Pex Plumbing is a type of plastic tubing used in both plumbing and heating applications. PEX stands for cross-linked polyethylene. Pex Plumbing has been installed in Europe for over 30 years, and its use has become widespread in the United States over the last 10 to 15 years. Because of its ease of installation, reliability, and relatively low cost, Pex Plumbing is continuously growing in popularity. It is more flexible, stands up to freezing better, and is less expensive than copper and CPVC pipe.
Types of PEX
PEX is manufactured in three different grades: PEX-a, PEX-b, and PEX-c. Each differs in the way it is produced: PEX-a is made using the Engel method and is the strongest, most uniform, and most flexible out of the three. PEX-b is made using the Silane method and has the same properties as PEX-a after installation. PEX-c is made using the electronic beam method, which is the most environmentally friendly method out of the three.
PEX is great for use in hydronic or radiant heat systems, withstanding temperatures as high as 200 degrees. PEX tubing is widely used as an alternative to copper piping in plumbing systems. To differentiate between hot and cold lines, PEX comes in red and blue colors. PEX for heating typically contains an oxygen barrier to prevent the rusting of ferrous system components.
Pex Pluming is available in sizes ranging from 1/4″ to 4″ (1/2″ and 3/4″ are the most common), with larger-sized tubing becoming more popular as the fittings and tools have become more readily available. PEX also comes in coils ranging from 100′ to 2000′ and comes in straight lengths generally between 10′ and 20′. Additionally, PEX can be buried in a slab or underground, making it extremely versatile and adaptable.
Manifolds are common additions to PEX systems, functioning as the “hub” or centralized location for all of the PEX lines. In radiant heat systems, manifolds act as the distribution points from which loops run. In plumbing systems, there may be one centralized manifold (known as a “Home Run system”) or multiple smaller manifolds distributed throughout the residence.
There are several different PEX fitting and tool systems: crimp/clamp, expander, press, and compression. Perhaps the most widely used system is the crimp or clamp system, which utilizes barbed fittings with copper crimp rings or stainless steel clamps. The system most widely used by professionals is the Uponor expander system.
The Uponor expander system for connecting PEX uses an expander tool alongside specialized ProPEX fittings. Another popular PEX system amongst trade professionals is Viega’s press system. The PEX press system uses press fittings, sleeves, and a PEX press tool. Finally compression fittings, such as Sharkbite fittings, make fast and easy PEX connections.