The IRC Tag reviewed Washington’s amended prescriptive tables for exterior decks (footings, joists, beam spans and post heights) and kept them generally as staff presented while flagging potential follow‑through work tied to ongoing snow‑load mapping changes.

Why it matters: deck prescriptive tables are commonly used by homeowners, builders and permitting staff to size footings, joists and posts without engineering. Changes to snow-load mapping or to slenderness limits for posts could change the recommended allowable spans and heights in these tables and affect safety and retrofit costs.

Josh Mergans (tag member) and Dustin (staff member) discussed that the IRC currently refers to allowable‑stress‑design (ASD) ground‑snow loads in some tables and that proposed revisions to snow-load inputs could ripple through the deck tables. Jen (tag member) noted that the technical committee that prepares the deck tip sheet recommended limiting 4x4 posts to a 10‑foot height for slenderness concerns; staff and tag members agreed this recommendation merits calculation and could require a proposal if adopted. The tag agreed to keep the current Washington deck tables in place for now, add a notation to monitor snow‑load amendments, and asked Josh to run structural checks and present any proposed changes (for example a 4x4 height reduction) with supporting calculations.

The tag did not change the published tables at the meeting; staff will follow up with calcs and, if needed, a proposal for the formal rulemaking process.