Do this now
- Shut off the main water valve — usually where the water line enters the house, near the meter.
- If water is near outlets, appliances or the electrical panel, turn off power to that area at the breaker — but only if you can reach the panel without standing in water.
- Open the lowest faucet in the house to drain the lines, and flush toilets to empty them.
- Move belongings, catch what you can, and start removing standing water.
- Photograph the damage before you clean up, then call a plumber and your insurer.
What usually causes it
- Freezing in an unheated space or outside wall
- Corrosion in old galvanized steel or copper lines
- A failed fitting, washing-machine hose or supply connector
- Water pressure that is too high for the system
What a professional will do
A plumber cuts out the damaged section and replaces it, pressure-tests the repair, and looks for the cause so it does not happen again — corrosion elsewhere on the same run, a missing pressure-reducing valve, or a pipe that needs rerouting. Wet drywall, insulation and flooring often need professional drying to prevent mold.
How to prevent it
- Know where the main shutoff is and make sure everyone in the house can operate it
- Replace rubber washing-machine hoses with braided stainless ones
- Have aging galvanized supply lines assessed before they fail
- Protect pipes in unheated areas before winter
Rules and paperwork in Pennsylvania
- Pennsylvania’s Home Improvement Consumer Protection Act requires most contractors who perform home improvements to register with the Attorney General’s office and to give you a written contract for any job over $500. The registration number belongs on the estimate and the contract — ask for it.
- Building permits in Pennsylvania are issued under the Uniform Construction Code by each municipality or the inspection agency it appoints, so the local building or codes office decides what needs a permit and an inspection.
- Pennsylvania does not issue a statewide license for this trade. Some municipalities register or license it locally, which is one reason to confirm requirements with your own municipality.
Sources: Pennsylvania Office of Attorney General — Home Improvement Consumer Protection Act; Pennsylvania Department of Labor & Industry — Uniform Construction Code; Pennsylvania Department of Labor & Industry. Rules change — confirm current requirements with the agency and with your municipality.
Frequently asked questions
Where is my main water shutoff?
Usually on the front basement wall where the water service enters, close to the meter. Homes on a slab often have it in a utility closet or near the water heater. Find it before you need it.
Can I use a repair clamp myself?
A clamp or push-fit coupling can hold as a temporary repair once the water is off, but it does not address why the pipe failed. Have a plumber make the permanent repair.
How quickly do I need to dry things out?
As soon as possible. Materials that stay wet for more than a day or two can grow mold, so start drying immediately and bring in professional drying for anything more than a small area.
Go deeper
Our full plumbing guide covers how the work is done, what affects the price, and what to ask before you hire, and there is more on leak repair.
Plumbing help by town
Related problems
This guide is general information, not a substitute for a professional assessing your home. If you are unsure whether something is safe, treat it as if it is not.