Why Do Water Pipes Rattle and How To Fix Them?

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Water pipes rattling in your commercial or residential property and you’re losing sleep over this problem can be really frustrating. Knowing why it even happens and how to address it can save you from potential damage to the plumbing system and annoying noise.

Why Are My Pipes Suddenly Rattling?

Water Hammer

When the water is moving in the pipes and is somehow forced to stop or change direction all of a sudden, this is a water hammer. It causes a shock wave to travel through the pipes, and they bang against each other or the walls, which creates a loud rattle. The reasons are:

  • If a faucet or valve is closed quickly, it stops the water abruptly, causing a pressure surge.
  • Excessively high water pressure can worsen water hammers, which makes the noise louder and more frequent.
  • Longer pipes, if enough support is not there, are more susceptible to the quivering from water hammers.
  • Older systems without air chambers or water hammer arrestors are more prone to rattling pipes.

Loose Pipes

Over time, the straps and brackets holding pipes in place can wear out and loosen them due to regular use and vibration. This causes the rattling noises in any plumbing system. Pipes that were not also properly secured during installation can shift, move, and lead to rattling.

High Water Pressure

Normal water pressure in any home or building is somewhere between 40 to 80 psi. If it continuously exceeds the limit, it can cause pipes to shake more vigorously and create a rattling noise. In many cases, high water pressure often loosens the pipes too from their mounts, and result in loud clunking sounds coming out of them.

Thermal Expansion

Hot water flowing through pipes expands them. If they are installed in a way that they are tightly secured or pass through tight spaces, this expansion can create noise when they rub against their surroundings.

Air Bubbles

Air is often trapped in your plumbing system and can be the source of rattling pipes:

  • Sometimes, air can make its way into your plumbing system when you turn off the water and then back on during repairs.
  • If you’ve emptied the pipes for any reason, like draining, air can get trapped in them when they are refilled.
  • Some fixtures, like old faucets or valves, can draw in air and spurts when water is running.

How Do You Stop Pipes From Rattling?

Install Water Hammer Arrestors

You can buy and install water hammer arrestors at key points in your plumbing system, such as near washing machines, dishwashers, and other appliances that use quick-acting valves. It contains a piston or bladder that can absorb the shock wave when water flow is abruptly stopped and the pressure spikes by cushioning the impact.

Secure Loose Pipes

Pinpoint the location of the rattling by listening closely when the water is running. Look for pipes that are visibly loose or that move easily when touched. Pay attention to pipes in basements, crawl spaces, and under sinks.

After inspecting your plumbing system, use pipe straps, brackets, or clamps to tighten loose pipes. You can purchase them at a nearby hardware store, and they are easy to install. While doing it yourself, always make sure they are tight enough to hold the pipe firmly but not so much that they restrict water movement and cause damage.

Adjust Water Pressure

Check your property’s water pressure with a pressure gauge. If it exceeds 60 psi, consider installing a pressure regulator to bring it down to a safe level.

Insulate Pipes

Try using foam pipe insulation that can cover the pipes and stop them from rubbing against each other and the surrounding walls or obstacles. You can also place rubber paddings or gaskets around pipes where they pass through walls or floors. This can help absorb vibrations and, eventually, prevent them from rattling.

Bleed Pipes

The most effective way to remove air bubbles is to bleed the pipes:

  1. Turn off the water from the main valve.
  2. Starting from the highest point in your property, open all faucets (sinks, showers, and outdoor spigots).
  3. Flush all toilets to help drain the water from the system.
  4. Let the water run out until no more of it comes out of the faucets.
  5. After draining the plumbing system, close all faucets and let the toilets refill.
  6. Slowly turn the main water supply back on to stop a sudden rush of water that can introduce new air bubbles.
  7. Open the lowest faucet and work your way up to the highest one to allow air to escape.

Air chambers (vertical pipes installed near faucets and appliances) can also become waterlogged and no longer absorb shock to prevent air bubbles from causing a rattling noise. To fix them:

  1. Shut off the water supply to your commercial or residential building.
  2. Follow the same steps mentioned above for bleeding the plumbing system.
  3. Turn the main water supply back on slowly to let the air chambers refill with air.

TIP: Remove and clean aerators on faucets and check the valves or connections for leaks that might be letting air in.

Ask a Professional for Thorough Inspection

If you can’t identify where the rattling is coming from or fail to fix it, call a professional plumber. They can check your plumbing system and tell you which pipes are stressing and causing this problem. They can also diagnose hidden causes that indirectly result in pipes shaking and making a clunking noise. 


By addressing these common causes, you can eliminate the rattling noise from your pipes and ensure a smoother, quieter plumbing system on your property.