Burst pipe, no water, a water heater dumping on the floor, or sewage coming up in a ground-floor unit? Send a few details and you’ll get a straight answer from one vetted, licensed San Francisco plumber — not five companies fighting over your phone number.
If water is actively flowing, shut off the fixture stop or the main first, then tell us what’s happening, when it started, and whether it’s reaching other units in the building.
What counts as a plumbing emergency in San Francisco is usually one of a few things: a supply line that’s burst or is spraying, a total loss of water, a sewage backup coming up through a low fixture, or a water heater that’s ruptured. In this city, the stakes are higher than the plumbing alone, because so much of the housing is stacked. A failure in a top-floor flat runs down through the units below it, and a burst line in a shared wall becomes several households’ problem within minutes. The first move on almost any of them is the same: stop the water at the fixture stop, and if that won’t hold it, at the building’s main shutoff.
The age of the building is usually the reason it happened. San Francisco’s older flats still run galvanized-steel supply and cast-iron drains that corrode from the inside; a pinhole in mid-century copper, a split in a corroded galvanized nipple, or a cast-iron stack that finally rusts through are the classic after-hours calls. Knowing the building’s vintage and where its shutoffs are — the fixture stops, the water heater’s cold-side valve, and the main — is what turns a flood into a contained mess.
If you smell gas
A gas smell is a different kind of emergency and it isn’t a wait-for-a-plumber situation. Leave the building, don’t switch anything electrical on or off, and call PG&E from outside — they respond to suspected leaks at no charge and will make the line safe. Once the leak is isolated, a licensed plumber handles the repair and the re-pressurization test and permit. If you’re unsure whether what you smell is gas, treat it as gas.
What can usually wait until morning
Not everything that feels urgent needs an after-hours rate. A single slow drain, a dripping faucet, a running toilet you can shut off at the stop, or a water heater that’s merely stopped making hot water — without leaking — are almost always fine to handle on a normal visit, and you’ll pay less for it. An honest plumber will tell you which category you’re in rather than sell you an emergency you don’t have. Describe what’s happening and you’ll get that read straight.
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San Francisco emergency plumbing questions
Where is my water shutoff in a San Francisco flat?
Start at the fixture — most sinks and toilets have a small stop valve where the supply meets the wall. For a bigger failure, the building’s main shutoff is usually in the garage, the basement, or near the front where the service enters; in a multi-unit building there may be a shared main plus per-unit valves. It’s worth locating yours before you ever need it.
A pipe burst and it’s reaching the unit below — what first?
Shut the water — the fixture stop if it’s one fixture, the main if you can’t isolate it — then move to contain and get eyes on the unit below, since in a stacked building the damage travels down. Once the water is off, send the details and a plumber can advise on the repair and whether the wall needs opening to dry and fix the line.
Do I call a plumber or PG&E for a gas smell?
PG&E, first, from outside the building — they respond to suspected gas leaks at no charge and make the line safe. A plumber does the actual repair and the code-required pressure test and permit afterward. Don’t operate light switches or appliances while you suspect a leak.
Send your San Francisco plumbing emergency
Tell us what’s failing and whether the water is off, and you’ll get a fast, honest read on what needs doing now and what can wait — no pressure, no manufactured emergency.
Just a clear answer from the one vetted, licensed San Francisco plumber who’d actually do the work.