Gutter cleaning, repair and new gutters in San Francisco, CA

Gutter and downspout size for San Francisco rain

What overwhelms a gutter is a burst, not a season. In San Francisco the five-minute rain expected about once in ten years falls at 2.95 inches an hour (NOAA Atlas 14 Volume 6). At that rate one 2-by-3-inch downspout drains about 2,440 square feet of roof and one 3-by-4-inch downspout about 4,880, by the rule in the Copper Development Association’s design handbook. Try your own roof in the gutter and downspout calculator, which starts from this figure.

The houses in San Francisco

Half the homes in San Francisco were built by 1945, 77% before 1980 (ACS 2020–2024). In a neighborhood that age, many houses are on their second set of gutters or due for one, and the fascia board behind them is worth checking at the same visit. On a house built before 1978, replacing more than 20 square feet of painted fascia or trim falls under the EPA’s lead-safe rule, so ask whether the crew is certified.

38% of households own their home, and 18% of homes are detached houses, 12% townhouses. In a townhouse or HOA community, check who owns the gutters and what colors are allowed before booking.

Hiring in California

Ask any contractor working in San Francisco what California requires of them for gutter work, and to show proof of insurance. Hiring a gutter contractor

In California’s fire hazard severity zones, the 2025 Wildland-Urban Interface Code (in force January 1, 2026) requires gutters and downspouts of noncombustible material, and gutters fitted with an approved means to keep leaves and debris from collecting (section 504.4). (2025 California Wildland-Urban Interface Code, Chapter 5 (UpCodes))