There are a few different reasons why pipes rattle: a loose mounting strap, water hammer, or even water pressure that is too high can all result in pipes that rattle and make a lot of noise. You shouldn’t ignore these noises because they indicate that there is something wrong with your pipes, if the sound and vibrations worsen it can cause pipes to break and leak creating an even bigger problem than some loud noises. To find out the top causes for rattling pipes and how to remedy the problem, read the rest of the article below.
Water hammer is often the problem and rattling pipes/vibration are the symptoms. Water hammer is the term for water that has had to come to a complete and sudden stop due to a valve that has closed suddenly. Water hammer looks like this video. When the water has nowhere to go the sudden stop causes it to create a very loud thudding and reverberation inside the pipe and even cause a vibration that can be felt through the walls!
So how do you fix water hammer? You need to create a pocket of air to cushion the water when the valves are shut off. Most faucets include an air chamber that keeps the pipes from water hammering, sometimes in a broken or leaking faucet the air runs out of these air chambers and the result can be a water hammer. To fix this issue you need to refill the air chambers.
To do that you need to completely drain the water from your home, as the water is drained from the pipes it will immediately be refilled with air creating the air cushions that are necessary to prevent water hammering. As soon as the last bit of water comes out of your home turn on the water again, filling the pipes with water after the air cushions have been replenished. Then test the faucets to be sure there is no more hammering.
Another option is a water hammer arrestor. To see how to install one check out this clip where the pros at This Old House do the arrestor installation.
Sometimes a broken mounting strap can cause rattling and water hammering within the pipe. A plumbing mounting strap is made out of metal plumbers tape or vinyl hooks and hangers that attach the pipes to the framing of a house inside the walls. If this mounting strap breaks due to age or wear and tear it will allow the pipe to vibrate and bang freely against the wall. This does require a full-on water pipe repair, just some steadying of the pipe. To stop rattling and water hammer you should check that all your pipes are secured tightly with plumbers mounting straps and reattach when necessary.
Water pressure that is too high forces water through the pipes faster than needed resulting in water hammering when the air chamber gets flooded because of how fast and forcefully the water is travelling to the faucet. To fix this issue adjust your water pressure regulator, which is usually found where your main water supply enters the home. Be sure to keep your water pressure between 30 and 55 PSI to ensure it is not too high to cause damage that could result in water hammering and noise.
Now that you know how to prevent water hammering and rattling in your pipes be sure to follow the advice in this article and take preventative measures to ensure that your pipes stay quiet and you keep your sanity!