PEX tubing types - Oxygen Barrier vs. Non-Barrier

PEX tubing types - Oxygen Barrier vs. Non-Barrier

One of the most common questions you face when starting on a plumbing or radiant heating project is whether to choose PEX tubing with oxygen barrier or non-barrier.

The main difference between the two types is the external polymer coating of the oxygen barrier PEX tubing, which makes the tubing prone to oxygen diffusion. Oxygen barrier PEX is used in radiant or hydronic heating applications only, where cast iron or other ferrous components are present in the system. Since contact of oxygen molecules in the water with ferrous parts in the system results in rust, oxygen barrier helps to prevent ferrous components from corrosion.

Oxygen barrier is also called EVOH (Ethylene Vinyl Alcohol), which is simply the abbreviation for the polymer.

DIN 4726 is the standard that can commonly be found imprinted of the oxygen barrier PEX tubing and shows that the oxygen diffusion barrier requirements are met.

Non-barrier PEX tubing, or simply PEX plumbing tubing is used for plumbing applications. Since there's always a supply of fresh water from a water heater or a water main, oxygen molecules will always be present in the system, so there's no need for the oxygen barrier.

If you already have the tubing but don't know which one you have, bring it to the light and take a closer look. If the tubing has a shiny surface - it's PEX with oxygen barrier; if the surface is matte - it's non-barrier PEX. Most manufacturers also have the type of PEX imprinted on the pipe. Don't get confused with colors, as they do not idicate the type of tubing, they are used for color coding purposes only.

PEX Tubing with Oxygen Barrier

PEX Plumbing Tubing (Non-Barrier)

The following was added to your shopping cart: X

Forgot Your Password?

Enter your e-mail address below.
You will receive an e-mail
with password reset instructions.