Has this happened to you? You’re enjoying a peaceful evening at home when you turn on the faucet or flush the toilet, when suddenly, you hear mysterious banging sounds coming from the ceiling or walls. You listen carefully, and the sounds gradually disappear. This is a good thing, but if you’re frequently hearing a knocking noise, something needs to be done. 

There is usually a simple explanation for why your walls are making a knocking sound. Most often, it’s your home’s plumbing system. It may be due to fluctuating water pressure issues, loose plumbing pipes, or a faulty valve. 

To help find the problem and solve it, the first thing you need to do is take note when you hear the banging noises. You should also include information about any running appliances like the dishwasher, refrigerator, and/or sprinklers. When you begin to narrow down the location of the pipes involved, addressing the issue will be easier.

What Causes Knocking Pipes?

There could be several different “triggers” for these noises. Sounds are often heard after a water supply is turned on or shut off, and a banging noise may occur randomly, day or night. 

The type of piping you have will also affect the noise level of the knocking or banging sound (copper piping is generally noisier than plastic piping).

Furthermore, banging is also more common in hot water pipes than cold water ones because they expand and contract the most.

To help you identify the problem, here are the top causes of banging plumbing pipe sounds.

High Water Pressure 

The water pressure may just be too high. When this happens, your pipes can start to bang in protest. 

It’s recommended that water be delivered to your home at no lower than 40 psi (pounds per square inch) and no greater than 80 psi. Too high of water pressure could damage any water-supplied appliances like your washing machine or dishwasher.

Most modern homes have pressure regulators mounted where the water supply enters the house. Consider having your trusted Flader plumber install one on the
water main if your home is not equipped with one, and with this in place, the banging noises should mellow out. 

Water Hammering

This is a pressure surge, or high-pressure burst of water that stops or changes direction very quickly. When this happens, the rushing water has nowhere to go and it can jam valves and pipe connections. 

It may not sound like a big deal but a water hammer can potentially damage valves and joints, which can eventually cause leaks. This can happen when a toilet valve closes or the shower is turned off quickly. 

Water hammers can occur at times in the form of much smaller bangs in your plumbing pipes with shutoff valves, so it’s important to have a professional plumber take a good look to determine where exactly it’s coming from.

Many times, your plumber will simply install a water hammer arrestor (with a spring-loaded shock absorber) in the appropriate pipe position. These redirect the “hammer” of the water after a faucet gets shut off.

Loose Pipes

If a pipe that should be securely attached to the ceiling or wall is dangling from its fixture, it’s likely to move around when water flows through it. 

To fix loose pipes, you need to anchor the pipe to a joist or stud with insulated pipe clips. 

Too Little Water in a Forced Hot Water System

Sometimes, forced hot water pipes become “airbound,” which is when too much air enters the system. This can cause a lot of banging and gurgling. 

A licensed plumber can purge the system and adjust the water temperature to
cut down on pipe expansion noises.

Copper Pipes

It’s pretty common to hear banging sounds coming from your plumbing if your home has copper piping. Copper pipes tend to expand as hot water passes through them, and if these pipes are in a tight area, they will expand and noisily rub against other structural features. 

In most cases, expanding and contracting copper pipes won’t cause a leak. Adding additional padding around these pipes can reduce the banging. 

However, unless you are remodeling, there’s no reason to spend a lot of money to add padding to your copper pipes. To stop the banging, the simple solution is to slightly lower the water temperature setting on your hot water heater.

Too Much Water in a Steam Boiler

Steam heat is notorious for causing noisy pipes. One possible cause is too much water flooding the pipes. 

To fix this, you will need to hire a reputable plumber to drain the plumbing, set the radiators correctly, and show you the proper water level to prevent banging noises in the future.

Silence Your Pipes with The Trusted Plumbers at Flader Plumbing and Heating

Most of the time the eerie banging noises you’re hearing are harmless. However, there are other times when loud noises coming from your plumbing system could signal a serious problem and can damage your pipes if ignored. Either way, the banging sound is a nuisance, and should be addressed by a trusted plumbing company.

We Help Homeowners

Flader Plumbing and Heating is uniquely suited to assist you in determining the solution that best fits your home and family’s needs. We’ve been serving your neighbors and our community for over 100 years and 4 generations. 

The Flader Difference

Only Flader Plumbing and Heating delivers:

  • The most responsive service. We’re here for you 24/7.
  • Personal attention from certified and licensed technicians.
  • The most dependable equipment and parts.
  • Money-saving maintenance agreements.
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Flader Plumbing and Heating recommends equipment, models, and brands proven to have the fewest problems and service calls. We specialize in:

Comprehensive Services

Whether you need help identifying knocking, a new water heater, or your furnace needs cleaning we are knowledgeable and provide expert service. Our professional technicians arrive on time, listen to your concerns, and answer your questions. They will recommend the right solution and deliver as promised.

Flader technicians average 15 years of experience and are EPA certified.

Expert service, quality parts, and satisfaction guaranteed. There is no reason to compromise. Call us at 847-491-6980. 

Doug Flader

Doug Flader, a fourth-generation leader at Flader Plumbing & Heating Co., upholds the company's long-standing tradition of excellence. While continuing to provide top-quality plumbing and heating services to Libertyville, Mundelein, and Vernon Hills, Doug proudly takes care of his community by supporting local youth programs around the Chicagoland area.

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Flader thrives on exceeding expectations of our residential and commercial customers.  We deliver cost effective solutions for homeowners and businesses.  Our Service Centers in Evanston and Libertyville are ready to serve.  Call us today at 847-491-6980.

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