This session outlines the significant changes introduced in the 2025 editions of the
National Model Codes—the National Building Code (NBC), National Fire Code (NFC), National Plumbing Code (NPC), and National Energy Code for Buildings (NECB). Key changes include new provisions for large farm buildings, expanded requirements for encapsulated mass timber construction, and updated design approaches for wind, snow, and seismic loads. The session will also cover new accessibility provisions for adaptable and visitable dwelling units, revised requirements for radon mitigation, energy performance, and new requirements for operational greenhouse gas emissions, as well as updates to climatic data to reflect projected future conditions.
In addition, changes affecting plumbing systems, drainage, and potable water protection will be highlighted, along with updates to thermal bridging calculations, lighting, and energy modelling requirements in the NECB. The session will also address the new Parts dealing with the alteration of existing buildings introduced in both the NBC and NECB.