Seeking some clarification around Lighting Power Allowances for 90.1-2016/2019/2022 Appendix G/PRM. This is specific to the “Additional Interior Lighting Power” allowances permitted in Section 9.6.
Per the 2016 and 2019 versions the values from Table G3.7, the “Additional Interior Lighting Power” allowances are not addressed. Only the general allowances for ‘Sales Floor’ or ‘Retail Facilities’ are in the tables. The PNNL guide for the 2016 version includes the “Additional Lighting Power: Retail Display Lighting Power” allowances on Page 3.40. And these allowances align to 90.1-2004 requirements which ‘new G’ is based upon; Retail 1,2,3 = 1.6W/sf; Retail 4 = 3.9 W/sf. However, this is the PNNL guide and NOT the code or ASHARE User Manual - but it is correct.
Checking the 2022 version, the allowances are not noted in either Table G3.7-1 or G3.7-2; but in the Table G3.1>Part 6>Baseline Building> it states “…the Baseline building design retail display lighting additional power shall be equal to the limits established by Section 9.5.2.2.(b) or same as proposed, which ever is less.” Section 9.5.2.2 points to Table 9.5.2.2 for these values. Retail 1,2=0.4W/sf; Retail 3=0.70 W/sf; Retail 4=1.0 W/sf. This is (wildly) not inline with the 2004 Standard. It removes what should be an advantage by having ‘which ever is less’ and is an extremely low value given the BPFs for retail are in the 0.51-0.41 range.
So – how have others handled the omission of these allowances in the 2016 and 2019 code? Completely ignoring the allowance (severely) limits a proposed design. Treating these the same for proposed to baseline also limits the design to newer code allowances when the compliance threshold is based upon a much older code. Have AHJ’s accepted the PNNL Guidance?