Crosslinked polyethylene, or PEX, has several characteristics that might make it a superior material for plumbing lines when compared to options such as traditional copper pipe or hard plastics. While the other plumbing options are rigid, PEX is a flexible tubing that can be installed more easily. It is also a durable material, and is designed to outlast an equivalent line made of other materials.
In northern climates, water pipes can be subject to damage by freezing. Both rigid plastic and metal pipes can freeze and burst. While this could happen in severe temperatures with PEX, it is much less likely. This helps prolong the life of the material in any location where the water pipes regularly face extreme temperatures in the winter, according to Pexinfo.com.
Copper pipes are vulnerable to certain types of corrosion. Often this is due to the characteristics of the water being provided to the supply line. If it is particularly acidic, it speeds the corrosion process of the copper pipes. Other types of pipes are even more vulnerable to this. However, PEX lines don't typically corrode and shouldn't degrade no matter what the quality of the water in the line.
PEX has other advantages that combine with its primary strengths to make it a long-lasting material. Unlike other types of pipe, PEX does not encourage buildup of lime or other minerals, according to Zurn.com. This helps keep the pipe functional for a longer period. The flexibility of the material is also helpful. Sometimes, plumbing pipes are placed in tight quarters and as a house settles or shifts, this can sometimes put pressure on pipes that causes damage. Flexible pipes are much less prone to outside pressure damage than rigid pipes.
PEX has been in use in Europe for more than 20 years, as of the date of publication. However, testing in the industry shows that PEX should last much longer than 20 years. According to Comfortcontrolsystems.com, PEX pipes that aren't damaged by external factors should last at least 70 years. In many cases, this means that PEX pipes are going to last for the lifetime of the building that they are installed in.