If you’ve determined that your home is ready for a new set of pipes, then you’ve probably already heard of the beauty of PEX piping. This piping material is easier to work with and extremely durable and strong. If you’re trying to replace the copper pipe with PEX, read about the process in our step-by-step guide below.

1. Turn Off the Water Supply

Locate the main water supply in your home and turn it off completely. This will reduce the pressure in the pipes, making it safe for you to work with them.

2. Drain the Pipes

Once the water supply is off, you will need to drain the pipes of the remaining water. Do this by turning on the faucet in the lowest part of the home, like in the basement or first-floor bathroom.

3. Cut the Ends of the Copper

Determine the section of copper you are replacing and mark it for cutting. Take your copper tubing cutter and cut off both ends of the copper.

4. Cut the Fixture Supply Branches

If you are working with a section of piping that includes branch lines, you will need to cut these as well with your tube cutter. You might need to use a wrench to remove these lines if they were secured with metal couplings.

5. Smooth the Burred Ends of the Copper Pipe

Now you will need to smooth out the burred ends with a copper de-burring tool. Also, use the tool to remove any remaining corrosion inside and outside the pipe.

6. Cut a Section of PEX Tubing

To replace the copper pipe removed, measure and cut PEX tubing long enough to replace the removed section.

7. Connect the PEX to the Copper

Just like you did with the copper tubing, clean the end of the PEX tubing and remove any burrs on the ends. Attach one end of a push-fit straight connector to one of the cut ends of the copper pipe. Connect the pipe to the connector and ensure the connector reaches the marking you made on the pipe. Push the PEX tubing to the depth line in the other opening of the straight connector.

8. Connect Fixture Supply Lines to the PEX

Cut into the PEX line and attach a tee fitting. Attach the PEX line to two outlets and the supply line to the fixture to the third.


  • Whenever replacing corroded pipes, ensure that a larger section of copper is cut beyond the corroded area to ensure that the corrosion has been eliminated.
  • When cutting copper in tight corners, you may want to opt for a mini tubing cutter for better reach.


  • Do not attempt to replace the pipes while the water supply is still on and the pipes have not been drained.

Tools Needed

  • Marker
  • Copper tubing cutter
  • Drill-driver
  • Copper pipe deburring tool
  • Tape measure
  • PEX tubing cutter
  • PEX tubing
  • Push-fit straight couplings
  • Push-fit tees
  • Copper pipe straps and screws

Related Content: Florida Plumbers Explain How Water Pipe Replacement Is Done

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