Copper Pipe vs PEX: Which is Better?

While copper pipe and PEX are common pipe materials, they have several advantages and disadvantages that make one better depending on the situation.

Copper pipe is better for long term use and you can use it above ground or in areas exposed to UV light. It has a much longer history and allows you to use fewer fittings.

PEX is significantly cheaper than copper. PEX pipe is a younger technology, so we know less about the potential harm. Works best for DIY projects, heat preservation and areas known to freeze and thaw quickly.

If you want to know which one is best for your project, please read on to get more information!

Copper pipe bases

Copper pipe comes from copper raw material mined from the ground. This mineral is either melted or heated, then cast into molds to obtain the tube shape.

While copper has a long history of useit has recently resurfaced to replace other metal pipes found to contaminate water with lead and other harmful materials.

Copper pipes are known for their durability. Although they may require more basic knowledge to use, learning how to work with copper tubing pays off.

Copper pipe bases

The basics of PEX

The process of making PEX pipe and tubing is less straightforward. In short, high density polyethylene (HDPE) is heated using the Engel method to bond the chains of ethylene molecules. This gives PEX its unique characteristics.

PEX pipes are chemically stable, quite strong, and incredibly flexible. While PEX started with radiant heating, it is now a major contender for plumbing applications.

PEX pipes have several advantages over copper pipes, including ease of use and low cost. The two may compete in some areas, but each material has situations where it is more suitable.

Copper pipe vs. PEX: What’s the difference?

Both copper and PEX pipes are common choices for water supply pipes, but they differ in:

  • History
  • Lifespan and durability
  • Varieties available
  • Potential dangers
  • Higher usage
  • Cost
  • Durability
  • Installation method
  • Appropriate temperatures

These differences are what make them very different products and help you determine which one works better depending on the scope of your project.

1. History

Copper plumbing dates back to ancient Egypt and acted as the main conduit for water distribution in North America until the early 1960s. This material has a much longer history than PEX, which means we know more about its pros and cons .

Copper remains a durable material used in many homes, but it is not the only one.

German scientist Thomas Engel developed PEX in 1968, almost 4 decades after it was formulated and removed. Due to its application as continuous pipes, durability and light weight, it exploded in Europe in the 1980s.

North America took longer to adopt the material because the chlorine used to purify water in many regions would damage the pipe. PEX was still used in underfloor heating systems until modifications to the plastic strengthened it against chlorine failure.

PEX is now one of the most popular choices for water supply lines in both residential and commercial buildings around the world.

2. Lifetime and Durability

The lifespan of both copper pipe and PEX pipe is debatable, but copper tends to last longer with proper care. Expect a lifespan of over 100 years for copper and about 50 years max with PEX.

The durability of each pipe depends on a number of factors, many of which we will expand on later. PEX tends to degrade Fastereven under proper conditions, while copper failures such as hole leaks can occur much earlier than they would in PEX and can be more difficult to correct.

Copper pipe is tough, so it won’t fail from pressure or rodent gnawing like PEX. They do not deteriorate when exposed to UV rays and are completely waterproof and work well both above and below ground.

Lifespan and durability

PEX will have no corrosion problems in hard water conditions and is less susceptible to problems from:

  • Water based chemicals
  • Electrolysis
  • Freezing temperatures

The actual life and durability of the pipe depends on its exact type, but copper usually lasts longer as a general rule.

3. Varieties

While copper pipe and PEX pipe have different compositions, they also come in different varieties to suit different situations.

Varieties of copper

Copper pipes are available in four types when used for the transport of liquids or gases. You can identify the pipe by looking for a K, L, M or DWM or corresponding color code on it.

  • Type K (Green): Thickest walls; more durable, but also difficult to use and expensive. Common with ground water mains, fire sprinkler systems, commercial plumbing, industrial facilities and heating, ventilation and cooling systems.
  • Type L (Blue): Often used in hard water areas to combat the effects of corrosion; common for repairs to copper pipes, interior water lines, fire sprinklers, and heating and cooling systems.
  • Type M (Red): Slim but still works for water delivery; lighter and therefore less expensive, but used for indoor residential water supply lines (less concern for water pressure or chemicals).
  • Type DWV (yellow): drain, exhaust and exhaust pipes; pipes of larger sizes and rather thin walls unsuitable for current pressure standards; most common in older homes.

Varieties of PEX

Varieties of PEX

Like copper pipes, there is four types of PEX pipe. These types differ in how they are manufactured, including the additives that determine their applicable use.

