Berkeley's spark arrestor rule and your new chimney cap
Berkeley adopted the 2025 California Wildland-Urban Interface Code as Berkeley Municipal Code Chapter 19.49. Under that chapter, chimneys serving fireplaces that burn solid or liquid fuel must have a spark arrestor made of 12-gauge woven or welded wire screen with openings no larger than 1/2 inch. The rule applies in Berkeley's High and Very High Fire Hazard Severity Zones, including the Panoramic and Grizzly Peak mitigation areas. (Source: City of Berkeley, Ordinance 7,991-N.S., Council item 41, Dec 2, 2025, second reading, ordinance attachment.)
- Which chimneys: those serving fireplaces that burn solid or liquid fuel, such as a wood-burning fireplace.
- Where: Berkeley's High and Very High Fire Hazard Severity Zones, including the Panoramic and Grizzly Peak mitigation areas.
- What the screen must be: 12-gauge woven or welded wire, with openings no larger than 1/2 inch.
What the rule changes about installing a cap
Most chimney caps have a mesh screen around the sides, but caps are sold with many wire gauges and opening sizes. If your home is in one of the covered zones and your fireplace burns wood or another solid or liquid fuel, the screen is the part that matters for the rule. We check the screen's wire gauge and opening size against the code's numbers before the cap goes on, so you aren't left with a cap that fits the flue but falls short on the screen.
The City is the authority on whether a specific address sits inside a High or Very High Fire Hazard Severity Zone. If you're unsure, confirm your zone status with the City of Berkeley before the work is scheduled.
Helpful to know before your estimate
- Whether your home is in a High or Very High Fire Hazard Severity Zone
- What your fireplace burns: wood, another solid or liquid fuel, or gas
- Whether there is a cap on the chimney now, and whether it is loose, rusted or missing its screen
- How many flues come out of the top of the chimney
Cap, cap replacement or a separate spark arrestor
If the chimney has never had a cap, a new cap with a compliant screen covers the flue and the spark arrestor requirement in one installation. If a cap is already there but its mesh is damaged, the wrong size or missing, chimney cap replacement or a separate chimney spark arrestor installation may suit you better. We also install chimney animal screens when keeping birds and animals out is the main concern. Whichever option fits, the estimate explains why.
What affects chimney cap installation in Berkeley
- Berkeley's Wildland-Urban Interface Code (BMC Chapter 19.49) requires chimneys serving fireplaces that burn solid or liquid fuel to have a spark arrestor of 12-gauge woven or welded wire screen with openings no larger than 1/2 inch; it applies in Berkeley's High and Very High Fire Hazard Severity Zones, including the Panoramic and Grizzly Peak mitigation areas. Source: City of Berkeley - Ordinance 7,991-N.S. adopting the 2025 California Wildland-Urban Interface Code as BMC Chapter 19.49 (Council item 41, Dec 2, 2025, second reading, ordinance attachment).
Chimney cap installation in brief
The job covers measuring the flue and the top of the chimney, choosing a cap that fits both the chimney and the fuel your fireplace burns, and fastening it securely. A capped flue keeps out rain, leaves, birds and small animals, and the screen catches embers before they leave the chimney. While we're on the roof, we look at the crown and the masonry, so any damage gets flagged before the cap goes on. For cap styles and each step of the visit, read how chimney cap installation works.
When a different job comes first
A cap only works on a sound chimney top. If the crown is cracked, mortar is crumbling or water is already getting in, chimney repair in Berkeley may need to come before or alongside the cap. If smoke smells, debris or nesting suggest the flue itself needs attention, chimney sweeping or animal and nest removal usually comes before a new cap is fitted. Still deciding whether a cap is worth it at all? Start with do you need a chimney cap.
Booking a cap installation
Same-day visits are available where the schedule allows, so it's worth asking when you call. Our full chimney cap installation service covers wood-burning and gas fireplaces, and we work on all major brands. To see everything else we handle for homes in Berkeley, including commercial and property-manager work, request an estimate or get in touch.
Free estimates.
Tell us what your fireplace burns and whether your home is in a fire hazard zone, and we'll recommend a cap and screen that fit your chimney.
Sources (1)
The sources of the Berkeley facts on this page.
- 1City of Berkeley - Ordinance 7,991-N.S. adopting the 2025 California Wildland-Urban Interface Code as BMC Chapter 19.49 (Council item 41, Dec 2, 2025, second reading, ordinance attachment)
