Friday Fact: That Bang in Your Pipes Has a Name

Hear a bang, thump, or rattle when you shut off a faucet? That’s called water hammer — and it’s not a ghost, even in October.

Here’s what’s happening: water moving through your pipes has momentum. Slam a valve shut and all that moving water has nowhere to go, so it fires a pressure spike back through the system. That spike is the bang.

An occasional knock is mostly harmless noise. But chronic water hammer deserves attention — those repeated surges loosen pipe joints over time and beat up valves and appliance solenoids. Your washing machine and dishwasher feel every single one.

The usual culprit is pressure running too high. Anything above 80 psi is asking for trouble, and plenty of homes sit well above that without knowing it. A ten-dollar gauge that screws onto a hose bib tells you your number in thirty seconds.

The fix for stubborn hammer is a water hammer arrestor — a small device that absorbs the shock, installed near the offending valve. Cheap, simple, and any plumber knocks it out fast.

So if your walls go bump this month, now you know its name — and what to check first.

Inspired by the Water Quality Association‘s Fun Fact Friday