PEX Benefits & History
Before we learn about PEX Benefits and history, what is the PEX? PEX is a form of polyethylene with cross-links. It can be formed into tubing, and is used in building services pipework systems, heating and cooling systems, domestic water piping, and high voltage electrical cables. PEX is also used for natural gas and offshore oil application, chemical transportation, and transportation of sewage and slurries.
Recently, PEX has become the leading alternative to PVC, CPVC or copper tubing for use for residential water pipes. It ranges in size from imperial sizes of ¼ inches to 4 inches, but ½ inches, ¾ inches, and 1 inches are the most widely used. There are metric PEX available.
HISTORY
PEX tubing has widely replaced copper in plumbing application. One estimate states that residential use of PEX for delivering drinking water to home faucets has increased by 40% annually, and there is evidence that will become the dominant technology for carrying water in homes and businesses in the next decade. It is accepted by national organizations like the Habitat for Humanity for constructing homes.
In the 20th century, mass-produced plumbing pipers were made from galvanized steel. As a result, consumers experienced problems with the internal build-up of rust, which reduced water volume. These pipes were replaced with copper tubing in the late 1960’s. Plastic pipes with fittings using glue were used as well in later decades. Initially PEX tubing was the most popular way to transport water in hydronic radiant heating systems, and it was first used in hydronic systems in homes needing heat. Equipment such as baseboard heaters or radiators used PEX to recirculate hot water.
PEX became more accepted for indoor plumbing uses like carrying pressurized water to fixtures throughout the house. In the 2000’s, copper pipes as well as plastic PVC pipes are being replaced with PEX. It can be used for underground purposes as well.
PEX BENEFITS:
FLEXIBILITY:
It can bend into a wide-radius turn if space permits, or accommodate turns by using elbow joints.
DIRECT ROUTING OF PIPES:
PEX can run straight from a distribution point to an outlet fixture without cutting or splicing the pipe. This reduces the need for potentially weak and costly joints and reduces the drop in pressure due to turbulence induced at transitions.
GREATER WATER PRESSURE AT FIXTURES:
Since PEX pipes typically have fewer sharp turns, there is greater water pressure at the sinks and showers and toilets where it is needed.
LOWER MATERIALS COST:
Cost of materials is approximately 25% of alternatives.
EASIER INSTALLATION:
Installing PEX is much less labor-intensive than copper pipes, since there is no need to use torches to solder pipes together, or to use glue to attach pipes to fittings.
RELIABLE:
It neither corrodes nor develops so-called “pinhole” leaks.
NO FIRE RISK DURING INSTALLATION:
The oldest and most common method for joining copper piping is to solder pieces together using a torch. With an open flame there is always the risk of causing a fire in the surrounding structure, but PEX installation does not require a flame.
PLUMBER ACCEPTANCE:
There are routinely advertisements for plumbers specifically seeking ones with PEX experience
ABILITY TO MERGE NEW PEX WITH EXISTING COPPER AND PVC SYSTEMS:
Manufacturers make fittings allowing installers to join a copper pipe on one end with a PEX line at the other as well as giving options to reduce or expand the diameter of the pipes.
LONGEVITY:
The advantageous properties of PEX also make it a candidate for progressive replacement of metal and thermoplastic pipes, especially in long-life applications, because the expected lifetime of PEX pipes reaches 50 years.
SUITABLE FOR HOT & COLD PIPES:
A convenient arrangement is to use color-coding to lessen the possibility of confusion.
AVOIDS BURSTING FROM FREEZING:
The general position is that PEX plastic materials are slower to burst than copper or PVC pipes, but that they will burst eventually since freezing causes water to expand.
NO CORROSION:
Copper and iron pipes can experience corrosion leaks but PEX does not have these problems.
PIPE INSULATION POSSIBLE:
Conventional foam wrap insulation materials can be added to PEX piping to keep hot water hot, and cold water cold, and prevent freezing, if necessary.
Check out Mike Wilson Plumbing’s blog next week for more information on PEX fixtures, application and how it is used today in residential plumbing.