Pipes that rattle and hammer are not only annoying, but they also may eventually come apart at the joints. Take steps to stop the noise and prevent possible leaks.
The most common noise is water hammer, a rattle that occurs when water is turned on or off by a faucet or an appliance, such as a dishwasher or washing machine. The solution is to install a shock absorber, also called an air chamber, which provides a cushion to dampen the water's movement.
The following instructions show how to install a shock absorber using threaded fittings. You can also fabricate one for plastic pipe using a piece of pipe and a cap fitting.
After a few years the air chamber may fill with water and lose its ability to soften water hammer. Draining and refilling the line will replenish the chamber with a cushion of air.
An hour or so to install a pipe shock absorber
Groove-joint pliers, tubing cutter, hacksaw, multiuse wire brush, flux brush, propane torch, fiber shield; or tools for working with plastic or steel pipe
Skills Cutting and joining copper, plastic, or steel pipe
Shut off the water and drain the line
Shock absorber for your type and size pipe, materials for joining the pipe, possibly insulation
On each side of the absorber location, slip a compression nut on the pipe, threaded side toward the absorber, then slip on a ferrule. On each side of the shock absorber, push the nut over the ferrule and finger-tighten the joint. Use an adjustable wrench to complete the installation.