Easily Complete DIY RV Plumbing Repairs With A PEX Crimping Tool

We used to think repairing PEX plumbing was difficult, so we avoided taking on projects involving PEX. But, it turns out it’s not hard to do at all. With the right tools, it can be a simple and rewarding DIY repair or upgrade project. Even though PEX tools are specialized, they’re both inexpensive and readily available at a local store (hardware, home improvement, etc) or online.

One of those special tools is a PEX crimp (or crimping) tool. In this post, we explain why this unique tool will make working with PEX a whole lot smoother and easier. We also share a few other tools to keep on hand so you can work with PEX in your RV (or your sticks & bricks house, if you have one of those, too!).

What Is PEX?

PEX, an acronym for cross-linked polyethylene, is a flexible type of plastic tubing used in modern plumbing systems, including on RVs. Its flexibility and ease of use make it a perfect match for those who prefer a DIY approach to plumbing repair and upgrade projects.

PEX has been the most popular pipe choice in Europe for decades, but the higher chlorine content of U.S. water raised concerns about its use that needed to be addressed. Since PEX has been further developed to meet U.S. requirements, it’s become a popular plumbing solution for DIYers and professional plumbers alike.

What’s So Great About PEX?

There are several benefits to using PEX tubing for plumbing, as opposed to copper or other options. That’s why PEX is used in more than 60% of water supply systems in the new construction of residential buildings… as well as in RVs.

1. More Sustainable Option: Although copper and other plastic pipe types were the standard for many decades, PEX is a simpler, more sustainable choice. The mining, manufacturing, and shipping processes, along with the weight of copper pipes, make them less environmentally friendly. Copper is also a good conductor of heat, which wastes the energy required to heat water — copper pipes cool the water en route from the heater to the faucets. While PEX is also a non-natural material with a less-than-zero impact on the planet, it’s considerably less than other (common) options.
2. PEX Doesn’t Corrode: Unlike other piping materials, crosslinked polyethylene (PEX) won’t corrode. PEX pipe is durable and isn’t affected by mineral buildup, corrosion, or even the process of electrolysis, which can eventually cause tiny pinhole leaks in copper pipes.
3. PEX Costs Less: PEX is about one-third the cost of copper… a significant savings. And the cost of PEX doesn’t fluctuate daily as the cost of copper and other metals does.
4. PEX is Flexible: PEX is available in a variety of sizes, from ¼-inch to 4-inch. The pipes are flexible because they’re constructed from a plastic material rather than rigid metal. Flexibility is a big benefit because you can bend it around corners. This means buying fewer parts in some situations because the need for 45-degree or 90-degree elbows is reduced.
5. No Need to Solder: Here’s a huge benefit of PEX over copper – there’s no need to solder! This makes PEX more DIY-friendly, and even if you’re hiring a professional plumber, your labor costs will be lower due to the elimination of soldering.
6. Less Likely to Burst or Split: And finally, PEX pipe is less likely to burst in freezing conditions than metal pipes. It can freeze, but PEX isn’t likely to burst because it’s flexible, so it’s more likely to expand rather than split.

Does Working with PEX Require Special Tools?

Yes, buying a couple of tools specifically for the purpose of working with PEX is necessary. But they’re not expensive or difficult to use! And, once you buy the tools, you’re prepared to take on future plumbing repairs and installations.

There are a couple of important things to consider when working with PEX:

A Clean Cut

First, you need a clean, straight (90-degree) cut in the PEX line to prepare it for attaching to the joint or fitting. For this, you should really use a PEX pipe cutter, which is super inexpensive and super easy to use, perfectly, every time.

IWISS iCrimp PEX Pipe Cutters Tool for Cutting 1/8"-1" PEX Tubings, NOT for PVC Pipes

• Pex Cutting Tool: Cuts PEX Pipes from 1/8" to 1"
• Capacity:PPR PEX A pipe cutter is an easy to use, great value cutting tool to handle cutting 1/8 in., 1/4 in., 3/8 in., 1/2 in., 3/4 in., and 1 in...

$7.85

Buy on Amazon Price & availability info updated 2026-05-15 at 12:47.

A Solid, Tight Clamp

Second, you need to be sure that you create tight connections. To do that, you need to be able to squeeze special PEX clamp rings into place so that they’re properly and tightly clamped for a solid, durable connection. So, you’ll need a PEX crimp tool (or “cinch” tool). This ensures the clamps are completely tightened onto the fitting.

Note that there are two types of rings. One is a smooth circle, and the other is circular with an “ear” that sticks up on one side (which is the type we prefer). There are also two types of PEX cinch tools — ratcheting and non-ratcheting types. We only use the ratcheting type, since they’re virtually fool-proof. They’re also smaller, which makes them easier to use in the typically tight confines of an RV.

