What can I check from inside?
- Brown rings on top-floor ceilings, especially near exterior walls under a parapet.
- Damp or peeling paint where a bay window meets the main wall.
- Musty smells in a top-floor closet or attic hatch after rain.
What can I see from the sidewalk or a neighbor's window?
From the street you may see sagging gutters, cracked parapet caps or missing shingles on a steep front. If a neighbor's upper window overlooks your flat roof, look for dark pools, bubbles in the membrane, or grass and debris collecting at the drain.
Which signs are specific to San Francisco homes?
San Francisco roofers most often find blistered or split flat-roof membranes, failed parapet and scupper flashing, ponding at clogged drains, and leaks where Victorian bays and cornices meet the main roof. On older homes, they also find several past layers that must come off before a new roof goes on.
When is it time to call a roofer?
Call when a stain grows after each storm, water stands on the roof more than two days after rain, or a repair from last winter is leaking again. Don't walk on an old flat roof yourself; soft decking can give way.
Every roofer we work with is licensed, insured and highly reviewed by Bay Area homeowners.
Get a free replacement quoteFrequently asked questions
Is ponding on a flat roof normal?
Small puddles that dry within a day or two can be normal. Water that stays longer stresses seams and usually points to drain or slope problems.
Why does my ceiling leak only in wind-driven rain?
Wind pushes water sideways under parapet caps, window flashing and siding joints. It's a flashing problem first, not always the field of the roof.
Can I see my roof without climbing up?
Often from a neighbor's upper window or with a roofer's photos and drone shots.
Sources
Sources reviewed November 11, 2026. Figures are published estimates and official fees, not quotes. Confirm prices, permits and requirements with your contractor and building department. This page is general information, not legal or insurance advice.