The sound of rattling pipes can be startling and a little unnerving—after all, when you turn on the faucet to your sink or bathtub, you don’t expect to hear anything except for the sound of water rushing out of it. But suddenly, you also get loud clanks and bangs of your pipes shaking around.
“What’s going on?” you might think. “Is that normal? Should my pipes be rattling like that, or can I just ignore this?”
No, it’s not normal. And even though some people will dismiss clanking, rattling plumbing as something that just happens as a home ages, you shouldn’t let yourself ignore this problem so casually. Rattling pipes are a sign that something is wrong.
However, you shouldn’t panic either. There are several likely explanations behind these rattling pipes. It might be that the pipes aren’t secured in place, and the change in pressure when you turn on the water supply causes them to move around, ultimately hitting other pipes or the home infrastructure surrounding them. Unsecured or loose pipes could have been installed by a plumber who was doing a poor job, or they could loosen over time (this is why rattling pipes are common in old houses).
Let’s take a look at some of the specific causes of loose pipes and what can be done to address them. This problem can sometimes be attributed to a water hammer or loose mounts. There’s also the possibility that it’s caused by high water pressure.
What’s a Water Hammer?
A water hammer is a phenomenon that happens when air builds up in your pipes. In a properly functioning plumbing system, water will go through a pipe and create a vacuum. The excess air will then be vented out into air chambers, which are installed vertically in a location close to your faucet. But if this vent gets clogged or blocked, the pressure can build inside the pipes, causing them to move ever so slightly.
If you need to correct this problem, take the following steps:
Find your home’s main water supply and turn it off.
Go to the faucet in your home at the highest location (such as an upstairs bathroom, ideally one that’s far away from the main water supply). Turn the faucet on.
Now go to the faucet that’s at the lower point in your home (such as a basement bathroom or sink, ideally one that’s closest to the main water supply). Turn this faucet on too.
Allow both faucets to run for several minutes. After a little bit of time, all the water will have flowed sufficiently through your water supply line and throughout your whole home. This will have forced any air in the pipes out of them.
Start by turning off the lowest faucet, followed by the highest faucet. This should resolve any rattling problems if they are due to a water hammer.
What Are Loose Mounts?
Loose mounts are exactly what they sound like: The mounts that hold your pipes in place have come loose or are fitting poorly around your pipes. You can usually diagnose a loose mount by taking a close look at all of the pipes throughout your home. Pay close attention to places where the pipes pass through the mounts, especially in corners or where the pipes cross in T-joints.
If the pipe is loose within the mount, you can expect it to move around and bang into the mount itself, another pipe, or a nearby wall. Tighten these mounts and the problem should go away. You should also check these loose mounts to make sure there are no leaks around them. Leaks and loose mounts are usually found together.
What About High Pressure?
The final problem that your rattling pipes could be attributed to is high water pressure. You usually notice a problem like low water pressure because you go to take a shower or wash the dishes only to discover the flow of water coming out of the faucet is weak (sometimes too weak to sufficiently shower under it).
High water pressure isn’t so easy to notice because most people appreciate a strong, heavy flow of water coming out of the faucet. However, if the water is going through your pipes so forcefully that it is causing them to move around, then your water pressure is too high. A sign of rattling pipes due to high water pressure is if the rattling sound happens as soon as you turn your faucet on, instead of after the water is running for several seconds or several minutes.
The best way to solve the problem of high water pressure is by installing a reduction valve or a pressure regulator, which will slow the speed at which the water enters your home’s plumbing system. Reduced water pressure will also put less of a burden on any appliances attached to your water supply.