Terms of the Trade: What Is a Water Hammer?
Have you ever been at home and heard a thumping or banging sound coming from pipes when a faucet or shower has been turned off? That sound is known as a water hammer. When the supply of running water is quickly shut off, an accumulation of pressure waves occur in the pipes, which causes the loud "hammering" sound. To prevent water hammers, you can install air chambers, which are vertical pipes next to the plumbing that prevent waves from occurring in the wall cavity.