the US EPA has stated: “Electricity use from a renewable resource in the absence of owning the associated RECs is not considered renewable electricity (referred to as “null power”) and has the same environment profile as the residual grid electricity mix “. In all cases, without documented possession of RECs or other environmental attribute certificates for OPP the homeowner should not be able to claim CO2 reductions that would apply in the calculation of the CO2 Index.
The RESNET Board approved the following resolution on October 2, 2018.
The RESNET Board of Directors interprets its October 20, 2015, decision on the ownership of on-site power production systems as meaning that the ownership of onsite power production systems and their attributes shall not impact the asset rating or the HERS Index of the real property on which that on-site power production system is located. In furtherance of this interpretation and as implied by the original motion of the Executive Committee, the net on-site power production shall be considered nonpurchased energy for the purposes of the calculation of the HERS Index for the real property in question
The proposed language in this comment does not address energy attributes for the HERS Index, or for the asset rating, but rather addresses only the carbon attributes for the proposed CO2 index in Addendum D-202x so it is consistent with Board policy.
6.1 The CO2 emission factors for household combustion fuel use shall be those given in Table 5.1.2(1).
6.1.1 Annual hourly CO2 emissions from OPP in the CO2 Index Rated Home shall be calculated in accordance with Section 5.1.2.2.1 except when documentation is provided to the approved rating provider that renewable energy certificates or other energy attributes certification for OPP will be retained and retired by the owner
Comment #9Page Number: 1Paragraph / Figure / Table / Note: Section 1Comment Intent: Not an ObjectionComment Type: EditorialComment: NBI is supportive of the introduction of a CO2 Rating Index to RESNET Standard 301 as we believe that residential buildings and dwelling units should be evaluated based on their energy and carbon emissions performance. We have provided several editorial changes to Section 1 to bring clarity and consistency that the scope of the standard includes both energy savings and carbon reductions. Going forward we hope that the RESNET 301 continues to revise the scope to ensure that significant carbon impacts throughout the building’s lifecycle, such as embodied carbon in building materials, can be comprehensively addressed by the Standard. Proposed Change: This standard identifies the metrics, tolerances, procedures, calculations and the required documentation to: (1) calculate the standard energy use of Dwelling Units and Sleeping Units, (2) determine the Energy Rating Index of Dwelling Units and Sleeping Units, (3) determine the CO2 Index of Dwelling Units and Sleeping Units, (4) define the minimum rated features of Dwelling Units and Sleeping Units, (5) calculate the retrofit energy savings and carbon reductions for existing Dwelling Units and Sleeping Units, (6) calculate the cost effectiveness of energy saving and carbon reductions improvements to Dwelling Units and Sleeping Units and (7) label the certified energy and carbon performance of Dwelling Units and Sleeping Units.
NBI is supportive of the introduction of a CO2 Rating Index to RESNET Standard 301 as we believe that residential buildings and dwelling units should be evaluated based on their energy and carbon emissions performance. We have provided several editorial changes to Section 1 to bring clarity and consistency that the scope of the standard includes both energy savings and carbon reductions. Going forward we hope that the RESNET 301 continues to revise the scope to ensure that significant carbon impacts throughout the building’s lifecycle, such as embodied carbon in building materials, can be comprehensively addressed by the Standard.
This standard identifies the metrics, tolerances, procedures, calculations and the required documentation to: (1) calculate the standard energy use of Dwelling Units and Sleeping Units, (2) determine the Energy Rating Index of Dwelling Units and Sleeping Units, (3) determine the CO2 Index of Dwelling Units and Sleeping Units, (4) define the minimum rated features of Dwelling Units and Sleeping Units, (5) calculate the retrofit energy savings and carbon reductions for existing Dwelling Units and Sleeping Units, (6) calculate the cost effectiveness of energy saving and carbon reductions improvements to Dwelling Units and Sleeping Units and (7) label the certified energy and carbon performance of Dwelling Units and Sleeping Units.