How to Fix Plumbing Noises In Your Home

To diagnose loud plumbing, you must first determine whether the unwanted sounds occur on the system's inlet side - in other words, when water is turned on - or on the drain side. Noises on the inlet side have various causes: excessive water pressure, worn valve and faucet parts, poorly connected pumps or other appliances, incorrectly placed pipe fasteners, and plumbing runs with excessive tight bends or other restrictions. Noises on the drain side usually originate from poor location or, as with some inlet side noise, a layout with tight bends.

Hissing

Hissing that occurs when a faucet is opened slightly generally signals excessive water pressure. Consult your local water company if you suspect this problem. They will tell you about the water pressure in your area and if necessary, can install a pressure reducing valve on the incoming water supply pipe.

Thudding

Thudding, often accompanied by shuddering pipes when a faucet or appliance valve is turned off, is a condition called water hammer. The noise and vibration are caused by the reverberating wave of pressure in the water, which suddenly has no place to go. Sometimes opening a valve that discharges water quickly into a section of piping with a restriction, elbow, or tee fitting can produce the same condition. Water hammer can usually be fixed by installing fittings called air chambers or shock absorbers in the plumbing to which the problem valves or faucets are connected. These devices permit the shock wave produced by the halted flow of water to dissipate in the air, which unlike water, is compressible. Older plumbing systems may have short vertical sections of capped pipe behind walls on faucet runs for the same purpose; these can eventually fill with water, reducing or destroying their effectiveness. The solution is to drain the water system by turning off the main water supply valve and opening all faucets. Then open the main supply valve and close the faucets one at a time, starting with the faucet closest to the valve and ending with the one furthest away.

Chattering or Screeching

Intense chattering or screeching that occurs when a valve or faucet is turned on, and that usually disappears when the fitting is fully open, signals loose or defective internal parts. The solution is to replace the valve or faucet with a new one. Pumps and appliances such as washing machines and dishwashers can transfer motor noise to pipes if they are improperly connected. Link these items to plumbing with plastic or rubber hoses - never rigid pipe - to separate them.

Other Inlet Side Noises

Creaking, squeaking, scratching, snapping, and tapping are usually caused by the expansion or contraction of pipes, generally copper ones supplying hot water. The sounds occur as the pipes slide against loose fasteners or strike nearby house framing. You can often pinpoint the location of the problem if the pipes are exposed; just follow the sound when the pipes are making noise. Most likely, you will discover a loose pipe hanger or an area where pipes lie so close to floor joists or other framing pieces that they clatter against them. Attaching foam pipe insulation around the pipes at the point of contact should resolve the problem. Be sure straps and hangers are secure and provide sufficient support. Where possible, pipe fasteners should be connected to large structural elements such as foundation walls instead of framing; doing this reduces the transmission of vibrations from plumbing to surfaces that can amplify and transfer them. If attaching fasteners to framing is unavoidable, wrap pipes with insulation or other resilient material where they contact fasteners, and sandwich the ends of new fasteners between rubber washers when installing them. Correcting plumbing runs that suffer from flow-restricting tight or numerous bends is a last resort that should be performed only after consulting a skilled plumbing contractor. Unfortunately, this situation is common in older homes that may not have been built with indoor plumbing or that have been through several remodels, particularly by unprofessional contractors.

Drainpipe Noise

On the drain side of plumbing, the main goals are to eradicate surfaces that can be struck by falling or rushing water and to insulate pipes to contain unavoidable sounds. In new construction, bathtubs, shower stalls, toilets, and wall-mounted sinks and basins should be set on or against resilient under-layments to lower the transmission of sound through them. Water-saving toilets and faucets are less noisy than conventional models; install them instead of older types even if codes in your area still allow older fixtures. Drainpipes that do not run vertically to the basement or that branch into horizontal pipe runs supported at floor joists or other framing present especially troubling noise problems. These pipes are large enough to radiate substantial vibration; they also carry significant amounts of water, which makes the situation worse. In new construction, use cast-iron soil pipes (the large pipes that drain toilets) if you can afford them. Their immense size contains much of the noise made by water traversing them. Also, avoid routing drainpipes in walls shared with bedrooms and rooms where people gather. Walls containing drainpipes should be soundproofed as stated earlier, using double panels of sound-insulating fiberboard and wallboard. Pipes can be wrapped with special fiberglass insulation made for the purpose; these pipes have an impervious vinyl skin that sometimes containing lead. Results are not always acceptable.