How long do plumbing pipes last?
Updated August 2026
How long plumbing pipes last comes down almost entirely to material: copper supply lines run 50–70 years, PEX 40–50, and old galvanized steel is rated 40–50 but usually clogs and corrodes long before that. On the drain side, cast iron lasts 75–100 years and modern PVC essentially outlives the house. Water chemistry sets the pace, since acidic or very hard water attacks copper and steel, while galvanized pipe rusts shut from the inside no matter how gently you treat it. A whole-house repipe runs $4,000–15,000, so knowing what you have is worth the crawl-space trip.
Lifespan by type and situation
| Type or situation | Typical lifespan | Why |
|---|---|---|
| Copper supply pipe | 50–70 years | Durable, but acidic water pinholes it early |
| PEX (cross-linked polyethylene) | 40–50 years | Flexible and freeze-tolerant; keep it out of UV light |
| CPVC supply pipe | 40–75 years | Cheap and corrosion-proof, but grows brittle with age |
| Galvanized steel supply | 40–50 years | Rated high, but rusts shut and drops pressure sooner |
| Cast-iron drain line | 75–100 years | The old drain standard; corrodes and cracks late in life |
| PVC or ABS drain line | 100+ years | Effectively lasts the life of the house |
| Polybutylene (gray, 1978–1995) | Replace now | Prone to sudden failure; insurers often refuse it |
Signs yours is near the end
- Water that comes out rusty, brown, or tinted after sitting overnight
- Steadily falling water pressure, the classic sign of galvanized pipe rusting shut
- Recurring pinhole leaks or green stains on copper lines
- Visible corrosion, flaking, or dimpling on exposed pipe
- A metallic taste, or stains in tubs and sinks from dissolved metal
- Several leaks in a short span, a hint the whole system is aging out
How to add years
You cannot stop a pipe from aging, but water chemistry is the lever that moves the number. If your water is acidic (low pH) or very hard, a whole-house treatment or softener slows the pitting that pinholes copper and the scale that narrows every line. Keep water pressure below about 80 psi with a pressure-reducing valve so the system is not hammered around the clock, and insulate pipes in unconditioned space so a freeze never splits them. Fix small leaks fast, since a slow drip corrodes fittings and rots framing. If you still have galvanized or, worse, polybutylene, budget a repipe on your terms rather than after a flood; a running maintenance checklist keeps leak checks and pressure tests on schedule, and the drain side ages alongside the sewer line that carries it away.
What it costs to replace: plan on $4,000–15,000 for a whole-house repipe. Replacing on your own schedule, before it fails, is almost always cheaper than the emergency version. The home maintenance cost calculator helps you set the money aside before it comes due.
OnOtto tracks your plumbing inspections age and service history, and warns you before end of life instead of after the flood.
Track your home's systems, free for 30 daysFrequently asked questions
Do I need to repipe my house, and when?
You repipe when failures stop being one-offs. A single leak is a repair; recurring pinholes, browning water, pressure that keeps dropping, or several leaks in a year mean the material is aging out and patching just chases the next break. Galvanized supply lines past 40–50 years and any polybutylene are prime candidates regardless of symptoms. A whole-house repipe runs $4,000–15,000, but doing it on your schedule beats an emergency after a burst line floods a finished room.
Which pipe material lasts the longest?
On the supply side, copper has the longest track record at 50–70 years and can push past that in friendly water, though acidic water pinholes it sooner. PEX is newer but rated 40–50 and shrugs off freezing and corrosion, which is why it dominates new construction. On the drain side, cast iron reaches 75–100 years and PVC essentially outlasts the house. The real answer is that clean, balanced water lets any good material hit the top of its range.
How can I tell what kind of pipes my house has?
Look where pipes are exposed, at the water heater, in the basement, or under sinks. Copper is dull bronze and often has soldered joints; PEX is flexible plastic tubing in red, blue, or white with crimped rings; galvanized is dull gray threaded steel that a magnet sticks to; polybutylene is gray or bluish plastic with banded fittings, mostly installed from 1978 to 1995. Your home's build year narrows it fast. If you see gray plastic supply lines, have a plumber confirm whether it is polybutylene.
Is galvanized or polybutylene pipe a problem?
Both are worth replacing. Galvanized steel rusts from the inside, so it slowly strangles water pressure and dumps rust into your water, and by 40–50 years it is usually near the end. Polybutylene, the gray plastic supply pipe used from 1978 to 1995, is worse: it can fail suddenly without warning, and many insurers will not cover a home that still has it. If you find either, plan a repipe rather than waiting for the leak that forces one.