Missouri Building Codes

Missouri has NO mandatory statewide building code. Local jurisdictions independently adopt codes - varies widely from IRC 2006 to IRC 2021. When no local code adopted, 20 CSR 2030-2.040 requires design professionals use IBC 2018 as evaluation criteria. NO mandatory statewide energy code - local adoption only (Class III counties cannot adopt). State Fire Marshal enforces fire codes for state-owned buildings. Division of Fire Safety handles fire prevention. 114 counties plus St. Louis (independent city). Climate zones 4A (most) and 5A (northern border). Major cities: Kansas City (IBC/IRC 2018), St. Louis City (BOCA-based legacy codes transitioning), Springfield (2015 codes), Columbia (2018 codes). Legislative efforts ongoing (SB743/HB2870 Missouri Building Codes Act). CRITICAL: Always verify current code adoption with local jurisdiction before starting work - no statewide uniformity.