Commercial Roofing: Costs, Lifespan and Alternatives

A full replacement in Mission District is permitted and inspected through the San Francisco Department of Building Inspection. Small repairs generally are not, but the layer count and assembly are checked on any permitted job.

We start at the flashings, check the deck from inside the attic, and photograph every elevation. On a Mission District property we pay particular attention to dried-out underlayment and attic temperature.

Two visits a year: clear valleys and gutters before the rains, then check flashings after the first real storm. In Mission District that matters most because asphalt dries out and sealant pulls back from penetrations years before the field wears through.

One to three days on a typical Mission District property, depending on size, pitch and how much deck needs replacing. Nothing is left open overnight.

Size, pitch, layer count and deck condition drive the number on any Mission District roof. The line that moves is deck repair, so it belongs in the Mission District quote at a rate per sheet rather than as an allowance.

Check the licence, liability cover and workers' compensation, then ask any Mission District contractor what happens if the deck is worse than expected — and get that answer in writing before the covering comes off.

Yes. Low-slope sections on Mission District buildings need a membrane or coating system rather than shingle laid flatter than it is rated for, and they are quoted separately from the pitched roof.

Mission District sits in San Francisco County and takes long dry heat, hard thermal cycling and rain that arrives in a few concentrated storms. In practice that means asphalt dries out and sealant pulls back from penetrations years before the field wears through.