Repiping & Whole-Home Pipe Replacement
Replace worn galvanized, copper or older plastic pipe through the whole house.
Plumbing guide
PEX vs Copper Pipe: Which Is Better for Your House?
Both PEX and copper deliver safe water for decades. The choice comes down to the house, the water and the job, and neither one wins on every point.
By the Urban Comfort Plumbing team ·
What PEX and copper are
Copper is a rigid metal pipe that has been used in houses for generations. It is joined with soldered fittings, or with push or press fittings, and it comes in different wall thicknesses. PEX, short for cross-linked polyethylene, is flexible plastic tubing that comes in coils and is joined with crimp, clamp or expansion fittings.
PEX has been used in homes for several decades and is accepted by most plumbing codes, though local rules and the manufacturer's instructions apply. Both materials are used in new construction and in repipes. Ask your plumber which one they recommend for your house and why.
Installation and disruption
PEX bends around corners and runs in long sections, so a repipe needs fewer joints and fewer openings in walls. A plumber can fish it through attics and wall cavities with less cutting. A manifold system, where each fixture has its own line from a central panel, is common with PEX and lets you shut off one fixture without affecting the others. The Plastic Pipe Institute's PEX installation guide says not to store or use PEX where it will be exposed to direct or reflected sunlight, notes that each manufacturer publishes its own maximum UV exposure time, and tells installers to follow local codes and the manufacturer's limits.
Copper is rigid and needs fittings at every turn. That means more joints and more places for a joint to fail, and it takes more time. A skilled installer produces durable work with copper, but the labor is higher. On a house with finished walls, the lower disruption of PEX is a major advantage.
Cost
PEX is generally less expensive in materials and in labor. Copper prices rise and fall with the metal market and have been high at times, and copper pipe is also a theft target on vacant job sites. Fittings, tools and the time to solder add to the cost.
Price depends on the house, the number of fixtures, the access and the scope. Compare quotes on the same basis: same material, same wall and ceiling repair, same permit. A low price for PEX that leaves out the drywall work may not be lower in the end.
Lifespan and failure modes
Copper has a long track record, and a properly installed system can last for many decades. Its enemies are aggressive water, which can cause pinhole leaks from the inside, and soil or concrete that attacks the outside of buried pipe. Pinholes often show up in clusters, and when they do, patching one at a time is a losing game.
PEX does not corrode, and its smooth interior resists scale. It can fail at fittings that are poorly installed, and sunlight breaks it down, so it must be kept out of UV exposure and covered or stored away from the sun. Manufacturers quote long service lives, and warranties vary, so ask for the specifics of the product being installed.
Water quality and taste
Both materials are used for drinking water and meet standards for it. Some people notice a plastic taste from new PEX for a short time, which flushing the lines reduces. Copper can add a faint metallic taste in some water. Chloramine, the disinfectant used by the City of St. Petersburg, is harder on some rubber and plastic parts than chlorine, so ask the plumber to use fittings and parts rated for it.
If water is aggressive and has caused pinhole leaks in copper, PEX avoids that failure. If you have concerns about taste or contaminants, water filtration addresses them whichever pipe you choose.
Where each one fits
PEX suits whole-house repipes, slab-leak reroutes through the attic and new construction, where long runs and few joints matter. It is also useful in tight spaces. Copper suits exposed runs, places with sunlight, and areas where a plumber or owner prefers metal. Some houses combine them, using copper for exposed runs and PEX inside the walls.
If your house still has polybutylene, a gray plastic used in many homes from the late 1970s through the mid 1990s, replacing it is worth discussing. See repiping for how a whole-house replacement works, and slab leak repair for reroutes.
How the joints are made
Copper joints are traditionally soldered with a torch, which needs hot work and care around framing. Press fittings use a tool to crimp the joint without heat, which is faster and safer in tight spaces. PEX fittings are crimped with a copper ring, clamped with a stainless band or expanded and then shrunk onto the tube. Each method has tools and training behind it, and each is reliable when done properly.
The fitting matters because most leaks start at joints. Ask what method will be used and whether the installer is trained in it. A system with fewer joints, as PEX often has, simply has fewer places for something to go wrong.
What the repipe looks like on site
For either material, expect the water to be off for part of the day or longer. The plumber locates the main valve, plans the routes and opens small access holes in drywall where needed. New lines go in, the system is pressure tested, and then the fixtures are reconnected. Patching and painting the access holes comes last and may be handled by another trade.
Ask for a schedule that keeps water on overnight, and ask how long the longest shutoff will be. If you work from home or have small children, that detail matters.
Hot water lines and recirculation
Both materials work for hot water, but there are details. PEX has temperature and pressure ratings that must match the water heater's setting, and copper conducts heat, so uninsulated hot lines lose more of it. Insulating hot lines saves energy with either one, and a recirculation loop that keeps hot water moving shortens the wait at the tap. Ask whether the design includes insulation and whether the loop is worth it for your house.
Questions to ask your plumber
Ask which material they would use and why. Ask how the fittings are made and who warrants them. Ask about the manifold layout, the shutoff valves and where they will be. Ask about permit, inspection and wall repair. Ask what the system will be tested at before the walls are closed, and whether you can see the test.
Whatever you choose, the quality of the installation matters more than the pipe. A poorly installed system in either material will fail sooner than a well-installed one.
Common questions
PEX and copper questions
Yes, PEX approved for potable water meets drinking water standards. Flush new lines before use.
Both can last for decades. Water chemistry, installation quality and conditions decide it. Ask for warranty details on the product being used.
Not exposed to sunlight, which degrades it. It must be covered or kept out of UV.
Usually yes. A licensed contractor normally handles the permit and inspection.
Related services
Slab Leak Detection & Repair
Locate and fix a leak under the concrete slab that many St. Pete homes sit on.
Water Line Repair & Replacement
Repair or replace the pipe that carries water from the meter into the house.
Thinking about repiping?
Call and describe the house and its leaks. The dispatcher will connect you with a local contractor.