Flashing, Chimney & Skylight Repair in San Francisco

When you need Flashing, Chimney & Skylight Repair in San Francisco, the leak almost never starts where the water shows up. It starts at a chimney cricket, a skylight curb, a parapet cap, or the seam where a false front meets a flat roof in Pacific Heights or Noe Valley. We have been bending and installing sheet metal on this city's roofs since 2009, and we fabricate flashing in-house so the fit is exact instead of close enough. San Francisco gives a roof more chances to leak than most cities: steep hills, wind-driven rain off the Pacific, and rows of Victorian and Edwardian homes where the original flashing has been patched four or five times. If water is staining a ceiling or you can see rust trails on the metal, start with our metal roof leak repair page and then call (628) 356-4308 for a look at the actual penetration.

Why flashing and chimney work is the number one leak source on San Francisco roofs

Walk any block in the Mission, the Haight, or Bernal Heights and you will see the same pattern: a roof surface that is still sound, surrounded by penetrations that are not. Chimneys on 1880s and 1900s homes were often flashed with tar and a thin apron that has cracked and pulled away from the masonry. Skylights added in the 1970s and 1980s sit on curbs built from dry rot. Parapets and false fronts on flat-roof row houses in the Sunset and Richmond collect water behind the cap and push it back under the roofing. The bay windows and ornate cornices common here hide the first signs until the damage is inside the wall.

• Chimney flashing fails first because masonry and metal move at different rates through wet winters and dry summers.
• Skylight curbs rot from the bottom up when the original installer relied on sealant instead of a proper pan and counterflashing.
• Parapet and false-front caps on flat roofs in the Sunset and Richmond trap water that then runs backward under the membrane.
• Valley flashing on steep Victorian roofs clogs with cypress and eucalyptus debris and rusts through where water stands.

Every one of those failures is repairable with bent metal, and none of them are fixed by another tube of roof cement.

Key info: On a 1908 Edwardian in Noe Valley, the ceiling stain tracked back to a chimney that had been flashed with mastic three times. The mastic hid the gap but never closed it. A new copper apron and counterflashing, bent on site to the chimney's actual dimensions, stopped the leak for good.

San Francisco roofing permits and inspection requirements vary by jurisdiction and by scope, so we always confirm the rules with the local building department before work starts. You can review the city's permit process at sf.gov permits.

How we trace and repair a flashing leak on a San Francisco roof

We do not guess at the leak location from the ground. We get on the roof, open the area around the penetration, and find where water is actually entering. On hillside homes stepping up Twin Peaks or Diamond Heights, that also means checking the uphill side of every penetration, because water runs along the roof and pools where the slope changes. Then we fabricate the replacement piece from flat sheet stock and fit it to the real dimensions of the chimney, curb, or wall.

1. We inspect the penetration and the surrounding roofing to find the entry point, not just the stain.
2. We measure the chimney, skylight curb, parapet, or valley and cut the flashing pattern in the shop or on the tailgate.
3. We remove the failed flashing, old sealant, and any rotted curb or sheathing underneath.
4. We install the new pan, apron, step flashing, or counterflashing with the correct laps and fasteners.
5. We seal the terminations with compatible sealant and test the repair with a controlled water check.

The repair is only as good as what it sits on, so we replace rotten curb framing and sheathing before we cover it.

Key info: A Spanish Revival home in the Marina had a skylight leaking into a hallway. The curb framing was pine that had been wet for years. We rebuilt the curb, bent a new pan and counterflashing, and tied it into the surrounding tile. Patching the old curb would have bought one more winter at most.

If your home is in the 94102 ZIP or nearby, see our flashing and skylight repair service in San Francisco 94102 for local details.

Repair approaches we use around chimneys, skylights, and parapets

Not every penetration calls for the same metal or the same method. A chimney on a steep Victorian roof needs step flashing and counterflashing. A skylight on a low-slope roof in the Sunset needs a soldered or sealed pan with a raised curb. A parapet cap needs a slope and a drip edge so water leaves the wall instead of running down it. We match the approach to the roof, the climate exposure, and the material already on the house.

Flashing, Chimney & Skylight Repair cost in San Francisco: what to expect

Most flashing repairs start around $600 and go up from there. That starting figure covers a straightforward repair on an accessible penetration: a small chimney apron, a skylight reseal with new metal, or a short section of valley flashing. The price climbs when the job needs more material, more access, or more tear-out. A chimney on a steep Victorian roof in Pacific Heights takes longer to reach and protect than a flat-roof penetration in the Sunset.

• The type of penetration matters, since a full chimney reflash costs more than a single skylight curb.
• Access drives labor, especially on steep hillside homes in Bernal Heights and Diamond Heights.
• Hidden rot under the flashing adds carpentry to the metal work.
• Copper and specialty metals cost more in material than galvanized or painted steel.
• Storm timing can affect scheduling, because demand spikes after atmospheric-river storms.

Get two or three estimates so you can compare scope, not just the number. A quote that skips the rot repair is not the same job as one that includes it. Our full pricing overview breaks down typical ranges by repair type.

Flashing, Chimney & Skylight Repair near me: how to vet a contractor near San Francisco

Hiring for this work is mostly about verifying three things: license, insurance, and whether the contractor actually fabricates metal or just buys stock pieces and seals the gaps. Ask for the license number and verify it with the state, and ask for a certificate of insurance before anyone gets on your roof. On historic homes and in HOA-governed buildings, confirm that the flashing material and profile will pass design review before the work is ordered.

• Confirm the contractor is licensed and carries both liability and workers' compensation insurance.
• Get at least two or three written estimates that describe the scope in detail.
• Ask for references from jobs in San Francisco with similar roofs and penetrations.
• Ask who pulls the permit and whether the local building department requires an inspection for your scope.
• Check HOA or historic district rules on visible metal color and profile before work begins.

A contractor who cannot explain how the flashing will be attached, and to what, is not the one to hire. Reach us through our contact and free estimate page when you are ready to compare.

Flashing is the smallest square footage on your roof and the source of most of its leaks. We are a Metal Roofing Alliance member and have been bending and installing metal on San Francisco roofs since 2009. Call (628) 356-4308 to schedule an inspection of the chimney, skylight, or parapet that is giving you trouble.

Flashing, Chimney & Skylight Repair in San Francisco: Pricing Guide

Indicative pricing, the exact cost depends on square footage, finish, and site access. Free personalized estimate within 24h at (628) 356-4308.