Oregon Building Codes

Oregon operates under a unique statewide mandatory building code system established in 1973 (Senate Bill 73). The Building Codes Division (BCD) within DCBS adopts, amends, and interprets 11 specialty codes comprising the Oregon State Building Code. All 36 counties must enforce state codes; municipalities may assume building inspection programs or defer to county/state administration. Per ORS 455.040, the state building code is applicable and uniform throughout Oregon, and no municipality may enact different requirements without Director authorization. Oregon is a Dillon Rule state for building codes. Current codes: 2023 ORSC (IRC 2021 base) mandatory April 1, 2024; 2025 OSSC (IBC 2024 base) mandatory April 1, 2026; 2025 OEESC (ASHRAE 90.1-2022) mandatory July 1, 2025; 2023 OESC (NEC 2023) and 2023 OPSC (UPC 2021). Oregon has two IECC climate zones: 4C (Marine, western Oregon - 18 counties) and 5B (Cold-Dry, eastern Oregon - 18 counties). The state faces significant Cascadia Subduction Zone seismic risk statewide, with tsunami hazard in coastal counties and wildfire risk in designated zones. Wildfire Hazard Mitigation standards (ORSC R327) are available for local adoption per ORS 455.433. Oregon does not require residential fire sprinklers statewide but requires ice barrier protection where average January temperatures ≤25°F (primarily eastern Oregon Zone 5B). Water heater seismic strapping required statewide per OPSC 507.2. Building code enforcement is delegated to local building departments, with BCD providing permit services in jurisdictions without local programs via ePermitting system (https://aca-oregon.accela.com/oregon/). New code editions typically have 6-month phase-in period during which either previous or new code may be used. Re-roofing requires building permit per ORSC R105.2.