PEX Pipe Sizes & Dimensions | The Complete Guide

Greetings, esteemed readers; today, I am delighted to present an intricate guide detailing PEX pipe sizes and dimensions. This comprehensive resource is designed to facilitate the work of plumbing professionals and even DIY enthusiasts, rendering their tasks substantially simpler.

PEX Pipe Sizes and Dimensions 

PEX tubing is available in standard sizes from 1/4 to 3 inches per copper tube size (CTS) and in both inch and metric pipe dimensions. It’s characterized by a standard dimension ratio (SDR) of 9, with typical hydrostatic pressure tolerances of 160 psi at 73°F (1105 kPa at 23°C) and 100 psi at 180°F (690 kPa at 82°C).

Pex Pipe Size Chart 

The data below has been approximated as per ASTM standards. Sizes and dimensions are subject to manufacturing tolerances and may vary by brand.

Nominal Size (inches)Outer Diameter (OD) (inches)Wall Thickness (inches)Inner Diameter (ID) (inches)Weight per Foot (pounds)Maximum Pressure Rating (psi)

Interesting Read – ABS Pipe Sizes & Dimensions For Schedule 40 and 80

Salient Features of PEX Pipes 

Flexibility and Faster Installations

Of the several benefits of PEX pipe compared to other pipes, flexibility stands out. PEX pipes can easily maneuver and bend around corners without using any additional elbows and fittings.

This reduces material costs significantly because the pipings end up with fewer connection points eradicating potential leaks.

In addition, PEX pipes fit very well with coils up to 1,000 feet long, making them long-lasting.

Durability and Freeze Resistance

PEX resists scale buildups, which is a common phenomenon in copper pipes. PEX is also corrosion- and chlorine-resistant, which is another issue found in copper pipes.

PEX pipes can also work seamlessly in extremely high and low temperatures, making them useful in various applications.

The ability to expand and not become brittle during extreme freezing conditions makes PEX pipes less defenseless against bursts. However, it would be best if you still used standard installation precautions.

Peace of Mind

When plumbing PEX, there’s no need to use glue, solder, solvents, or torches. This keeps potential chemicals out of the plumbing system.

As there is no need to use additional tools, the chances of leaks, errors, and, most importantly, water damage are significantly reduced.

Other advantages include the following:

  • PEX pipes cost 25% less than copper. In addition, when piping your place with PEX, the piping company will charge you 0.40 to $0.50 per linear foot, whereas copper costs $3-$8 per linear foot. The overall cost difference between the two can save you a lot of money.
  • PEX is DIY-friendly, although not easy to work with; I’m sure determined DIYers will be able to make good use of it.
  • PEX provides a main shutoff, meaning each pipe has its valve shutoff at the manifold. The manifold is generally located where the water main enters the house. Labels are placed in the last shutoff valve-like “bathtub” or “kitchen sink.” That makes repiping easier when needed because you won’t have to shut off all water, only the water you’re willing to fix.
  • PEX pipes are good at minimizing water flow sound, which is rarely found in a copper piping system.
  • PEX pipe sizes and dimensions are categorized so that a professional plumber would have no problem installing fittings related to the plumbing.

Engaging Read – What is PVC Fittings? | What is PVC Connection? | The Definitive Guide

Disadvantages of PEX Pipes 

Although PEX’s pros far outweigh the cons, discussing them is essential. Here are a few cons of the PEX pipes.

  • PEX is extremely sensitive to UV light. The experts always recommend no exposure to limited exposure to sunlight during installation.
  • Chemicals and pests readily attack PEX. One more unusual problem has also been noted with PEX: mice chewing away your pipe, which is impossible with copper or metal pipes. Although, this is more of a rodent problem than a pipe problem.
  • PEX is semi-permeable, meaning liquid can enter the pipe. As far as safety is concerned, PEX isn’t anti-bacterial. Liquid interfering in the pipe can lead to contamination.

