4 Causes of Noisy Pipes

February 07, 2022

Clanging, knocking or otherwise noisy pipes can keep you from enjoying tranquility at home. You’ll want to figure out and address the cause of the noise before it starts disrupting your life.

1. High Water Pressure

If you hear knocking sounds when your water is running or when you turn cold water taps off, water pressure may be causing the noise. When water under high pressure bounces around the inside of your pipes, they shake.

Use a water pressure test gauge on the hose bib close to your primary water main. If the reading is higher than 40 to 80 PSI, you may want a professional plumber to install a new pressure-reducing valve or adjust your current model to reduce the noise.

2. Water Hammer

You might have a water hammer issue if you notice a knocking sound when you shut off the water or turn off a tap. When moving water encounters a closed water valve, it abruptly stops and causes pipes to shake.

Water hammer is a serious issue. In some cases, the shaking may cause damage to the pipes and lead to leaks and water damage. If you live in an older home, you may have air chambers, which are empty pipes meant to absorb the shock of the water. If these air chambers fill with water, you’ll need to drain your plumbing then refill it to address the problem.

If you live in a home built in the 1970s or earlier, get a professional plumber to install or replace water hammer arrestors in your home to stop the noise and protect your pipes.

3. Poor Construction

Poor Construction

Poorly constructed pipes may not have enough room to naturally expand and contract, like hot water CPVC (chlorinated polyvinyl-chloride) pipes. If you notice knocking when turning on the hot water, your pipes may be the issue.

Often, poor construction requires complex repairs, such as cutting into walls, identifying affected pipes or even replacing them. If you suspect poor construction is the problem, a professional plumber can help.

4. Sediment Buildup

Over time, sediment can build up in your water heater tank. If steam bubbles disturb the sediment, it may cause a knocking sound. In addition to loud noises, you may notice your water temperature isn’t right or your tank’s efficiency drops.

Flushing your water heater tank can resolve the problem. Your water heater tank’s manual may have instructions to flush the tank, or you can hire a professional plumber for the job.

Soundproof Your Pipes

Fixing noisy water pipes begins with understanding the cause of the noise. However, even when you fix the issue, you may still hear water in the pipes, especially if they’re next to a bedroom or another quiet space. Soundproof Cow has a handy guide to help you soundproof your pipes and a range of high-quality products for your soundproofing project.