PEX pipe is a soft, flexible pipe tubing made from cross-linked polyethylene. It is a relatively new product used for water-supply lines for household and business plumbing. One of the benefits of PEX pipe is that it does not require solder and heat to connect the fittings. Three types of fittings are compatible with PEX pipe: compression fittings, metal expansion fittings and plastic expansion fittings. Compression fittings are compatible with PEX as well as metal and plastic pipe for integrating PEX pipe to an existing plumbing system.

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Compression fittings have a gasket inside a ring that holds the pipe in place.

Step 1

Turn off the water to the house or to the section that you are connecting pipe to PEX pipe.

Step 2

Turn the knob on a pipe cutter to open it enough to fit around the existing pipe. Twist the pipe cutter around the pipe, tightening the cutting wheel with each revolution until the pipe is cut all the way through.

Step 3

Remove burrs and rough spots on the pipe by sanding the end of the pipe with 180-grit sandpaper.

Step 4

Press the new compression fitting onto the end of the pipe.

Step 5

Cut PEX pipe to the necessary length with a sharp utility knife or PEX cutters. Remove any rough edges with 180-grit sandpaper.

Step 6

Press the PEX pipe into the other end of the compression fitting.

Step 7

Complete the planned plumbing project and turn on the water supply.