How Long Does PEX Pipe Last?

PEX pipe has grown rapidly in popularity among both homeowners and contractors over the past two decades, and for good reason. A mainstay in Europe since the 1980s, PEX made its way across the pond a little later, but is now used everywhere and by everyone.

What makes PEX pipes so great, however, what are their pros and cons, and how long do PEX pipe installations last? Let’s explore all the details below.

What is PEX Pipe?

PEX pipe or PEX pipe is a type of plastic pipe similar to PVC pipe and CPVC pipe, but with a slightly different composition. Made of cross-linked polyethylene, hence the name PEX, these pipes were the first invented in 1968 by German scientist Thomas Engel who found a way to bond ordinary polyethylene (plastic) with radiation to make it much more flexible.

Shortly after its discovery, PEX pipes began to make their way into construction work in Europe in the 1980s, especially in radiant floor heating systems – these are systems where PEX pipes run through the center of concrete slabs and I warm them with hot running water. through pipes.

PEX pipe is popular in radiant heating systems to this day, but it took a while after the 1980s for this plastic pipe to be used for anything else, especially in the US. This is because the previous version of PEX tubing used to deteriorate quite quickly when exposed to high chlorine content in the water.

What is PEX Pipe?

This meant that a slight plastic taste would start to be noticeable when PEX pipes were used for water supply lines in the US, as chlorine levels in US water are higher than in Europe. This was obviously unacceptable, so PEX remained rarely used outside of heating for a while.

All this changed when the manufacturing process of PEX pipe was improved with adding antioxidants to PEX. This helped PEX pipes handle chloride without deterioration, and now PEX pipes are used in the US as well as Europe as water lines in showers, sinks, tubs and other plumbing fixtures.

But does this mean that PEX pipe is a suitable substitute for other types of pipe, or do they have other disadvantages? Should you replace your copper or steel drain with PEX pipe the next time you do repairs or not? To find out, let’s first go over a few different types of PEX pipe and their individual specifications.

Types of PEX Pipe

There are three main types of PEX tubing with the differences between them depending on the exact way in which they were manufactured. There are several other subtypes, usually color-coded depending on whether the pipe is intended for hot or cold water lines. Let’s go over the 3 basic types first though:

1. PEX-A pipes

This type of PEX is made using peroxide in the manufacturing process. This makes PEX-A the most flexible type of PEX and therefore this type of PEX is ideal for most in-wall plumbing that requires lots of twists and turns without extra connectors and joints.

PEX-A is also the best type of PEX in terms of expansion and contraction with freezing water temperatures. In other words, PEX-A pipes have the best durability in cold temperatures and have the least risk of cracks and leaks. Therefore, PEX-A pipes are the most expensive type and are about x2 more expensive than the next two types.

2. PEX-B pipes

PEX-B tubing is created using a moisture curing method that also gives it impressive flexibility, but not as much as PEX-A. Unlike their more expensive counterparts, PEX-B pipes have a noticeable «coil memory», which means that the pipes will continue to try to coil during the installation process. This is rarely a problem, however, because once they are put in place properly, they will stay there.

In terms of expansion when the water is near freezing, PEX-B pipe is still pipe material, but not quite to the level of PEX-A. This second type is usually the preferred choice plumbers for PEX sanitary installations as they are good enough for the jobs they are needed for, but are noticeably more affordable than the PEX-A type.

3. PEX-C pipes

The last and most affordable main type of PEX plumbing is PEX-C pipe. These pipes are manufactured using an irradiation method, which means they are not as flexible as PEX A and B pipes. Essentially – they are quite rigid, which is not ideal as the pipe will need to do turns in the installation. This stiffness also means that PEX-C pipes are at greater risk of cracking with cold water flowing through them.

At the same time, PEX-C pipes are also about 2 times more affordable than PEX-A pipes. So if you know the pipes won’t have to operate in near-freezing temperatures and won’t have to make any twists, you can save some money with this type of PEX.

