How to Cap Water Pipes With Push-to-Connect Fittings

Copper water pipe capped on end with push-to-connect fitting

The Spruce / Kevin Norris

Project Overview
  • Working Time: 15 mins
  • Total Time: 15 mins
  • Yield: 1 capped pipe
  • Skill Level: Beginner
  • Estimated Cost: $7 to $8 per pipe cap

Temporarily capping water-supply pipes is often necessary during a kitchen or bathroom renovation. For example, when replacing cabinets, you may find that the water supply pipes extend through the back or bottom floor of a sink cabinet. Rather than cutting out a large section of the cabinet to remove it, it's usually far easier to cut off the ends of the pipes and cap them with easy-to-use push-to-connect fittings, which will work with copper, CPVC, or PEX plumbing pipes. The only drawback to this type of fitting is that they are relatively expensive when compared to other capping methods, but for most people, the ease of use is worth the price.

Warning

If not installed properly, excess pressure or water hammer occurs and these fittings can blow off, causing extensive flood damage if no one is home. As a fitting for a permanent capped line in a wall, soldered fittings are a safer option for the DIYer.

Before You Begin

"Push-to-connect" is a generic name for a type of pipe fitting now made by several different manufacturers—one of the most popular is SharkBite, a name that has become synonymous with this type of fitting. These fittings are sometimes sold as "push-to-fit" connectors.

Rather than using mechanical or soldered connections, push-to-connect fittings work via a system of internal seals and sharp barbs that grip the pipe securely. Push-to-connect fittings are now allowed by nearly all plumbing codes across the country.

In addition to the simple caps described here, there are many other push-to-connect fittings available, including couplings, elbows, and adapters. These fittings have largely eliminated the need for torch soldering and other more complicated methods of fitting pipes.

What You'll Need

Equipment / Tools

  • Tubing cutter or hacksaw
  • Metal file (if needed)
  • Rag
  • Tape measure
  • Marker

Materials

  • Emery cloth (if needed)
  • Push-to-connect pipe caps

Instructions

Materials and tools to cap a water pipe

The Spruce / Kevin Norris

  1. Shut Off the Water

    Shut off the water supply to the house. Since you'll be cutting the water pipes behind or below the shutoff valve on each pipe, you must shut off the water at the main shutoff valve.

    Drain residual water and pressure from the pipes by turning on an outside spigot or a faucet that is lower than the pipes you are working on (such as on a basement washtub). This minimizes the amount of water that spills out of the pipes when you cut into them.

    Water supply turned off by turning shutoff valve

    The Spruce / Kevin Norris

  2. Cut Off the Pipes

    Cut off the water pipes, using a tubing cutter if you have enough room to rotate the tool around the pipe. You can also use a hacksaw, but be careful to make a clean, square cut to ensure a proper seal with the push-to-connect caps. Leave as much pipe as possible so you won't have to add an extension later when reconnecting the fixture.

    Copper water pipe being cut with hacksaw

    The Spruce / Kevin Norris

  3. Clean the Pipe Ends

    Clean the end of each cut pipe with a rag. It must be smooth and free of old solder or other material. If you cut the pipes with a hacksaw, file off any rough edges before cleaning. If necessary, you can smooth rough surfaces with emery cloth, but be careful not to sand down the pipe; it should have its original roundness and diameter to ensure a proper seal with the push-to-connect fitting.

    Cut end of copper pipe smoothed with emery cloth

    The Spruce / Kevin Norris

  4. Cap the Pipes

    Measure from the end of each pipe and make a depth marking, as directed by the push-to-connect fitting manufacturer. The mark will tell you when the fitting is pushed on all the way, which is essential for a proper seal.

    Push the pipe cap onto the pipe until its edge reaches the depth mark.

    Tip

    Push-to-connect hardware works for copper, CPVC, and PEX water pipe. Most include a stiffener—a small plastic cylinder—that slips into the end of the pipe to provide rigidity when you are capping PEX tubing. The stiffener is not required with copper or CPVC pipe.

    Push-to-connect fitting capping end of cut pipe

    The Spruce / Kevin Norris

  5. Test the Capped Fittings

    Turn the water back on and check the cap connections for leaks.

    Push-to-connect fittings can be temporary or permanent. Most include a release feature that allows you to remove the fitting with a special tool, which is usually a simple plastic device that you push against the fitting to depress a release collar and slip off the fitting. Always use the manufacturer's tool to remove the fittings.

    Push-to-connect fitting tightened on end of copper pipe

    The Spruce / Kevin Norris