The following comments have been submitted:
Comment #1Page Number: 4Comment Intent: ObjectionComment Type: TechnicalComment: The intent of the IAF for rated homes is to "establish an index adjustment factor methodology that adjusts the rating index for size and configuration in order that similarly configured and equipped dwellings of different sizes and configurations will achieve an equivalent energy rating index." A consequence of the equations created to calculate this IAF, intended or unintended, is that existing homes or apartment dwellings that have poor envelopes and mechanical equipment resulting in 100+ HERS Indices are penalized with negative IADsave values which in turn creates an IAF that is below 1, functionally increasing the HERS Index. Was this this intent? If so, it is not clear based on the RESNET e-mails that have come out attempting to justify the introduction of this factor, nor was not clear in the RESNET-sponsored webinar on the subject. The technical change/exception that I would like to see added to the proposed amendment should explain that for all dwelling units with a HERS Index above 100, the IADsave will equal 0 and therefor the IAF=1. Proposed Change: x.x.3 The saving represented by the IAD shall be calculated using equation x.x.3-1. IADSAVE = (100 – ERIIAD) / 100 (Eq. x.x.3-1) Exception: Where ERIIAD>100, IADSAVE=0.
The intent of the IAF for rated homes is to "establish an index adjustment factor methodology that adjusts the rating index for size and configuration in order that similarly configured and equipped dwellings of different sizes and configurations will achieve an equivalent energy rating index." A consequence of the equations created to calculate this IAF, intended or unintended, is that existing homes or apartment dwellings that have poor envelopes and mechanical equipment resulting in 100+ HERS Indices are penalized with negative IADsave values which in turn creates an IAF that is below 1, functionally increasing the HERS Index. Was this this intent? If so, it is not clear based on the RESNET e-mails that have come out attempting to justify the introduction of this factor, nor was not clear in the RESNET-sponsored webinar on the subject.
The technical change/exception that I would like to see added to the proposed amendment should explain that for all dwelling units with a HERS Index above 100, the IADsave will equal 0 and therefor the IAF=1.
Comment #2Page Number: 3Comment Intent: ObjectionComment Type: TechnicalComment: Specify whether the "Balanced Whole-House Ventilation System" specified under "Whole-House Mechanical Ventilation" in Table x.x.1(1) has energy recovery or not. If it does, specify the sensible and total efficiencies of the system. Proposed Change: Balanced Whole-House Ventilation System without energy recover and with fan power = 0.70 * fanCFM * 8.76 kWh/y
Specify whether the "Balanced Whole-House Ventilation System" specified under "Whole-House Mechanical Ventilation" in Table x.x.1(1) has energy recovery or not. If it does, specify the sensible and total efficiencies of the system.
Balanced Whole-House Ventilation System without energy recover and with fan power = 0.70 * fanCFM * 8.76 kWh/y