Plumbing issues can cause loud vibrations in the walls of your home. The most common, a repeated banging noise called water hammer, has a particular cause and a simple solution. If you experience this problem it, there are a number of solutions available to you.
What Is Water Hammer?
Water hammer is the sudden banging or pulsing of pipes in the walls of your home when the water is turned on or off. It is a short rattle and quite loud, depending on how hard the pipes shake and bang against the walls. The intensity of the noise sometimes increases in homes with more water pressure. If you hear a thundering rattle from your pipes when you turn a faucet or showerhead on or off, chances are the noise is water hammer.
The Causes of Water Hammer
There is only one cause of water hammer: water pressure changes inside the pipes. This is why it only occurs when the water turns on or off. Water runs through pipes like a train through a subway tunnel. If it stops suddenly, the cars pile up and bang into one other, causing a vibration to run through the subway. The water is simply backing up inside your pipes and shaking them to release this built-up energy.
The most common solution for water hammer is to reduce the pent-up energy in the pipes. This is accomplished in many ways. One is to install an air gap or air chamber in the pipe near the faucet. This is an empty chamber that allows the pressure to diffuse without backing up into the pipes. It is like an air cushion for the subway cars, metaphorically. Another solution is installing a surge tank, which is similar to an air chamber. Reducing water pressure by reducing the horsepower of your pump is yet another option.
To prevent water hammer in a home or building, the pipes must be able to handle the incoming water pressure, or operating water pressure, of the home and the surge pressure. The surge pressure is the amount of pressure caused by a sudden change or surge in water through the system. This is accomplished using complex mathematical formulas to measure the incoming water pressure levels and pipe strength. A plumber and building designer incorporate these into their plans before building the home. If you install your own water pump or plumbing, you need to heed these pressure levels.