Building Code Council advances structural, elevator and fire‑separation provisions for multiplex housing

The Building Code Council’s multiplex housing tag approved a set of safety and design provisions during its Nov. 18 meeting, moving the draft appendix closer to the full council’s review.

Roger Goringa, chairing the session, said the group had worked toward simplifying definitions and ensuring the draft aligns with the IRC. In three voice votes taken during the meeting, members approved (1) a package of structural provisions for three‑story multiplex housing, (2) section 1.0.6 addressing elevator standards and how residential conveyances are handled, and (3) text directing users to IRC Table R302.1(1) for fire‑separation distances in multiplex buildings.

Why it matters: The votes affect how local building officials and designers will apply the residential code for up to three‑story multiplex buildings, including whether prescriptive lateral (brace panel) methods are permitted, what elevator standards builders must meet, and the distances and fire‑rated construction required between buildings.

What was decided and why - Structural provisions: After reviewing a basis-of-lateral-force memo and consulting practicing engineers, the tag voted to accept modified structural language that allows IRC prescriptive lateral design in most seismic areas but clarifies that seismic design category D2 requires an engineered design by a registered design professional. Michael moved to accept the structural provisions; Jeremy seconded. The motion carried by voice with one recorded nay.

- Elevator standards (section 1.0.6): Members debated whether to require stretcher‑sized (gurney) cars or to permit smaller LULA (limited‑use/limited‑application) and private residence elevators. Gerald Brown, chief elevator inspector for Washington, told the group that local building officials already have a process to approve smaller conveyances via a building‑official form and emphasized rescue and stretcher access considerations. The tag concluded it will not require stretcher‑sized cars for multiplexes and approved proposed elevator language that defers to IRC provisions for passenger and LULA conveyances while excluding private‑residence elevators from required standards. A voice vote approved the section; no roll‑call tally was recorded.

- Fire separation distances: Fire officials urged caution about close lot lines and reliance on NFPA 13R sprinkler systems, which do not provide exterior coverage. After debate, the tag directed staff to reference IRC Table R302.1(1) (the IRC’s more conservative residential table) for fire‑separation distances for multiplex buildings. The motion was approved by voice vote.

What wasn’t decided: The tag discussed but did not finalize EV‑charging percentages and the precise wording for several fire and egress cross‑references; staff (Dustin) was asked to post revised markups for review before the next meeting.

Votes and process notes: All votes reported in the session were voice votes; the transcript and meeting record do not provide a full roll‑call tally of yes/no/abstain for each motion. Where the tag changed or accepted language, staff were directed to update the baseline appendix and post the edited drafts for stakeholder review.

Next steps: Staff will post the updated text and diagrams for public comment and the tag will revisit outstanding EV, egress, and final wording at the next scheduled meeting.