As you browse through your local home improvement center, you’ll probably come across a section of colorful, coiled tubing. This flexible tubing, known as PEX, is a popular pick for plumbing systems. It’s a durable, flexible, and inexpensive option, making it a favorite of DIYers.
And the best part? It’s easy to install!
Key Points:
- PEX tubing is a flexible, durable, and cost-effective material that is rising in popularity among DIYers.
- Coloring the tubes based on purpose makes it easier to identify hot vs cold water lines.
- There are 3 types of PEX tubing – A, B, and C – that must meet performance standards for commercial and residential plumbing installations.
Before choosing a PEX tubing coil for your plumbing project, it’s essential to understand the differences between your options. This article explains these differences, so continue reading to learn more!
What Is PEX Tubing?
Cross-linked polyethylene tubing, better known as PEX tubing, is a staple in residential plumbing systems. The material was initially developed in Europe in 1968, but it didn’t make its way to the U.S. until the mid-’80s.
However, once it became a familiar face in the sea of plumbing materials, it rose to fame as a fan favorite. The material is flexible, making it much easier to handle and install than other plumbing materials, like copper or PVC pipe. On top of that, the material is surprisingly durable, making it a suitable choice for long-term installations. It even features a reasonable price, making it an excellent option for DIYers seeking a cost-effective plumbing material.
What Do The Different Colors Of PEX Tubing Mean?
PEX tubing comes in three standard colors: red, blue, and white. Plumbing code doesn’t require using specific colors for certain scenarios, but doing so can help. The colors don’t technically make a difference in the performance or application of the tubing.
That said, selecting tubing colors based on the application can be helpful, especially for identification purposes. Red PEX is usually associated with hot water lines, whereas blue is often used for cold water supply lines. You can use white PEX for either hot or cold lines.
Pairing tubing colors with the correlating temperature can make it much easier to quickly detect which water line you’re working with. This makes it much easier to contend with various situations, including emergencies.
Types Of PEX Tubing
There are three main types of PEX tubing: A, B, and C. They’re strikingly similar, sharing more similarities than differences. One of the primary differences between the trio is the manufacturing method:
- To make PEX A, manufacturers use the Peroxide or Engel method.
- With PEX B, the most common type available, manufacturers utilize the Silane or Moisture Cure method.
- To create PEX C, manufacturers employ Electronic Irradiation or Cold methods.
The letter accompanying the PEX label doesn’t indicate anything but the manufacturing method, as the grade is entirely separate from this label. Given the similarities between PEX tubing types, international plumbing codes recognize PEX in general instead of by type.
The umbrella approach to codes surrounding PEX tubing has everything to do with the similarities between the types, as they’re more similar than they are different. All of the tubing types must meet the same performance standards based on the application, as some requirements apply to commercial and residential plumbing installations. In contrast, others are specific to systems or applications.
Material Designation Code
PEX tubing also features a material designation code based on its level of chlorine resistance, UV resistance, and hydrostatic design basis (HDB, also known as a pressure rating). The code is a four-digit number, each number representing a different part.
The first digit represents chlorine resistance, with Class 5 as the highest available. The second digit represents UV resistance, with Class 3 (6-month UV resistance) as the highest available. Last, the third and fourth digits represent the HDB, like “06,” which indicates a 630 HDB or a pressure rating of 160psi at 73 F.
In addition to labeling based on manufacturing processes, PEX tubing is further divided by specific materials.
Non-Oxygen Barrier PEX
This type of PEX is common in most plumbing systems, particularly those carrying potable water to its destination. It comes in all three standard colors and varying diameters ranging from ¼ inch to 3 inches.
It’s available as PEX A, which is commonly used for kitchen and bath fixtures, as it’s incredibly flexible and offers the best freeze and kink resistance. In addition, it’s available as PEX B tubing, which is less flexible and freeze-resistant than PEX A.
Oxygen Barrier PEX
When non-oxygen barrier PEX isn’t a suitable choice, oxygen barrier PEX is another standard option. This option is commonly used for heating systems prone to rust and corrosion, like baseboard or radiant heating.
Like non-oxygen barrier PEX, this option is available in PEX A and B and in sizes ranging from ⅜-inch to ¾-inch.
Aluminum Barrier PEX
This three-layer type of PEX tubing features PEX, a thin layer of aluminum, and a second layer of PEX. Also known as PEX-AL-PEX, this tubing holds its shape after being bent into shape, eliminating the need to secure it every few feet.
The aluminum layer enclosed in layers of PEX acts as an oxygen barrier, so it can be used in similar scenarios as the oxygen barrier PEX. This makes it an excellent option for various situations, including warm board, outdoor, and high-temperature heating systems.
What Type Of PEX Is Best?
The best type of PEX varies based on factors specific to your project. For example, if you’re working with a kitchen or bathroom plumbing system, non-oxygen barrier PEX A is a strong choice. The material offers solid flexibility, freeze resistance, and kink resistance, making it a suitable option for kitchens and bathrooms.
Or, maybe you’re working with a radiant heating system. In this case, you could use the oxygen barrier PEX or aluminum barrier PEX as a suitable solution.
Ultimately, the best fit hinges on the application. If you’re unsure which option to use, research the best options based on the application. Alternatively, consult a local plumbing professional for advice.
What Type Of Fittings Work With PEX?
Given the widespread popularity of PEX tubing, there’s no shortage of PEX fittings to complete your project. There are push-fit, crimp, clamp, press, and compression fittings, some easier to work with than others. Brass push-fit fittings are one of the easiest varieties to work with, as they feature “teeth” that “bite” into the flexible tubing.
While you can use the other options, you’ll need specialized tools to get the job done. You can find these fittings, along with special tools, at various sellers, including online sites and home improvement stores like Home Depot, Ace Hardware, and Lowe’s.