Pipe problems
When to repipe a house
Updated · Editorial team; not yet technically reviewed
Short answer
Repiping makes sense when the supply pipe itself is failing: galvanized steel that's rusting from inside, polybutylene known for failures, or copper with repeated pinhole leaks. Rusty water, falling pressure and a second or third leak in a year are the usual signs. Most repipes use PEX or copper and take a few days for a typical house.
Signs it's time
- Galvanized supply pipe in a house built before the 1960s or so.
- Gray polybutylene supply line, common in homes from roughly 1978 to 1995.
- Pinhole leaks in copper in more than one place.
- Rusty or discolored water, especially first thing in the morning.
- Pressure that drops when two fixtures run at once.
PEX or copper?
| PEX | Copper | |
|---|---|---|
| Installation | Flexible runs, fewer fittings, faster | Rigid, soldered or press fittings |
| Cost | Usually lower | Usually higher |
| Freeze tolerance | Expands somewhat; more forgiving | Splits more readily |
| Water chemistry | Resists scale and corrosion | Can pit in aggressive water |
| Outdoor and sunlight | Must be protected from UV | Fine |
What the job involves
Plan the routes
Through walls, attic or crawlspace to each fixture.
Open small access holes
Not whole walls; patches follow.
Run and connect new lines
Usually fixture by fixture so water is off only for short periods.
Pressure test and inspect
Most jurisdictions require a permit and inspection.
Planning around a repipe
Most whole-house repipes in occupied homes take a few days, and water is usually off only during the working day. Plumbers open small holes in drywall at fixture locations and run new lines through attics, crawlspaces or basements; ask whether patching and painting are included, since many plumbers repair the drywall but leave the painting to you. Clear access to the water heater, under sinks and along exterior walls speeds the job.
A repipe is a good time to add shutoff valves at every fixture, replace old hose bibs, install a pressure reducing valve if pressure is high, and relocate lines away from exterior walls in cold climates. Confirm that the permit and final inspection are included, and keep the inspection card: buyers and insurers increasingly ask when supply lines were replaced, and documented work removes a common inspection objection to older homes.
Ask the plumber to label new shutoffs and leave a simple sketch of where the main lines run, so later remodeling crews don't drill into them.
Common questions
How do I know if I have galvanized pipes?
They're gray steel with threaded fittings; a magnet sticks to them, unlike copper or plastic.
Why is polybutylene pipe replaced?
It was widely used from about 1978 to 1995 and became known for failures as it ages.
Is PEX as good as copper for repiping?
Both are durable; PEX is usually cheaper and faster to install, copper suits exposed and outdoor runs.
Is a permit needed to repipe a house?
Most jurisdictions require a permit and a pressure-test inspection for repiping.
Can I live in my house during a repipe?
Usually yes; water is off for parts of each day.
Do pinhole leaks mean I need to repipe?
One can be repaired; leaks in several places suggest the copper is failing throughout.
General information; codes vary by location. See our editorial standards.