Earlier editions: 2022 2019

604 Alteration—level 3 — 2025 California Existing Building Code

California Existing Building Code (Title 24, Part 10) · 2025 edition · updated 2026-09-25 · California

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Italicized text is a California amendment to the model code, as printed in the official publication.

Cite as: 2025 California Existing Building Code (Title 24, Part 10) § 604 · Effective January 1, 2026 · Official source: Building Standards Commission

604.1 Scope.¶

Level 3 alterations apply where the work area exceeds 50 percent of the building area.

Exceptions & meaning →

604.2 Application.¶

Level 3 alterations shall comply with the provisions of Chapters 7 and 8 for Level 1 and 2 alterations, respectively, as well as the provisions of Chapter 9.

Exceptions & meaning →

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▸Contents — California Existing Building Code (Title 24, Part 10)

California Existing Building Code (Title 24, Part 10)

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