Although there are many brands of PEX on the market, most follow the same standard for labeling pipes properly. PEX typing is all about additives and manufacturing, but different brands carry distinct qualities and grades.

  • PEX A: Made with peroxide added before extrusion. The most flexible type, cracked and resistant to relatives. Thermal memory and low density ensure return to original size after expansion.
  • PEX B: Moves through a stream of silane after the extrusion process. The most resistant to oxidation and chlorine. Less expensive and stiffer than Type A.
  • PEX C: Exposure to electron beam during production. The least expensive type, but the most likely to break or bend. Mainly used for shorter connections or repairs.
  • PEX-AL-PEX: Made with aluminum between layers of PEX that allow it to hold its shape and prevent collapse. The most expensive guy. Often used in radiant heating systems.

PEX pipe comes in a variety of lengths, ranging from 10 feet to 500 foot rolls. Different colors usually help identify the use of the pipe: blue for water, red for hot lines, and white for miscellaneous lines.

4. Potential Hazards

Both materials have certain concerns, including the potential to damage the environment or poison the water supply.

Copper has a longer history of use and observation and has yet to cause major problems. Although it is rare, high copper levels are linked to:

  • Nausea
  • Vomiting
  • Diarrhea
  • Gastric problems
  • Headaches

Long-term exposure usually comes from unresolved issues in a compromised copper line and can lead to liver damage and (rarely) death.

Beyond these concerns, copper is antimicrobial and is commonly used to purify water sources.

PEX has a much shorter history of research, and the different brands of PEX production obscure the results of any related research. PEX is more susceptible to contamination than copper.

A study 2021 evaluated water from 8 different brands of PEX and found a total of 62 chemicals leached into the water they transported. Of these, about half are considered toxic (but not carcinogenic).

More testing of PEX is needed to accurately determine potential hazards, as current published work does not account for various factors, such as PEX fittings, or does not show a clear picture of PEX as a whole.

5. Higher usage

Because copper pipe and PEX they have different characteristicsthey are more suitable for different tasks.

Copper works well both underground and above ground, and you can use it for water or gas distribution. You will often see chilled water piping with copper piping, as well as drainage and ventilation systems, fuel and oil systems, oxygen systems, non-flammable medical gas systems, and certain heating systems. (including solar).

PEX maximizes its flexibility and efficiency. Although it is also used for water supply lines, you also see it in radiant floor heating or cooling systems, snow melting applications, residential fire sprinkler systems, and as a water distribution line for hot water applications.

6. Cost

Copper pipe costs 3 times the PEX pipe of the same length.

When comparing 10 feet of ½ inch pipe, the prices look like:

Prices vary by location and the current price of materials, but copper will always be more expensive than PEX. Although you can sell copper pipes to recoup your costs eventually, this does not offset the expense.

7. Sustainability

Copper is immediately more natural than PEX, but it must be:

  • extract
  • Heated or melted to a pure state
  • Pour into a pipe shape

Copper mining and manufacturing is more negative than PEX production, but it is fully recyclable and promotes sustainable practices.

PEX is derived from petroleum-based materials, and production requires:

  • Extraction of natural gas or oil
  • Transport to a refinery
  • Distillation
  • Chemical and mechanical manipulation to create PEX

While the process may be less impactful than copper mining, PEX can only be reused. Burning releases toxic fumes.

Durability

8. Installation

Copper requires more work to install, including special bending and brazing methods for joints and fittings.

PEX, which is lighter and more flexible, is much simpler to install. Because the tubes are flexible, there’s no worry about fittings or expertise, and you don’t need special tools for cutting or adjustments.

PEX requires more support in the form of brackets and clamps, but fewer joints reduce the chances of leaks in these areas.

9. Appropriate temperatures

Copper acts as a conductor, making it less effective at extreme temperatures. Copper reduces the efficiency of hot water heaters by extracting heat from the water. They are more likely to break if the water they carry freezes.

PEX should be kept away from high temperatures, but transfers water more efficiently from a hot water heater when installed after 18 inches of copper from the water heater. PEX also expands to accommodate freezing at lower temperatures and easily returns to its original size.

Conclusion

The PEX vs copper pipe debate does not result in a cut and dry answer. In most cases, it depends on your budget and what you need the pipes for.

Professional plumbers understand which material works best in different situations, and homeowners benefit from sharing that understanding. While there are plenty of gray areas where you can use copper or PEX piping, make sure there’s no reason to avoid a particular material for your project.

Comment below with any questions or observations you have about the copper vs. copper debate. PEX.