Can Water Hammer Burst Pipes?

When you hear loud banging or knocking in your pipes, it can be a water hammer. Water hammer in pipes is a plumbing issue that happens when flowing water is suddenly forced to stop or change direction. This sudden change creates pressure waves that can shake and rattle your plumbing system.

In this article, we will explain what water hammer is, why it occurs, and the common causes behind it. We will also cover practical steps you can take to fix water hammer yourself, and when it is best to call a professional plumber. Early attention to water hammer can protect your pipes from damage and help you avoid expensive repairs.

What Is Water Hammering

Water hammer, also called hydraulic shock, is the banging noise you hear when water flow stops suddenly inside pipes. It happens when fast-moving water hits a closed valve, creating a pressure wave that vibrates through the system.

In many modern homes, water hammer is controlled by built-in features such as air chambers or water hammer arrestors. These components work as buffers, helping to absorb sudden pressure changes in the plumbing system. This prevents hammering pipes, where the shockwave causes loud banging or knocking sounds. In older homes, or where these protective features are missing, faulty, or installed incorrectly, the pressure has nowhere to go. As a result, the pipes may vibrate or rattle, creating a hammering effect.

What Causes Water Hammering in Pipes?

Water hammer is usually the result of a few key issues in plumbing systems. While some causes relate to how the system was installed, others come down to how the water supply is used.

Here are the main triggers:

Sudden Valve Closure

When a valve shuts quickly, like on a washing machine or dishwasher, the flow stops instantaneously. Water still moves and slams into the closed valve. Since water can’t compress, that energy creates a shockwave, often heard as a knock.

High Water Pressure

Excessive pressure can make the shockwave much stronger. High pressure amplifies the force behind the surge, increasing the risk of knocking and even damage

Loose or Poorly Supported Pipes

When pipes are not secured properly, even minor shockwaves can cause them to shake or bang against surrounding surfaces. Poor support makes the sound worse.

Trapped Air or Blocked Air Chambers

Air pockets in plumbing can either help absorb pressure or worsen it. If air chambers are blocked, filled with water, or absent, there’s no cushion to absorb the surge. This often leads to repeated hammering noises.

Ball-float Valves in Tanks

In some tanks, the ball-float valve rocks up and down as water flows in. This repeated opening and closing can create pressure waves that echo through the pipes. Plastic tanks may flex more, increasing the risk of water hammer.

Can Water Hammer Cause Pipe Damage?

Water hammer might seem like just a noisy inconvenience, but it can lead to real problems if ignored. Over time, the repeated pressure surges place stress on your plumbing system and can slowly cause water hammer damage.

Each time the water slams into a closed valve, that energy travels through the pipes. This can loosen joints, weaken fittings, and gradually wear down the internal structure. In some cases, it may lead to small leaks. In more serious cases – especially where the system is old or the pressure is too high—it can result in pipe damage or even a burst.
Pipes made from rigid materials like copper or PVC are particularly at risk. These materials don’t absorb shock well, so the impact builds up over time. That makes them more prone to cracking.

If you’re asking, will water hammer damage pipes, the answer is yes – especially if your plumbing system is older or under strain. Homes with poor pressure control or loose pipework are more likely to be affected. If you hear frequent banging or knocking, it’s worth having it looked at. Fixing the issue early helps avoid costly repairs later on.

How to Fix Water Hammer in Water Pipes

Water hammer doesn’t always mean a major repair is needed. In many cases, the issue can be managed with simple steps, especially if identified early. The right approach depends on what’s causing the noise and how severe it is.

DIY Fixes

If the water hammer is mild and your plumbing is in good condition, a few basic adjustments can help reduce or stop the noise:

1. Drain and refill your system

   Turn off the main water supply, open all taps to drain the pipes, then slowly turn the water back on. This can restore the air pockets in your system that help absorb pressure.

2. Secure loose pipes

   Use clamps, brackets, or pipe insulation to hold pipes in place and minimise movement. Pipes that aren’t properly supported tend to vibrate when pressure changes suddenly.

3. Install tap or valve flow restrictors

   Slowing down the water flow into appliances like washing machines or dishwashers can help reduce pressure surges.

These steps are suitable for newer plumbing systems or where the water hammer is occasional and not linked to any visible damage.

When to Consider Professional Solutions

If the problem keeps coming back or your plumbing is older, it may need more than a quick fix. Professional plumbers can assess the system and suggest long-term solutions such as:

1. Fitting water hammer arrestors

   These devices absorb pressure changes and prevent banging by cushioning the water flow.

2. Installing a pressure-reducing valve (PRV)

   A PRV lowers the overall pressure in your plumbing system. This is especially useful in areas with high mains pressure.

3. Upgrading outdated pipework

   In older homes, pipes may be too small or worn out. Replacing them with pipes better suited to current flow demands can make a big difference.

Licensed plumbers have the tools and knowledge to identify the underlying issue and provide tailored solutions. Professional repairs not only reduce noise but also help protect your system from long-term wear or damage.

Need Help Fast? Call an Emergency Plumber in Melbourne

If you hear persistent banging noises or notice signs of plumbing problems, it’s wise to seek expert advice. A professional plumber can accurately diagnose the problem’s cause and recommend tailored solutions. VCM Plumbing is here to help with every plumbing emergency – not just water hammer issues.

We specialise in diagnosing and repairing problems like blocked drains, burst pipes, and hidden leaks. Our licensed team has been trusted by Melbourne homeowners for over 20 years. We use advanced methods like CCTV drain inspections and hydro-jet cleaning to diagnose and fix issues quickly.

We also provide comprehensive leak detection services. Using modern equipment, our technicians can locate both visible and hidden leaks – whether they’re behind walls, under floors, or in outdoor areas like gardens and driveways. To speak with a local expert or book a service, call us on 0438 073 355 or email us at info@vcmplumbing.com.au.

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