California Building Standards

What are Building Codes and Why are they Important?

Building regulation in the United States began in the late 1800s when large cities began enforcing standards in response to large fires in densely populated urban areas, including the great Chicago fire of 1871. The primary intent of early building codes was to reduce fire risk but over time, their scope has broadened. The City of Riverside adopted its first building code ordinance on July 28, 1915, twelve years before the first national code was enacted and known as the 1927 Uniform Building Code.

Today, building codes are a set of minimum standards that address a variety of construction disciplines including, but not limited to: structural integrity, fire resistance, exiting, lighting, sanitation and ventilation, accessibility, sustainability and construction materials. They specify the minimum requirements necessary to safeguard the health, safety and welfare of building occupants.

Though you have little control over the occurrence of hazards in the built environment, establishing mitigation measures that include the latest building codes is one of the best ways we can help protect our communities from the hazards we face. Building codes increase occupant safety during a disaster, protect and preserve the local economic base, help ensure the continuity of essential services and support more rapid recovery from disasters.

Adopted Codes and Standards

The latest version of California Code of Regulations, Title 24, the California Building Standards Code was adopted by the City of Riverside and became effective on January 1, 2026. Title 24 includes twelve parts:

2025 California Building Code

2025 California Residential Code

2025 California Fire Code

2025 California Existing Building Code

2025 California Wildland-Urban Interface Code

2025 California Historical Building Code

20225 California Electrical Code

2025 California Plumbing Code

2025 California Mechanical Code

2025 California Green Building Standards Code (CAL Green)

2025 California Energy Code

2025 California Administrative Code