The special tool that crimps/clamps the PEX ring “ears” into place is fantastic. It’s not only easy to use, but the ratcheting device makes it practically impossible to cinch the rings too tight or too loose! That’s because once you begin clamping down on the ring, the tool ratchets/clicks as it tightens. Once clamping begins, the ratchet will not release until it is fully clamped. So, once the tool releases from the ring, you can be confident that the PEX connection is perfectly tight and will not leak. It’s a brilliant, but simple, design.

IWISS PEX Cinch Clamp Crimping Tool for Stainless Steel Clamps from 3/8-inch to 1-inch with Calibration Gauge 20pcs 1/2-inch and 10 pcs 3/4-inch Clamps Suit ASTM F2098 Standards

• Plumbing Tools fits all pex cinch clamps except for Zurn Quick Clamp
• Used with Stainless Steel Clamps to make PEX connections

$29.68

Buy on Amazon Price & availability info updated 2026-05-15 at 13:49.

Cinch Clamp Rings

Of course, you’ll also need a supply of clamp rings. Again, we use ones with ears rather than the smooth type.

½” PEX Cinch Clamps are the most common for use in RVs:

Sale

LOKMAN 50 Pack 1/2 Inch PEX Cinch Clamps, Stainless Steel Rings Pinch Clamps for PEX Tubing Pipe Fitting Connections (1/2 Inch)

• HIGH QUALITY- 304 Premium Stainless steel material. Salt resistant, anti rust, anti-corrosion, construction.
• 360 °SEAL PROTECTION - These interlocking rings provide a fast and reliable connection of all PEX pipes fittings. Form a complete 360-Degree...

−$5.00 $13.99

Buy on Amazon Price & availability info updated 2026-05-15 at 12:47.

⅜” PEX Cinch Clamps could be required because some RVs use smaller PEX for branch lines to faucets and other uses:

Sale

LOKMAN 50 Pack 3/8 Inch PEX Cinch Clamps, Stainless Steel Cinch Crimp Rings Pinch Clamps for PEX Tubing Pipe Fitting Connections(3/8 In)

• HIGH QUALITY- 304 premium stainless steel material. Salt resistant, anti rust, anti-corrosion, construction.
• 360 ° SEAL PROTECTION - These interlocking rings provide a fast and reliable connection of all PEX pipes fittings. Form a complete 360-Degree...

−$0.61 $9.38

Buy on Amazon Price & availability info updated 2026-05-15 at 12:47.

Because many of us are visual learners, here’s a short video showing how to use a PEX crimp tool to secure PEX rings into place:

Digital Caliper: An Optional Tool for Working With PEX

Depending on what job you’re taking on, you may want to have a digital caliper on hand. Although it isn’t required for working with PEX, it’s useful for measuring the diameter of your existing PEX tube to determine the correct size. And there are so many other uses for a caliper that we love having one in our toolkit.

NEIKO 01407A Electronic Digital Caliper Measuring Tool, 0 - 6 Inches Stainless Steel Construction with Large LCD Screen Quick Change Button for Inch Fraction Millimeter Conversions, Digital Caliper Measuring Tool

• MULTI-FUNCTION: This measuring tool has a quick-change button that changes between three measuring modes such as inch, fraction, and millimeter to...
• THREE UNIT CONVERSION: The electronic digital caliper micrometer measurement range is 0” - 6” and 0 mm – 150 mm with a resolution of...

$28.31

Buy on Amazon Price & availability info updated 2026-05-15 at 12:33.

Can I Use PEX In My RV?

Absolutely! PEX is the plumbing choice that most RV manufacturers install in new RVs. PEX is lightweight, easy to work with, flexible and the best choice overall for most RV applications. Its light weight and flexibility make it perfect for our rolling homes.

What Size PEX is Used In RVs?

As we mentioned above, ½” is the most common size used in RVs. However, some RV manufacturers may also use ⅜” PEX for smaller lines to individual faucets, typically as a cost-and-weight-saving measure. This is why we recommend the digital caliper linked above: to measure your PEX tubing before attempting to repair or replace it. You’ll need the correct size rings for the PEX tubing you’ll be using.

You can also use this handy pipe size chart to measure the outer diameter of your pipes.

A Final Word About PEX

Working with PEX can unlock a range of DIY plumbing repair opportunities beyond simply fixing a leaking fitting. Once you’re comfortable with the tools and the general process, you can add new features or fixtures to your RV’s plumbing system. Want to install a shutoff valve to disable water flow to a particular part of your RV? No problemo! Want to plumb in a water heater bypass valve? It’s a CINCH! (Pun intended!)

Being big DIY RVers, we love being able to work on our own plumbing projects. And since we don’t have any experience soldering copper pipes, using PEX and the few tools needed lets us easily get the job done right.

In this video, you can see us doing our own leak diagnosis and repair, using our PEX tools:

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