Polybutylene Pipe
Polybutylene is a gray, blue or black plastic water pipe installed in many US homes from about 1978 to 1995. It can become brittle and fail without warning, and some insurers limit coverage for homes that have it. Replacing it usually means repiping, typically $4,000 to $15,000 with PEX.
Typical pro cost
$4,000 to $15,000
- Urgency
- Plan soon
- DIY difficulty
- Hard
- Time to fix
- 2 to 5 days (pro)
- Prices
- US typical range
Last reviewed September 2026
Signs it's this problem
- Flexible gray, blue or black plastic pipes
- Marked PB2110 on the pipe
- Home built between about 1978 and 1995
- Plastic or metal crimp fittings
- Recurring pinhole leaks or sudden bursts
Common causes
Chlorine reaction
Oxidants in treated water break down the pipe from the inside.
Brittle fittings
Early plastic fittings crack; metal crimp rings can be improperly installed.
Age
Most polybutylene is now 30 to 45 years old.
How to fix it, step by step
- 1
Check exposed pipes near the water heater, under sinks and at the main shutoff for PB2110 markings or gray plastic pipe.
- 2
Look at the main supply line coming into the house; it may be polybutylene too.
- 3
Call your insurer to ask about coverage limits.
- 4
Get quotes to repipe with PEX or copper, including wall patching.
- 5
Consider repiping before selling; many buyers and lenders ask about it.
- 6
Until then, know where your main shutoff is and consider leak detectors near fixtures.
Tools and materials
- Flashlight to inspect pipes
- Water leak sensors
Approximate DIY cost: Not a DIY job
Call a pro when
- Whole-house repiping
- Replacing the main supply line
- Frequent leaks
Polybutylene Pipe cost
| Job | Typical cost |
|---|---|
| Repipe a house with PEX | $4,000–$15,000 |
| Repipe with copper | $8,000–$20,000 |
| Replace main water supply line | $1,500–$5,000 |
| Drywall patching after repipe | $500–$3,000 |
Ranges are typical US prices compiled by FixHomeCost. Prices vary by region, home and contractor, so compare 2–3 local quotes.
Common questions
How do I know if I have polybutylene pipes?
Look for flexible gray, blue or black plastic pipe marked PB2110, often with crimp fittings, in homes built from about 1978 to 1995.
Is polybutylene pipe dangerous?
It is not toxic, but it can fail suddenly and cause major water damage.
Will insurance cover a home with polybutylene pipes?
Some insurers refuse coverage or exclude water damage from these pipes. Ask your insurer directly.
PEX or copper for replacing polybutylene?
PEX is cheaper and faster to install; copper lasts a long time but costs more. Both are common replacements.
Related guides
This is general information, not a professional inspection. See how we research costs.