Pex Tubing Chart

1. PEX tubing sizes are denoted by CTS (copper tubing size), not OD (Outside Diameter) or ID (Inside Diameter).
2. OD of PEX, copper and CPVC pipe with the same size (CTS) is the same. This is why push fittings can be used with all of these pipes.
3. PEX made to US standards must comply with a SDR-9 (Standard Dimension Ratio), which is the ratio of OD (Outside Diameter) to pipe wall thickness (9:1). Exceptions are nominal sizes 1/2″ and below.

Pressure Ratings

100 psi @ 180°F
160 psi @ 74°F

Pressure Testing

Required to ensure complete system integrity and leak-free performance. Test duration is generally no less than 2 hours. For heating systems, 40 psi minimum or at least x3 times the operating pressure is recommended. For hot & cold water plumbing systems, x1.5 is recommended. In both instances, the testing pressure should not exceed 100 psi. Slight variations in readings may occur due to natural expansion/contraction of PEX with temperature changes.

Typical water temperatures in floor hating applications

140°F for radiant floor heat applications in concrete, gypsum or other thermal mass slabs (both structural/reinforced and non-structural/non-reinforced).
160°F for installations of PEX under the subfloor between the joists. As low as 140°F with heat transfer plates. Consult with flooring manufacturer to ensure compatibility.
Up to 180°F for hydronic heating installations with baseboards or radiators.

This is the standard PEX type used in plumbing systems for hot and cold water distribution. Plumbing PEX tubing usually comes in red and blue colors to help installer distinguish between the hot and cold water piping. This type is not suitable for traditional closed-loop heating applications.

Has an external coating of EVOH polymer, which creates a barrier around the pipe, preventing permeation of oxygen into water through the pipes’ walls and prevents decomposition of cast iron elements and formation of rust. This type is used strictly for heating applications and is not suitable for potable water plumbing.

A composite type pipe comprised of 3 layers – PEX, aluminum and PEX bonded together. This is the only PEX type which exhibits “memory” properties and keeps the shape it was bent to. Smaller diameters can be used with pre-manufactured plywood panels; larger – for wood boiler and furnace lines.

One of the most important and distinctive advantages of PEX tubing over traditional copper plumbing is its cost. A typical 3/4″ size “L” type copper pipe runs today for about $2.00/ft, whereas PEX is less than $0.50/ft, which is a four times difference in price.

Unlike rigid copper, brass and CPVC pipes, PEX is flexible and requires a fraction of the quantity of fittings used in rigid pipe installations, which further reduces material costs, produces more pressure at the fixture and significantly cuts installation time.

Due to the nature of PEX piping, it expands and contracts more then copper and brass pipes and is able to absorb more thermal stress produced by changes in water temperature. As a result, PEX has more resistance to bursting from water freezing inside the pipes and eliminates the issue of “singing pipes”.

There are no good alternatives to PEX tubing in the radiant floor heating industry. Warm floor systems are more efficient than all other types of heating systems and produce the highest comfort level available.

In hydronic baseboard and radiator systems, PEX tube can easily replace copper pipes with less material costs and installation time.
While most PEX manufacturers only offer 20-25 year warranty, the expected lifespan of the pipe is estimated to be around 50 years, as long as it’s properly installed, kept away from sunlight and used within approved temperature and pressure ranges.

Everhot non-barrier PEX was and remains compliant with the “lead-free” regulations taking effect in 2014 and is NSF approved and certified for drinking water applications nationwide.