Stop Banging Pipes (Water Hammer)
That bang when a washing machine or dishwasher shuts off is a shockwave from suddenly-stopped water. Left alone, it loosens joints and eventually causes leaks.
Tools
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Materials
- +Sioux Chief Mini-Rester — screws inline at the washing machine valves
Steps
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1
Try the air-chamber reset first
Many homes have built-in air chambers (capped pipe stubs above supply lines) that fill with water over time and stop working. Shut off the main water supply, open the highest faucet in the house, then the lowest. Let the system fully drain (5–10 min), then close everything and turn the main back on. Air chambers refill.
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2
If still banging — install arrestors
Most common at washing machines and dishwashers. Screw a mini water hammer arrestor inline between the supply valve and the appliance hose. Hand-tight plus 1/4 turn with a wrench.
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3
Check secure pipes
Hammering can also come from loose pipes vibrating in joists. Check accessible runs in the basement/crawlspace and add pipe straps or cushioned clamps where any pipe moves.