Water supply pipes are mainly available in two materials—copper and cross-linked polyethylene, or PEX. Copper has historically been a common piping material. It is still widely used, while PEX flexible tubing is becoming more common in residential plumbing, as an alternative to copper as well as chlorinated polyvinyl chloride (CPVC) piping. Here, we will compare various attributes to help you weigh PEX vs. copper for your next plumbing update.
Longevity
The average lifespan of copper pipes is 50 to 70 years. That doesn’t mean a copper line can’t fail in just a few short years, but with good maintenance and repair, it tends to last. Acidic water can shorten its lifespan. Your plumbing contractor can test your water supply to determine whether it has high acid content.
PEX pipe generally lasts about 20 years less than copper. However, PEX pipe has more recently grown in popularity, so its true potential isn’t completely known, especially its resistance to corrosion and sediment buildup. Although it tends to degrade faster than copper, PEX tubing can last around 50 years if properly maintained.
Cost
Copper and products made from it are costlier. According to Bob Vila, copper water pipes cost around 58% to 68% more than PEX.1 Depending on the installation, it can be as much as 3x more expensive. Repiping with copper can be cost-prohibitive. However, copper pipes are recyclable, so you can sell scrap pipes for cash.
Installation
To install copper pipes, pipes and elbow fittings (needed at every corner) must be soldered together. Specialized fittings are available. However, these are prone to leaks that can quickly degrade copper lines. Heavy-duty tools require a professional plumber to use, so whether you need to install, modify, or cut pipe, it can be difficult without the right experience.
Meanwhile, PEX pipes are easier to install, even for a DIYer. They require fewer connections and can bend easily around corners and snaked through finished walls. Quick-connect fittings allow one to push pipe sections together. You can often run a single tube continuously from the water distribution manifold to a sink, tub, or other fixture. There’s no need to remove drywall, which reduces effort, time, and expenses.
Also, PEX is colored blue for cold water and red for hot water, making pipes instantly identifiable.
Durability
Copper became popular in the 1970s as an alternative to metal pipes that could release lead and various chemicals. While naturally stable, it is highly susceptible to corrosion depending on water chemistry. If chloramines are present, copper pipes can corrode rapidly. Electrolysis can occur when copper interacts with minerals or electrical components, possibly triggering corrosion and pinhole leaks.
PEX pipes are less prone to freezing and breaking than copper. If you’ve had issues with water pipes freezing, PEX pipes are a practical replacement. They are also most durable when installed indoors, as exposure to sunlight can cause the material to degrade quickly.
Health/Environmental Impacts
A study by Purdue University found that PEX pipes, while less expensive than copper, contain various chemicals that can leach into water when the pipe starts to degrade. Leaching was detected even during the early days of testing. Unpleasant odors can often result from this. At times, PEX was found to exceed water quality standards of the U.S. Environmental Protection Agency (EPA).
However, the Journal of Cleaner Production found the use of PEX pipes instead of copper pipes can substantially reduce carbon dioxide emissions over their lifespan.
 Schedule Pipe Installation/Replacement Today
At Sky Heating & Air Conditioning, we specialize in installing and servicing PEX and copper pipes. In some cases, we combine both for a solution that supports multiple fixtures and tolerates high water pressures. To request a free evaluation in Portland and The Dalles, or receive help weighing a decision between PEX vs. copper, schedule your piping or repiping appointment online or call 503-673-9083 today.