Easy Fixes for Noisy Pipes

Water rushing through the pipes in your home will always make some noise, but loud bangs, knocks, shrieks and whistles are usually a symptom of a problem that may have a simple solution.

Pack your pipes

Bangs and creaks under the floorboards are usually caused by the expansion and contraction of hot water and central heating pipes. The noise means that the pipes are rubbing on joists or floorboards and have no packing around them to allow them to slide quietly.

Stopping the noise isn't hard, but tracking down its source requires floorboards to be lifted — not an easy job and one for which you may need professional help.

Pipes usually run across joists in notches under the floorboards. They should ideally be clipped down on every joist with a special plastic joist clip that holds the pipe securely but allows for silent expansion and contraction. If the pipe isn't clipped, wrap it with felt, strips of old towel or foam pipe insulation where it crosses the joists — this will allow the pipe to expand quietly.

Clip your pipes to keep them from knocking

A banging sound that reverberates through the pipes when a faucet is turned off or a washing machine stops filling is caused by water hammer. Sharp knocking noises also result from unsupported pipes that move when under pressure, banging against adjacent walls or floors.

• Partly close the service valves on water pipes supplying the sink or appliance near the source of the sound. This will ease the pressure of water when the tap or valve is closed, reducing the noisy shock waves at the cost of increasing the appliance's fill time a little.
• An unsupported pipe will move as water flows within. Make sure all the pipes in your home are clipped securely to the wall or floor at least every six feet or so. Plastic pipe clips are inexpensive and available from all home improvement stores.

If you need to enlarge a notch in a joist to accommodate a pipe, take care not to make the notch too deep or you will weaken the structure. The golden rule is to cut no deeper than one-eighth of the way into the joint.

Replace a faulty washer

A washer loses flexibility as it ages, and water rushing past makes it flutter like a reed in a clarinet, creating a tuneful noise. To silence a singing tap, simply replace the washer.

Get rid of system airlocks

If your hot-water tap splutters and delivers water as a series of gushes rather than an even flow, you probably have an airlock in your system.

• Open all the taps in the house to see if the additional flow moves the air bubble.
• If you have separate taps in the kitchen, attach a length of hose between the cold and hot taps and secure it tightly into position using hose clamps. Fully open both taps — the pressure from the cold will push water back up the hot pipe into the overflow tank, hopefully shifting the airlock in the process.
• Alternatively, if you have a mixer tap in the kitchen, put on a rubber glove and hold your hand tightly over the spout. Open the hot and cold levers.