Every month we round up state building-code adoption activity — what changed, what's about to change, and what it means if you design, build, or inspect in that state. Here's the August 2026 edition.
The headline moves
New Hampshire is mid-transition to the 2024 I-Codes. The state building code update covers the 2024 IBC, IRC, IEBC, IMC, IPC and ISPSC (with the IECC held at 2018 and the NEC at 2023), and permits filed during the second half of 2026 may follow either the 2021 or 2024 editions during the transition window running July 1 through December 31, 2026. From January 2027, it's the 2024 editions. If you're pulling NH permits this fall, declare your edition up front — plan reviewers will ask.
Washington is voting on the 2024 codes now. The State Building Code Council filed its CR-102s this spring: comment on the IBC/IRC/IMC/IFC/UPC package closed in June with final adoption targeted for August 28, 2026, and the commercial and residential energy codes are in hearings this month with adoption targeted for September 25, 2026. The effective date for the whole 2024 package is May 3, 2027 — so Washington projects have a long runway, but the amendment language is being finalized right now.
Oregon has an NEC 2026 date. Oregon adopted the 2026 National Electrical Code with an effective date of October 1, 2026 — one of the first states to move to the brand-new edition. Electricians working across the Washington–Oregon–Idaho corridor now face three different NEC editions depending on the state line.
The national picture
- NEC: roughly 35 states enforce the 2023 NEC as of mid-2026, with recent effective dates including New York (Dec 31, 2025), Rhode Island (Dec 1, 2025), and California and Delaware (Jan 1, 2026). Seven states — Colorado, Idaho, Massachusetts, New Hampshire, Utah, Vermont and Washington — have already moved to (or formally adopted) the 2026 NEC.
- 2024 IBC/IRC: adoption is rolling through 2025–2026, state by state. New Hampshire is in its transition window now; Washington votes this month with a 2027 effective date; North Carolina's 2026 code update is in progress. Most other states remain on the 2021 or 2018 editions.
What to do with this
- Check your state's page — every BuildSpec state page lists the adopted editions we track, and the address report resolves the exact editions and amendments for a project location.
- Bidding across a state line? Edition differences change real numbers (the 2021→2024 IRC and 2023→2026 NEC both moved requirements that show up in bids). Confirm the edition before you price.
- Transition windows are opportunities — where either edition is allowed (like NH through December), you can often choose the edition that favors your design. Ask the building department which they prefer to review.
Sources
- New Hampshire Building Officials Association — State Building Code Change 2026
- Washington State Building Code Council
- ElectricalToolbox — NEC Adoption by State
This tracker is compiled from official state sources and adoption trackers. Always confirm the enforced edition with the local building department — adoption dates shift, and local amendments apply. Next edition: September 2026.