PEX (cross-linked polyethylene) plumbing has become incredibly popular over the past two decades and for good reason. It’s affordable, flexible, and easier to install than traditional copper or PVC pipes. Many homeowners choose PEX because it promises quick installation and lower costs.
However, not everything about PEX plumbing is as good as it seems. Over time, several issues have emerged that can affect water quality, durability, and even your home’s safety. If you’re considering using PEX pipes or already have them, it’s important to understand the potential downsides before you commit.
Let’s break down the common problems with PEX plumbing and why some experts believe it’s not the best long-term choice.
What Is PEX Plumbing?
PEX is a type of plastic tubing made from cross-linked polyethylene. It was designed to be a modern alternative to copper and CPVC pipes. The material is flexible, lightweight, and color-coded, red for hot water, blue for cold, and white for general use.
Because it can bend easily and requires fewer fittings, PEX is widely used for residential water supply lines and radiant floor heating. But unlike metal pipes, PEX is still plastic and that comes with unique limitations.
Why Some Experts Say PEX Plumbing Is a Bad Choice
1. Chemical Leaching Concerns
One major drawback of PEX is the potential for chemical leaching. Since PEX is made from plastic polymers, it can release trace amounts of chemicals into the water — particularly when the pipes are new or exposed to heat.
Studies have detected compounds like MTBE and toluene in certain PEX systems. While these are usually within safety limits, they can still affect the taste and odor of your drinking water. If you’ve ever noticed a “plastic” taste from your taps, PEX may be the culprit.
2. Damage from Sunlight (UV Sensitivity)
PEX is extremely sensitive to ultraviolet (UV) light. Even short-term exposure to sunlight can weaken the material and make it brittle.
For this reason, PEX should never be stored outdoors or installed in places exposed to sunlight, like attics or near windows. Even improper storage before installation can cause long-term damage, leading to cracks or leaks years later.
3. Shorter Lifespan in Harsh Conditions
PEX manufacturers often claim their products last 40–50 years, but that lifespan depends on the environment. In areas with high chlorine levels, hard water, or extreme temperatures, PEX may degrade much faster.
By comparison, copper pipes can easily last 70 years or more and are much more resistant to fluctuating water conditions.
4. Prone to Rodent Damage
PEX’s flexibility makes installation easier but it also makes it more appealing to rodents. Mice and rats can chew through PEX tubing, causing leaks and water damage.
This problem is especially common in basements, crawl spaces, and walls where rodents may roam. Even with insulation or barriers, there’s always a risk because the material itself isn’t rodent-resistant.
5. Uncertain Long-Term Reliability
Unlike copper and CPVC, PEX hasn’t been around long enough to prove its durability over many decades. Early versions of PEX systems have already shown problems with leaks and corrosion.
Some fittings made of brass were found to fail prematurely due to dezincification, a process that causes metal components to weaken and corrode.
Not all PEX is the same either:
- PEX-A is flexible and durable but more expensive.
- PEX-B is cheaper and stiffer, but more prone to cracking.
- PEX-C is the most affordable, but also the least reliable.
6. Plastic Odor and Taste in Water
Another common complaint about PEX plumbing is the “plastic” taste or smell in water. This usually happens because certain compounds inside the pipe interact with the water — especially hot water.
While the odor often fades after a few months, it’s still a sign that the pipe material is affecting your water quality.
7. Vulnerable to Chlorine and Chemicals
PEX doesn’t handle chlorine well. Municipal water systems that use chlorine or chloramine for disinfection can slowly damage PEX over time, leading to cracks, discoloration, and leaks.
This makes PEX less suitable in areas with chemically treated water unless protective measures are taken.
8. Installation and Fitting Issues
PEX installation may look simple, but it requires the right fittings, crimp tools, and experience. A single improper crimp can cause hidden leaks that go unnoticed for months.
Additionally, fittings are not universal mixing components from different manufacturers can cause premature failure or pressure loss.
PEX vs. Copper and CPVC: A Quick Comparison
| Feature | PEX | Copper | CPVC |
|---|---|---|---|
| Cost | Low | High | Moderate |
| Durability | Moderate | High | High |
| Chemical Safety | Questionable | Excellent | Good |
| UV Resistance | Poor | Excellent | Fair |
| Rodent Resistance | Poor | Excellent | Good |
| Lifespan | 40–50 years | 70+ years | 60+ years |
PEX may be cheaper upfront, but copper and CPVC often provide better safety, stability, and long-term value.
PEX Failures and Lawsuits
PEX plumbing hasn’t been without controversy. Some well-known manufacturers — including Kitec, Zurn, and Uponor have faced lawsuits over premature failures, corrosion, and leaks.
In the case of Kitec, the product was recalled entirely due to widespread corrosion issues. These incidents highlight the importance of careful product selection and expert installation.
When PEX Can Still Be Useful
Not all situations call for copper. PEX can be a smart choice for short-term installations, remodels, or radiant heating systems where flexibility and low cost are priorities.
When used indoors, away from sunlight and rodents, and installed correctly, PEX can serve reliably for years. Still, it’s best to consult a professional before deciding if it’s right for your home.
Tips for Homeowners Considering PEX
- Choose trusted brands like Uponor or Viega
- Store and install PEX away from sunlight
- Protect pipes in crawl spaces or attics from rodents
- Flush the system before first use to remove odor
- Hire certified plumbers experienced in PEX systems
Conclusion
PEX plumbing offers flexibility and affordability but it’s not without its flaws. From chemical leaching and UV sensitivity to rodent damage and questionable longevity, it may not be the best fit for every home. If you’re looking for a plumbing system that lasts decades with minimal maintenance, it’s worth comparing all your options carefully.
At Dan Wood Services, we’ve helped thousands of Michigan homeowners make the right choice for their plumbing needs. Our team understands the pros and cons of every system — whether it’s PEX, copper, or CPVC and we’ll recommend the best solution for your home’s water quality, budget, and long-term comfort.
If you’re thinking about replacing your plumbing or have concerns about your current PEX system, contact Dan Wood Services today. We provide honest advice, expert installation, and dependable service that Michigan homeowners have trusted for decades.
Dan Wood Services, where your comfort, safety, and satisfaction always come first.