Aside from the rush of the water, your pipes should be pretty quiet. However, if you hear a rattle in your pipes, especially right after you shut off a valve, it may be a so-called “water hammer”. This occurs when the flow of water stops abruptly or changes direction, creating a shock wave that can cause popping noises and rattle loose pipes. Possible causes are high water pressure or, in older houses, flooded air chambers in your plumbing system. Rattling noises can also be caused by poorly secured pipes.
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