BL105 Fire Resistance — 2025 California Residential Code

California Residential Code (Title 24, Part 2.5) · 2025 edition · updated 2026-10-19 · 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 Residential Code (Title 24, Part 2.5) § BL105 · Effective January 1, 2026 · Official source: Building Standards Commission

BL105.1 Fire-resistance rating.¶

Hemp-lime walls do not have a fire-resistance rating. Fire-resistance ratings for hemp-lime wall assemblies shall be determined by testing in accordance with ASTM E119 or UL 263.

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BL105.2 Clearance to fireplaces and chimneys.¶

Hemp-lime surfaces adjacent to fireplaces or chimneys shall be finished with not less than ⅜ inch (10 mm) thick plaster of any type permitted by this appendix. Clearance from the face of such plaster to fireplaces and chimneys shall be maintained as required from fireplaces and chimneys to combustibles in Chapter 10, or as required by manufacturer’s instructions, whichever is more restrictive.

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▸Contents — California Residential Code (Title 24, Part 2.5)

California Residential Code (Title 24, Part 2.5)

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