Copper and PEX are two of the most prevalent plumbing materials in the world. Humans have used copper for plumbing for thousands of years. Standardized copper tubing became available in the 1920s. It soon accounted for more than 90% of indoor plumbing in the United States. PEX is a newer plumbing material. A German inventor developed it in the late 1960s. Usage became widespread in Europe soon after. It became widespread in the U.S. in the 1980s.
Copper Piping
Copper tubing remains ideal for heating systems and HVAC refrigerant lines. PEX has supplanted it for cold- and hot- water use in the U.S. and throughout much of the world. Copper tubing is available in three core grades: M, L, and K. K has the greatest wall thickness. M has the least.
The copper piping manufacturing process makes the metal rigid. Rigid copper is the most popular and affordable choice for water lines. Manufacturers can anneal copper piping. This process makes it soft or ductile and allows it to be easily bent once again. You have the choice of rigid or soft with either of the three grades.
PEX Piping
PEX is an abbreviation for cross-linked polyethylene. It is sometimes abbreviated XPE or XLPE. In the 1960s, polyvinyl chloride or PVC began to supplant copper piping for plumbing. Chlorinated PVC or CPVC would later supplant PVC due to its higher chlorine and temperature tolerance. PEX is a plastic piping like PVC and CVPC. A main advantage of PEX is that it’s much more flexible.
Copper vs. PEX: Building Codes
Federal and all state building codes have long approved copper piping for plumbing. You must check local ordinances to determine the appropriate grade per application.
Federal code approves of PEX usage and sets the standards for the material in ASTM F876 and F877. Official adoption of PEX has been slow. The National Standard Plumbing Code now approves it, but that change occurred within the last 15 years. All states now approve it as well. California was the last holdout but soon followed the NSPC. Note that some local codes still disallow it.
Copper vs. PEX: Pricing
Copper is a finite resource. The world is now facing a copper shortage. Growth in the automotive and energy transition industries are driving this demand. As demand increases and supply decreases, prices rise. If re-piping your home, you can expect to pay four to five times more for copper than PEX. That can result in a significant cost difference for large-scale plumbing projects. Price disparities are largely what drove innovations in PVC, CPVC, and PEX.
Copper vs. PEX: Longevity
Copper offers greater longevity but not by a significant margin. With proper maintenance, copper pipes will last at least 50 years and can last 70 years or more. PEX piping will generally last 50 years. Maintenance is important with PEX as well. But longevity of PEX often comes down to environmental conditions.
You may see estimates that put PEX at 25 years or even less. It’s important to note that such estimates are outdated. They were also largely fueled by some high-profile but isolated cases in the 80s and 90s. Refined manufacturing techniques have resulted in a higher-quality product. Our society has also made great strides in how we treat water and protect indoor plumbing.
Copper vs. PEX: Installation Time
This an area where PEX shines. It’s a much easier material for plumbers to work with. This substantially cuts down on installation time. Re-piping a home can take twice as long when working with copper. When considering your budget, it goes beyond the material cost. Having your plumber install copper pipes is going to cost you considerably more in labor as well.
Copper vs. PEX: Flexibility
The reason PEX is easier to work with is that it is more flexible. It fits into tight spaces, and your plumber can bend it as needed. Plumbers use rigid copper for indoor plumbing. Rigid copper pipes require connections. That increases the installation requirements and time. It also creates more failure points that you will need to maintain over time.
Copper vs. PEX: Temperature Resistance
PEX has a lower thermal conductivity than copper. This means that PEX is less prone to freezing. It is also more resistant to bursting if it does freeze. Copper can handle higher temperatures. But the upper threshold for PEX is 180 degrees Fahrenheit. Therefore, it is not a consideration in most scenarios.
Copper vs. PEX: Corrosion and Scale Buildup
Scale buildup and corrosion are among the top concerns with copper. Neither is a consideration with PEX. For these reasons, additional steps are necessary during installation of copper piping. These include minimizing velocities and hot water temperatures. You should have copper pipes inspected more often. In some cases, whole-home water filtration and/or softening systems will be necessary.
Copper vs. PEX: UV Resistance
PEX is susceptible to UV light and UV-A in particular. Building codes do not recommend it for outside usage because it can degrade quickly. Most codes do allow copper piping for outdoor usage but may specify the grade.
Copper vs. PEX: Chlorine
Chlorine in your water supply affects both copper and PEX piping. It can lead to corrosion in copper. Chlorine can lead to degradation in PEX. This has been one of the top concerns with PEX over the years. But there are a couple of points to consider. Manufacturing techniques have advanced. Most manufacturers add antioxidants to their PEX that fortify it against chlorine. Furthermore, most municipalities treat water with chloramine rather than chlorine. It does not have the same effect on PEX.
Copper vs. PEX: Pests
PEX is a plastic. Mice, rats, and even some insects can pierce it, which is much less likely with copper. That said, this is an uncommon event. In cases where it does occur, it is typically due to a pest problem that got out of control.
Copper vs. PEX: Sustainability
Many believe that copper is inherently more environmentally friendly because it is a natural material. This is not necessarily the case. Mining and processing copper have a greater negative environmental impact. Copper is recyclable whereas PEX is not, but the energy cost of recycling copper is high. Both copper and PEX tubing can be repurposed. Choosing PEX also lowers demand for copper. That results in more supply for applications where there is no viable alternative.
Copper vs. PEX: Resale Value
The real estate industry considers copper piping to have a positive effect on resale value. PEX piping has little to no effect in the current market. This is a positive change. In the 80s and 90s, it wasn’t uncommon for potential buyers to have concerns over long-term reliability.
Local Piping Experts in the Greater Sacramento Area
Consult with a professional to determine if PEX or copper is right for your home. Huft Home Services has more than a decade of experience. We have offices in Elk Grove, Sacramento, and Yuba City. Our approach to customer service and care earned us a Sacramento Winner award from the Sacramento Bee in 2023. We perform HVAC installations, maintenance, and repairs. Our plumbers not only re-pipe but clean drains and install tank and tankless water heaters, sump pumps, and water filtration systems. Our electricians upgrade panels and install indoor and outdoor lighting, surge protection, EV chargers, and ceiling fans. Contact us today to schedule an appointment or ask any further questions about the services and products we offer.
