The Ohio Residential Code – 2019 is based on the 2018 International Residential Code (IRC) and became effective on July 1, 2019. It sets the minimum standards for the design, construction, alteration, repair, and maintenance of one‑, two‑, and three‑family dwellings and townhouses in Ohio, with the goal of protecting public health, safety, and general welfare. The Code covers structural strength and stability, sanitation, light and ventilation, energy conservation, and fire and other hazard safety. It incorporates Ohio‑specific amendments to reflect local conditions, practices and administrative procedures. The Code is enforced through certified local building departments or the state when needed, and it provides a consistent regulatory framework for residential construction across Ohio.