Other types of PEX pipe

Other types of PEX pipe

In addition to the manufacturing process and the corresponding type—which should always be listed on the label—PEX pipes are also color-coded according to the type of use they are intended for. There are 4 main colors you will come across:

  • Red PEX pipes – for hot water
  • Blue PEX pipes – for cold water
  • White and gray PEX pipes – can be used for both hot and cold water

The difference between these 4 colors is in certain additional components that make them more suitable for either warm or cold water.

How long does PEX pipe last?

So, how long does PEX pipe last?, depending on the type? Well, the good news is that almost all PEX pipes have an estimated lifespan of up to 50 years with good maintenance, almost regardless of their type.

Arguably, PEX-A has a longer lifespan due to less risk of cracking, but PEX-C piping is not meant to be used with freezing water anyway, so it wouldn’t qualify as «good maintenance» anyway .

Depending on the type and manufacturer, you can expect to get a 10-year warranty, but that doesn’t mean the pipes will deteriorate after that. If properly installed and used for their intended purpose, they can last as long as copper pipes.

Advantages and Disadvantages of PEX Pipe

So, to determine how PEX pipe compares to copper pipe and other types of metal and plastic pipe, let’s explore their pros and cons:

Pro:

1. PEX pipes are resistant to mineral build-up from hard water

Regular copper pipes are very vulnerable to mineral build-up such as electrolysis and scale inside the pipes. This is not a problem with PEX pipe.

2. They do not include toxic chemicals such as BPA

Unlike ABS pipes and like PVC pipes, PEX does not include BPA. Certain animal studies have shown that BPA has negative health effects, even though it is considered ok by most regulatory authorities.

3. They are very flexible and often do not need header joints, connectors, etc

The big problem with installing metal pipes and other rigid pipes is that you have to add joints and connectors at every bend – this is much less of a problem with PEX because these pipes are flexible enough to turn 90 degrees and not requires joins. This does both the installation process much easier and reduces the risk of leaks.

4. PEX is more resistant to frost cracking than copper and the steel

As PEX expands at low temperatures, it is highly resistant to freeze cracking – something that cannot be said for metal pipes.

5. PEX is corrosion resistant

This is a benefit common to all non-metallic pipes, and PEX is no exception.

6. Can be connected to existing metal systems

Another factor that makes PEX great for repairs is that you can just repair a broken section of copper or galvanized steel with PEX and leave the rest of the metal pipe there too.

Advantages and Disadvantages of PEX Pipe

Versus:

1. Lack of resistance to UV light

One of the big downsides you always have to consider is that PEX pipes deteriorate quickly with exposure to UV light. They are similar to ABS pipes in this respect and different from PVC pipes which can withstand sunlight without problems.

2. Can be easily destroyed by rodents

Direct physical damage is another some disadvantages of PEX. If there are rodents such as rats in your area, thin plastic pipes can easily break or at least leak from rodent bites and other physical damage.

3. Chloride resistance may be temporary

Are studies that show that the antioxidants added to PEX to make it resistant to the high chloride content of the water may not have such a long life. This is because the antioxidants added to PEX tubing during the manufacturing process are considered to be «sacrificial,» meaning their amount in PEX decreases with increasing exposure to chloride.

So, such studies show that certain compounds can still begin to leach into people’s drinking water from PEX pipes after several years of heavy chloride exposure. That’s why some specialists recommend that PEX pipes should not be used for potable water pipes even though the general consensus these days is that they are good enough for that.

Bottom line – how long does PEX pipe last?

Whether you are doing renovations or new construction, PEX pipes seem to be a good choice for most jobs in a plumbing system.

Outside of areas where they would be exposed to direct sunlight, PEX pipe is easy to install, affordable, and has a very long lifespan of several decades and up to half a century. So they definitely seem worth considering for your building or remodeling project.