PEX Pipes Applications 

  • Portable distribution systems or water supply lines.
  • Residential fire/sprinkle systems.
  • Radiant floor heat applications.
  • Water distribution in applications where hot water is involved, including radiators.
  • Heat transfer applications like snow melting, floor cooling, and permafrost protection.

Labeling on PEX Pipes 

PEX pipes are manufactured and categorized by their outside diameter dimension, which is called copper tube size (CTS). PEX pipes should be labeled every five feet with the information mentioned as follows:

  • Pipe manufacturer’s name or trademark
  • Pipe standard – (ASTM F876, F877, AWWA C904 or CSA B137.5).
  • Tube size and copper tube size (CTS)
  • Pipe-specified pressure/temperature ratings
  • Plumbing pipe designation code
  • SDR9 (Standard Dimension Ratio is a ratio of the pipe’s diameter to the wall thickness of the pipe) is Generally used by manufacturers to rate pressure piping.
  • Pipe manufactured for potable water must be labeled for that application.
  • ASTM fittings designations are approved for use by the pipe manufacturer.

Fascinating Read – PVC Pipes: Sch 40 Pipe Dimensions


Below are the frequently asked questions for PEX sizes. Let’s dig deep to know more.

How many fixtures are on a 1/2 PEX water line?

1/2 inch PEX pipe usually has up to 4 fixtures. 3/4 pipes can have up to 14 fixtures, and 1-inch pipe can have up to 30 fixture units.

How far apart should PEX hangers be?

Proper hangers must support long runs of PEX pipe. It is usually recommended to fasten the tubing every 32 inches alongside a joist and at least every 6 feet if the tubing is supported by beams and running across them.

Does PEX need expansion loops?

Remember that PEX expands and contracts as a response to the surrounding temperature. For every 10 F of temperature change, the PEX pipe length is changed by 1 inch/100 feet of piping and 1 inch/100 feet of piping. For longer runs adding loops is a great option to provide further slack.

What is the maximum distance between hangers for 1/2 PEX?

Maximum hanger spacing is 6′ for ½” and ¾” pipe and 8′ for 1″ and larger full-length pipe segments with PEX-a Pipe Support.

Is PEX safe for drinking water?

PEX pipes are 100% safe to be used for drinking water. A few PEX pipes may cause prolonged undesirable taste and odor if the water remains in the pipes over time, but that issue must be discussed with the plumbing company beforehand.

Does PEX piping affect the water pressure?

No. The PEX piping doesn’t slow or affect the water pressure anyway.

Suggested Read 

The Takeaway 

That’s all I want to say about PEX pipe sizes and PEX pipe dimensions. Anyway, always consult with your plumbing company related to the specific need you have with your plumbing to get the bt results in the end. For residential usage, I believe PEX pipes be a fantastic choice. PEX pipes stand toe-to-toe with the more popular counterparts like PVC, CPVC, and copper.

Thanks for reading. Have a lovely day ahead.

4 thoughts on “PEX Pipe Sizes & Dimensions | The Complete Guide”

  1. “Does PEX piping affect the water pressure?
    No. The PEX piping doesn’t slow or affect the water pressure anyway.”

    I disagree, while the inside diameter is only slightly smaller than its copper equivalent (.681 to .75”) the fittings are considerably smaller and do impact pressure. Especially when there are several T fittings in the trunk line between the service and the faucet.

    • Pex is much more restrictive than hoses would be. Especially once you add on a silencer kit and tank to quiet the ridiculous noise a pex systems makes. If I did it over I would use 3/4 potable water/garden hoses throughout the entire rig. And I still may. I like a nice strong shower and a good spray for washing dishes. I have an oversized pump designed for a 60 foot yacht to force enough pressure through the pex system just get by for now. It’s 20psi over the rating of the pex but i’ve only had a couple small leaks. With 25′ light duty hoses on sale at WM for $13 maybe I’ll tackle it sooner than later IMO a proper hose type clamp (with the rounded edges) is more effective than the set it and forget it PEX clamps.


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