PEX Plumbing Pipe
PEX or Cross-linked Polyethylene is a plastic material used as a water supply piping systems that provides several advantages over copper, iron, lead, or PVC plumbing pipes. PEX pipes as excellent properties such as superior heat resistance, long term durability and is an excellent plumbing solution for fire-sprinkler systems. PEX plumbing pipes should meet ASTM F876, ASTM F877, AWWA C904 and/or CSA B137.5. PEX pipe ranges in sizes from ¼ inch to 4 inches, but 1/2-inch, 3/4-inch, and 1-inch are the most commonly used pipe sizes. PEX is now, one of the most innovative materials being used for water distribution systems, and its use has increase by 35% annually, and it’s still growing. PEX will become the dominant plumbing pipe in the near future.
PEX Plumbing Pipe Advantages
PEX plumbing pipe can offer several advantages such as:
- PEX is much more resistant to freeze-breakage than copper or rigid plastic pipe.
- PEX pipes conserves energy, by reducing heat transfer
- PEX pipe eliminates the ‘water hammer’ noise usually found in copper pipe systems.
- PEX is shipped in spools, reducing shipping costs
- Its flexible characteristic provides additional storage options.
- It is available in various lengths and dimensions.
- Doesn’t corrode over time
- As opposed to copper pipe, PEX will resist the scale build-up
- PEX tube to fittings does not require soldering
- Reduced number of connection and fittings, decreasing also the probability of water leakage. The flexible piping can be installed at 90 degree corners without the need for elbow fittings.
- PEX plumbing pipes are installed faster than any other plumbing pipe
- Provide resistant to scale and chlorine
- PEX pipes are flexible
- PEX is less expensive than copper pipe.
- PEX tubing is accepted as a water distribution pipe in all major plumbing codes.
PEX Plumbing Pipe Applications
PEX plumbing pipe has been used for several decades in European countries and have been introduced to the United States over a decade. PEX pipes could be used for:
- PEX is widely used for plumbing and radiant floor heating applications.
- PEX can be used as water service lines or potable distribution systems.
- PEX tubing is also widely used for heat transfer applications such as floor cooling, snow melting and permafrost protection.
- Could be used to distribute water for hot water applications, including radiators.
- PEX is approved for use in residential fire-sprinkler systems.
PEX Plumbing Pipe Restrictions
PEX plumbing pipe, although offers many advantages, it must also be treated carefully. PEX could be limited to:
- PEX must not be in contact with direct flame
- PEX should be kept away or covered from receiving direct or indirect UV light
- PEX could be damaged if exposed to high chlorine concentrations.
- Avoid using PEX if it’s going to be installed in contaminated soils.
- Pipe thread compounds, mineral or oil-based products should not be used with the pipe as these materials could alter the pipe’s characteristics or damage pipe fittings.
- Installing the pipe near hazardous waste disposal sites or petroleum storage tanks is not recommended.
- PEX fittings, particularly compression ones, are more expensive than copper fittings.
PEX Plumbing Pipe Identification
PEX tubing is manufactured and classified by its outside diameter dimension, commonly called copper tube size (CTS). PEX pipes should be labeled, at least every five feet, with the following:
- Pipe’s manufacturer name or trademark
- PEX pipe standard to which it conforms (ASTM F876, F877, AWWA C904 and/or CSA B137.5)
- Tube size and copper tube size
- Plumbing pipe designation code (PEX0006 or similar)
- Pipe specified pressure/temperature rating(s)
- If the pipe is intended for potable water, it must be marked for suitability
- ASTM fittings designations approved for use by the pipe manufacturer