307 Smoke Alarms — 2025 California Existing Building Code

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

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Cite as: 2025 California Existing Building Code (Title 24, Part 10) § 307 · Effective January 1, 2026 · Official source: Building Standards Commission

307.1 Smoke alarms.¶

Where an alteration, addition, change of occupancy or relocation of a building is made to an existing building or structure of a Group R and I-1 occupancy, the existing building shall be provided with smoke alarms in accordance with the California Fire Code or Section R310 of the California Residential Code .

Exception: Work classified as Level 1 Alterations in accordance with Chapter 7.

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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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