Why does my water pipes making noise humming?

by jessica | Last Updated: May 20, 2020

Your house speaks to you. And no, this is not a metaphor: your house, when it has a problem, really talks to you. Have you heard that lingering noise in the pipes that greets you when you turn on or off a tap, or when you’re so calm watching TV on your couch? Well, it is a nuisance that 45% of Spaniards suffer.

Why do water pipes make noise?

Although, in principle, a noise in the pipes is not as alarming as these eight sounds that your house should never make , it should be a wake-up call. Do not resign yourself to living with this invisible sound company. Discover the causes of pipes hum after flushing toilet and how to shut them up once and for all. You just have to interpret these signals that we decode today with you on HomeServe.

1.  Noise of pipes when closing the faucet

If when you turn off any of the taps in your house you hear a clatter inside the pipes, or a sound similar to that of marbles falling, it is most likely due to the phenomenon known as water hammer. The sudden interruption of the water flow in installations where there is an excess pressure, or in which the pipes are very narrow, causes liquid particles to crash violently against the walls of the pipes and this characteristic noise is generated in the pipelines.

Solutions to control water hammer

-Close the taps more slowly, or replace them with others with progressive closure.

-Regulate the water pressure at the outlet of the taps.

-Adjust the water pressure at the inlet of the installation. Reinforce the support of the pipes that pass through the false ceilings.

2. Whistle as the water runs down the pipes

The noise of the pipes when air collects inside them is reminiscent of a hissing sound, and is very common when the pipes have been out of use for weeks or months.

Solutions to extract air from pipes

Usually it is enough to let the water run for a few seconds but, if this is not enough, try turning off the faucet of the whole house, turning on the taps and allowing the water accumulated in the pipes to drain. Then cut them again, and reopen them once you’ve restored the supply. Wait until you hear the water flow smoothly through the inside of the pipes.

3. Pipe noise in the form of rattle

When the plumbing installation is very old, the most typical noise of pipes is the rattle , attributable to the fact that the pipes tremble when the water passes through them.

Solutions to avoid the rattle of pipes

-Check the clamps and anchors that ensure the stability of the pipes, and tighten them if they are loose.
-Place small padded pieces or rubber between the pipes and the clamps and walls in contact with them so that the friction between elements does not cause noise.

4.  Noise of pipes when opening the hot water faucet

The squeaking of the pipes when opening the hot water faucet has a very clear culprit: the expansion in contact with a liquid at high temperature, which causes the pipes to start rubbing with anchors and clamps.

Solutions to keep pipes from squeaking

The same as when the pipes rattle: check the condition of the clamps, adjust or replace them, and place a damping object if necessary.

How to stop pipes humming?

In the case of water hammer, plumbers install devices they call “anti rams”. These are sealed jars fitted with a membrane which separates the water from the circuit from a part filled with air. And which therefore attenuates the shock wave. It is also recommended to review the plumbing fixings to limit vibrations. Plastic fasteners are more effective in this specific case. You can also reduce the water hammer effect by reducing the water inlet pressure.

The expansion and contraction noises of hot water pipes can be attenuated simply by wrapping them with adhesive tape or a plastic sheath where the blows take place.

Regarding flushing and other noisy drains, the solution is to insulate the pipes . If it is possible to include them in walls far from living areas, it’s even better!

Fog horn noise when flushing toilet

The popping noises that you notice in the heating pipes can come from the expansion due to a significant temperature variation. In this case, fixing the heating network pipes is probably the cause of the problem. Thus, if the fixings of the pipes are not suitable, the clicking noises can intensify further. You will therefore need to check all the pipes in the network, to make sure that each fixing is suitable, and loosen the clamp screws that allow the pipes to be fixed to the wall, if necessary.

In addition, you can buy collars with noise dampers for less than 5 euros , which have a rubber protection preventing metal elements from colliding and generating these clicking noises.