MO SB1431

Establishes the "Missouri Building Codes Act" creating statewide building codes covering building, electrical, energy, fire, mechanical, plumbing, residential, and fuel/gas standards, with implementation required by August 28, 2028

Creates the Missouri Building Codes Commission within the Department of Commerce and Insurance, consisting of the state fire marshal, nine governor-appointed industry professionals, and a state codes manager to oversee code development and maintenance

Requires jurisdictions with existing building codes to adopt the Missouri building codes by August 28, 2026; jurisdictions in third or fourth classification counties without codes may adopt them only after voter approval via ballot measure

Allows local amendments to state codes only with commission approval, requiring justification based on safety, health, local conditions, and housing affordability, with a 60-day review period

Exempts agricultural buildings from all Missouri building codes and creates a Missouri Building Codes Fund funded by permit fees (up to $7 per permit, adjusted for inflation) to support inspector training, code books, and commission operations