Committee forwards three R405 performance-path options to Council for CR102 review

The committee reviewed staff and PNNL work to align the simulated building performance option (R405) with the updated 2024 base-code stair-step sizing for residential buildings. Kevin Rose described three candidate approaches: a 10% improvement target, an 8% improvement target, or a more granular stair‑step approach with different percent improvements by 250‑square‑foot bands across the 11 home typologies. PNNL has not yet completed full R405 modeling for all prototypes, so staff proposed placeholder values for CR102 and offered to run final models during the CR102 comment period.

Committee members discussed prototype-size sensitivity and whether the 10% improvement is realized by smaller or larger homes. The committee voted to forward all three R405 options to the Council so the public and Council can assess and choose a path during CR102. Scott Bastiani moved the action and it carried by voice vote.

What it means: Forwarding multiple options preserves flexibility: Council members and public commenters can weigh tradeoffs among simplicity (single percent improvements) and precision (stair‑step values tied to home size). PNNL modeling later in the cycle could refine or replace placeholder values.