Board restores Appendix RM and reinstates debiasing in R405 table

The Low Energy and Carbon Code Board on a pair of votes this meeting decided to (1) restore Appendix RM — the cost-based energy compliance appendix — without the debiased R405 table, and (2) reinstate the debiasing elements in the R405 site-energy table used for the simulated building-performance path.

Board members said the two actions were related but distinct: restoring Appendix RM gives local jurisdictions the option to use an energy-cost-based pathway, while the R405 vote restored the “debiasing” baseline adjustments in the site-energy tables used for whole-building modeling.

Dan (board member) presented the Appendix RM motion, saying the change “was coming from builders in our jurisdiction and, basically, wanting to allow the local jurisdictions to select which method is best suited.” Elizabeth (board member) said she had supported Appendix RM previously and that “it would actually serve more electrified projects better.” Carolyn (board member) pressed the board to ensure the appendix language compares like fuels — electric to electric and gas to gas — so the appendix would not reintroduce bias depending on which baseline table the board adopts for R405.

Board members discussed technical interactions between R405 (site energy) and Appendix RM (energy cost). Staff explained that Appendix RM as originally written references the R405 table; if the board adopts a debiased R405 for the site-energy approach, RM will reference that table unless the RM language is explicitly modified. To address that possibility, members asked the proposer to clarify the Appendix RM language so the appendix would compare like-to-like fuels regardless of which R405 table the board finalizes.

Votes and outcome: restoring Appendix RM without the debiased R405 table passed by raised hands (14 yes, 3 no, 0 abstain). Separately, the board voted to reinstate the debiasing elements in the R405 table (15 yes, 3 no, 0 abstain). Board members said they would return to editorial language to ensure the appendix and R405 cross‑references make explicit whether the comparison is fuel-specific or debiased, depending on which baseline the board adopts.

Why it matters: the decisions affect what modeling baseline jurisdictions can adopt and how electric versus gas systems are compared. Restoring Appendix RM gives jurisdictions a cost-based compliance option; reinstating R405 debiasing changes the default simulated building baseline and may influence whether electrified solutions or gas systems appear more favorable under the site-energy modeling path.

Next steps: staff will edit the Appendix RM language to make explicit which R405 table it references (and whether it compares like fuels), and the board will consider that clarified language in later finalization work.