Noisy Pipes and Water Hammer: What's That Banging?

If your pipes bang loudly when you shut off a faucet or when an appliance cycles, you're likely hearing water hammer. Beyond the noise, it can stress your plumbing over time. Here's what's happening.

What is water hammer?

Water hammer is the shock wave created when fast-moving water suddenly stops, slamming against valves and pipe walls. The result is that distinctive banging sound.

Other causes of noisy pipes

• Loose pipe straps allowing movement
• High water pressure
• Worn-out air chambers
• Pipes rubbing against framing

How it's fixed

Solutions range from installing water hammer arrestors and securing loose pipes to adjusting water pressure. A professional can identify which applies to your home.