Shut the water off first
Most outdoor faucets have their own shutoff valve inside, usually on the pipe running to that wall in the basement ceiling. If you can't find it, or it won't close, use the house-side valve next to the water meter, which the Philadelphia Water Department says is the one to use in an emergency. Don't keep opening the outside faucet to see whether it's still leaking.
In Philadelphia, every pipe from the water main into your house is the owner's responsibility, so the Water Department won't repair it. It points homeowners to a licensed and registered plumber and keeps the contractor lookup at phila.gov/li. If the meter itself is leaking, that's the Water Department's call: (215) 685-6300.
Check for electrical hazards before you go near the wet area
Look for water near outlets, switches, light fixtures or a panel before you walk over. The CDC says that if electrical circuits or equipment are wet or sitting in water, turn power off at the main breaker, but never step into standing water to reach it; call an electrician instead. Don't switch power back on to anything that got wet until an electrician has checked it.
How to tell where the leak is
Horizon, a home inspection reference, notes that leakage from a frost-proof faucet often shows up only inside the building while the faucet is flowing, and that a split pipe is more often found inside the wall than outside. That gives you two patterns worth reporting:
- Water appears indoors only while the outside faucet is open. That points to a split in the faucet's long body or the pipe right behind it.
- Water keeps coming with the outside faucet closed. The break is probably on the supply side, before the faucet's valve, and the shutoff matters more urgently.
To check whether anything is still running with everything closed, use the water meter to look for a hidden leak. Philadelphia Water's own advice is that the first sign of freezing is reduced flow at a faucet, so if the outdoor faucet gave a trickle during the cold snap and then leaked once it warmed up, mention that too.
What to tell and ask the plumber
Before the visit, take a photo of the outside faucet, the wet area inside and the shutoff you closed, plus one wider shot showing where they are in relation to each other. Write down when you noticed the leak and whether a hose, splitter or timer was left on the faucet during the freeze; the Water Department tells homeowners to disconnect hoses before winter.
Then ask:
- Which part failed: the faucet body, its connection, or the supply pipe?
- If it's a frost-free faucet, is it pitched slightly downward toward the outside? Federal building guidance from the Building America Solution Center calls for that slope, and for outdoor-faucet shutoffs to be reachable from indoors.
- Will you run the water and check the new connection for leaks before the wall is closed up?
- Does this repair need a permit? Rules vary, so see which plumbing jobs need a Philadelphia L&I permit if you're in the city, or ask your township in Bucks or Montgomery County.
Deal with the wet wall the same week
Stopping the leak doesn't dry the wall. The EPA's water-damage table is built around acting within 24 to 48 hours to head off mold. It says drywall may be dried in place if it isn't visibly swollen and the seams are intact; otherwise it gets cut out and replaced, and the wall cavity should be ventilated if possible. Wet fiberglass or cellulose insulation is discarded and replaced. Even materials dried within 48 hours can still grow mold, so ask whoever does the drying how they'll confirm the cavity is dry before it's closed and painted. More on that call is in whether wet drywall can be dried out or needs replacing.
Those EPA steps are for clean water, which a supply leak is. If you find mold already growing, leave it for a qualified remediation contractor rather than scraping it yourself.
Before next winter
Philadelphia Water's routine for outdoor faucets is to disconnect the hose, close the faucet's dedicated indoor shutoff, and then leave the outside faucet open so the short section of pipe can drain. The Building America guide also suggests insulating covers over outdoor faucets in winter. If your faucet has no indoor shutoff or isn't pitched outward, ask the plumber to fix that while the wall is open.