Pennsylvania Building Codes

Pennsylvania Uniform Construction Code (UCC) provides statewide building standards based on ICC model codes. As of January 1, 2026, Pennsylvania adopted the 2021 I-Codes with amendments approved by the UCC Review and Advisory Council. Administration: Over 90% of the state's 2,562 municipalities enforce UCC locally through municipal code officials or contracted third-party agencies. Municipalities that have opted out are served by PA L&I for commercial construction and certified third-party agencies for residential construction. Philadelphia (First Class City) has additional local code provisions and may adopt codes independently under Act 36 of 2017. Jurisdictions: 67 counties, approximately 2,562 municipalities (cities, boroughs, townships). Philadelphia is the only First Class City and is coterminous with Philadelphia County. Climate Zones: Zone 4A (southeastern PA: Philadelphia, Chester, Delaware, Montgomery, Bucks, York counties), Zone 5A (most of central and western PA - majority of state), Zone 6A (northern tier: Cameron, Clearfield, Elk, McKean, Potter, Susquehanna, Tioga, Wayne counties and portions of others). Statewide Special Requirements: - Ice Barrier: Required statewide per IRC R905.1.2 extending 24" inside exterior wall line - Residential Sprinkler Prohibition: Act 1 of 2011 repealed IRC R313.2 residential sprinkler requirement retroactive to January 1, 2010 - Mine Subsidence: Over 1 million homes in western/central PA at risk from abandoned coal/clay mines - Energy Code Alternative: PA Housing Research Center offers alternative energy compliance path Licensing: Building code officials must be certified by PA L&I in multiple categories (building inspector, electrical inspector, plumbing inspector, accessibility, etc.).