Ever shut off a tap and heard a loud bang in your pipes? You’re likely asking yourself the same thing many others do – why do my pipes bang?

Banging noises in your pipework are understandably frustrating. Most of the time, these sounds are what’s known as water hammer, a fairly typical plumbing issue that lots of homes experience.

Of course, there are other potential causes. To help you figure out the problem, this blog looks at why your pipes are banging and how you can prevent it from happening again.

What is water hammer?

Water hammer is the sound you hear when water flow is stopped suddenly or the flow shifts direction. The shift creates a pressure wave that travels rapidly through the pipes, causing them to bang and shake.

What causes water hammer?

As mentioned, the most common cause of water hammer is the sudden stopping of water flow. This usually happens when:

• Fast-acting valves in appliances (like dishwashers, washing machines, etc.) close quickly.
• High water pressure forces water to come to a sudden stop.
• Air trapped in the plumbing system creates a shockwave. 
• Faulty or worn valves fail to regulate water flow properly.

How to identify water hammer

If you’re consistently wondering why your pipes are making a loud noise, try these things:

Listen for the noise:
Is it coming from your central heating system, kitchen, bathroom, or another area?

Be aware of when it happens:
Is it when you turn off a tap, when the heating starts, or when a certain appliance is running?

What else could be causing your pipes to make noise?

If you notice a banging sound after shutting off a tap, it’s probably water hammer. But keep in mind, there could be other reasons for noisy pipes in your home, too. This can include:

Sudden valve closure:
Prompt closing and shutting of valves or taps will cause immediate stoppage of water flow, which will create a pressure wave. 

High water pressure:
A higher-than-normal water pressure can increase the force of a water hammer issue, making the banging sound louder. 

Air trapped in pipes:
Air pockets can cause rattling/knocking noises, particularly when the water is turned on or off. 

Loose fittings or pipes:
Loose pipes can move and create noise.

Faulty valves:
Deteriorating valves cause noisy boiler pipes.

Mineral deposits:
Deposits that build up inside the pipes can restrict water flow, which causes turbulence.

How to fix water hammer and noisy pipes

Fixing water hammer and noisy pipes is not an easy process. Below, we’ve included some different ways that we may check and then repair your pipes to stop water hammer and loud noises.

Secure loose pipes

Loose pipes can often move and create noise. Our engineers will use pipe clips and/or brackets to secure them to walls or floors.

By doing this, the pipes are securely fastened, which will prevent movement. 

Install a water hammer arrestor

A water hammer arrestor is a device that absorbs the shockwave created by sudden water stoppage. It’s an effective solution for eliminating banging noises in your pipework. 

Adjust your water pressure

High water pressure amplifies water hammer. We’ll first check the pressure with a pressure gauge, and if it’s too high,  we can use a pressure-reducing valve, which will keep your water pressure within the safe range of 40-60 psi (pounds per square inch) 

For more information on this, you can read our blog on how to fix common boiler problems, such as high and low boiler pressure

Bleed radiators for noisy central heating pipes

If the noise is coming from your heating system, it could be due to trapped air. We will bleed your radiators to help release this air and reduce noise. 

Replace or repair faulty valves

Old or damaged valves can cause noisy pipes. We can replace them with new, high-quality valves to solve the problem.

Drain your plumbing system

If we suspect trapped air is causing the noise, as well as bleeding the radiators, we may also need to drain your plumbing system to release any trapped air pockets. 

Use pipe insulation 

Foam pipe insulation can help dampen the noise caused by banging pipes, which would make your plumbing quieter.

A final thought

Banging noises in your pipework are your plumbing’s way of telling you something’s not quite right. 

Those strange noises can often turn into something worse if left and ignored. 

Whether it be with water hammer, noisy central heating pipes, or just a few loose fittings, understanding what’s causing the noise is the first step. 

Once you know what the issue is, you can take action to make sure your pipework stays quiet and efficient. 

At Arton Heating, we get it – nobody wants to live with noisy pipes. Our friendly, experienced team is here to help, whether you need some quick advice, reliable repairs, or a complete plumbing overhaul. Whatever the problem, we’ve got you covered.

Don’t let your pipes keep making a racket – give us a call, and we’ll help you get things back to normal.

Take a look at our page on the full range of plumbing services Arton provides for a clear overview.