Roof Doctor | Roofing Services in San Francisco, CA 94115

In San Francisco, simply removing the moss isn't enough due to our persistent moisture. We recommend a professional cleaning to remove the moss, followed by an application of zinc or copper strips along the roof ridge. These strips release ions with each rain, creating a long-term barrier against regrowth, which is crucial for preventing moisture retention and wood rot common here.

Even light precipitation in SF can expose failing seals. Skylight leaks here are often due to degraded flashing or sealant around the unit, which breaks down over time from UV exposure and temperature fluctuations. A proper repair involves removing the old material, inspecting the underlying structure for water damage, and installing new, high-grade flashing and sealants designed for our coastal microclimates.

We advise a professional inspection at least once a year, ideally before the rainy season. Given our specific issues with moss and micro-leaks, more frequent visual checks by homeowners are wise. Look for dark streaks (algae), piled moss in valleys, or any moisture stains on interior ceilings near skylights, and call a pro if you spot them.