//Quick answer
- PEX: flexible, fewer joints, resists pitting; must be kept from sunlight.
- Copper: rigid, proven, visible connections; subject to pinhole pitting over time.
- Both are permitted work; the repipe range is $18,000 to $30,000 either way, by bathroom count.
01Definition
What is PEX?
Cross-linked polyethylene tubing joined with crimp, clamp or expansion fittings. It snakes through walls and attics with fewer joints than rigid pipe, resists scale and pinhole corrosion, and tolerates movement.
02Which fits
When does PEX fit?
Slab homes where lines route through attic and walls, houses with hard water history, and repipes where fewer joints and faster installation matter. It cannot be exposed to sunlight and is not used at the water heater's immediate connections.
When does copper fit?
Owners who prefer a rigid, metal system, exposed runs where the pipe will be seen, and the connections at fixtures and the water heater on any repipe. Its known failure mode over decades is pinhole pitting from water chemistry, which is often the reason the repipe is happening.
//Side by side
PEX
- Flexible; fewer joints
- Resists scale and pinhole pitting
- Handles movement; faster install
- Must be kept from sunlight
- Copper still needed at some connections
Copper
- Rigid and long-proven
- Fine for exposed runs
- Standard at fixtures and the water heater
- Pinhole pitting over decades
- More joints; slower install
03What goes wrong
What goes wrong with either?
Bad joints. A PEX crimp made with the wrong tool or a copper joint soldered cold fails the same way: inside a wall, later. The permit inspection at rough-in, with the system under pressure, exists to catch exactly that.
04Proof
- Sandy Zamarripa, Google, September 4, 2026: "The technician, Daniel was patient and explained everything that was needed to be done to re-pipe the house."
- When a job needs a permit, Done-Rite pulls it and schedules the inspection.
- 1 year minimum warranty on labor. Manufacturer warranty handling varies by manufacturer.
- Six plumbers averaging more than 9 years in the trade each, plus a General Manager with 25+ years.
05Action
Have both explained for your house
Repipe $18,000 to $30,000 by bathroom count, permitted and inspected, 1 year minimum labor warranty. Financing available with terms up to 10 years.
//Keep going
Learn
Compare
//Terms used in this guide
Where this applies
Done-Rite runs these calls across Orange County from its shop in Anaheim, CA, with no trip charge in any city it serves.
Common questions
Both are used for repipes, and each has trade-offs. Done-Rite explains them for your house, with no pressure either way.
