Copper Pipe to PEX Pipe: Faster and Easier Than You May Imagine

  • 01 of 07

    Easy Fix Replaces Leaky Copper Pipe With PEX

    Replace Copper Pipe With PEX Pipe
    Replace Copper Pipe With PEX Pipe. Lee Wallender

    As you remodel, walls and ceilings open up. Instead of spot-fixing corroded copper pipe, replace as much as is visible with PEX pipe--entire runs, including tie-ins to toilet, sink, shower, etc. What makes this job a snap is that you will be using simple-to-understand plastic PEX pipe and SharkBite connectors. PEX can be effectively and safely mated with copper pipe, no soldering required.

    Your DIY Plumbing Options

    When you have corroded or leaking copper pipes, you have a few options. Starting...MORE with the most ambitious and costly and working down to the easiest option:

    1. Re-Pipe: Cost aside, functionally the best solution is to re-pipe your home. Bypass all of your existing copper and run new pipe with PEX. You can either follow the current pattern or start anew with a manifold-and-branch system.  
    2. Spot Fix: When you find leaking copper pipe, cut out the bad section and replace the bare minimum. Often, you can get by with installing just a single SharkBite fitting in that area. If you want the option of turning off water mid-line, buy a slip ball valve. If you just want the simplest SharkBite fix, install a slip coupling.  Buy on Amazon - SharkBite Slip Ball Valve
    3. Replace Visible Runs: This guide is about this option, a compromise between full re-piping and small patches. Basically, you are taking the "spot fix" option a step farther by using entire 10 feet or greater lengths of PEX pipe and branching out where needed. While this may sound complicated, it is not much harder than the "spot fix" option.

    Tools, Materials, and Parts

    • Two (2) 10' sections of PEX pipe
    • Two (2) Brass-to-connect 1/2" tees
    • Two (2) Brass-to-connect 1/2" straight coupling
    • One (1) SharkBite PEX pipe cutter
    • One (1) HDX Junior Pipe Cutter (for copper)
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  • 02 of 07

    Identifying Pinhole Leaks in Corroded Copper Pipe

    Pinhole Leaks In Copper Pipe
    Pinhole Leaks In Copper Pipe. Lee Wallender

    One of the least appealing aspects of home remodeling is dealing with old, corroding copper pipe when you would rather be doing something else with your house.  

    When pipe corrodes, leaks often do not gush forth and make themselves obvious. Here are three ways you might know you have bad copper long after the copper has turned on you:

    1. You Smell It: Over time, you begin to notice a stale, musty smell that you cannot quite identify. It is even more confusing if the smell is in a laundry room,...MORE bathroom, or child's room, because you naturally think that the smell is related to the room.  But the odor is more like stagnant pond water, and it persists.
    2. You See Evidence: Wide bulges develop on the ceiling or on walls. This is due to pinhole leaks in the copper slowly dripping on the drywall, causing it to expand.
    3. You See It: You open a wall or ceiling to do something else, like adding insulation, and you notice that the copper pipe is green, crusty, and corroded. It may even have pinhole leaks that are acceptable. These leaks are so slow that they dry on the pipe even before falling. Or if they do fall, the drywall or stud dries at a faster rate than the leaking pipe can cause any real problems.

    All of this means that your copper pipe is on its way out.  

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  • 03 of 07

    Cut Out Both Ends of Copper Pipe

    Cut Both Ends of the Copper Pipe
    Cut Both Ends of the Copper Pipe. Lee Wallender
    • Start with the bad, corroded, and possibly leaking section of your copper pipe.
    • With a tube cutter, cut to the side of this bad section, at least a few inches past so that you are well past the corroded area.
    • Temporarily support this area. One way is to loop a wire around this dangling section and drive a screw into a stud.  The loop hangs over the screw.
    • Use your tube cutter to cut the other end of your copper pipe. Length is dependent on how much copper pipe is accessible.  
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  • 04 of 07

    Cut Out Lines That Tie to Toilets, Sinks, or Showers/Baths

    Cut Off Toilet and Sink Lines
    Cut Off Toilet and Sink Lines. Lee Wallender

    If the section you are removing includes lines that tie into to services, such as toilets, sinks, showers, bathtubs, or any other water supply-related service, you will need to sever each of these connections.

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  • 05 of 07

    De-Burr All Ends of Copper Pipe

    De-Burr Copper Pipe
    De-Burr Copper Pipe. Lee Wallender

    With your copper de-burring tool, run the tool thoroughly on the inside and outside of all cut copper pipe. Run it a couple of inches up the pipe to make sure that all corrosion is removed.

    Continue to 6 of 7 below.
  • 06 of 07

    Connect New PEX Pipe to Old Copper Pipe

    Connect Each End of Copper With PEX
    Connect Each End of Copper With PEX. Lee Wallender

    Connect both severed ends of copper pipe to PEX pipe. If you have branch-outs, do not worry about this right now; you will address this shortly.

    You can connect copper to PEX in a number of ways. The easiest way is with a SharkBite straight connector. If you anticipate having access to this area after the repair, you may decide to install a valve. The valve will remain open all the time. If there is an emergency, you can shut off water with this valve.

    It is recommended that you leave some slack...MORE in PEX pipe account for contraction and expansion. 

    Continue to 7 of 7 below.
  • 07 of 07

    Install Lines to Tie to Toilet, Sink, Shower

    Replace Branch-Outs To Toilet, Sink, Shower/Bath
    Replace Branch-Outs To Toilet, Sink, Shower/Bath. Lee Wallender

    Now you can cut into your newly installed PEX line at any point where you need to tie into a sink, toilet, shower, bathtub, etc.

    Use a SharkBite 1/2" tee to connect the two severed portions. With the open part of the tee, you can tie directly into the copper stub-out.