Bob Vila Radio: Water Hammer

If you hear a banging or thumping in the water lines, it's water hammer—and it's annoying. Here's an easy for any homeowner to remedy the issue.

Ever hear a banging noise when you shut off faucets in the house? The problem could be what plumbers call “water hammer.”

Water Hammer

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Listen to BOB VILA ON WATER HAMMER or read the text below:

That’s when a cushion of shock-absorbing air—which is supposed to reside in vertical air chambers of your plumbing system—becomes depleted. That causes water racing through the pipes to slam against fixtures when they’re shut off. There’s your noise.

Try this: First, close the main valve that supplies the house. Next, open the faucet that’s highest in the house. Do the same for the faucet that’s lowest. Be sure to flush all the toilets. As water drains from the pipes, in goes the air.

As soon as water stops draining from that lowest faucet, shut it off, then reopen the main valve. That forces air out of the system, except for where you want it: in those shock-absorbing air chambers.

Bob Vila Radio is a newly launched daily radio spot carried on more than 75 stations around the country (and growing). You can get your daily dose here, by listening to—or reading—Bob’s 60-second home improvement radio tip of the day.