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If you’ve ever experienced a loud banging or “thudding” noise in your pipes when turning off the tap, it’s likely you have water hammer. This common plumbing issue can be more than just an annoying noise. It can indicate underlying problems that may cause further damage to your plumbing system. In this post, we’ll discuss what water hammer is, its main causes, how to fix it, the potential costs, and when to call a plumber.
What is Water Hammer?
Water hammer refers to the loud banging or knocking noise that occurs when water flow is suddenly stopped, usually by the closure of a valve. This rapid stopping of water creates a shockwave that travels through the pipes, which is heard as a thud or bang. This noise can occur in various places around the house, particularly where there is high water pressure or fast-closing valves.
The shockwave not only causes noise but can also damage your plumbing system over time. If left unchecked, it could result in leaks, burst pipes, or premature wear on your appliances.
Main Causes of Water Hammer
Understanding the main causes of water hammer will help you identify if you’re dealing with this issue and how to approach solving it.
Pressure Issues
High water pressure is one of the most common causes of water hammer. The VBA guidelines recommend that water pressure in residential homes should be no higher than 500 kPa. If your home’s water pressure exceeds this, it can create enough force to cause water hammer when valves are suddenly closed.
Fast-Closing Valves
Some appliances, like dishwashers or washing machines, have fast-closing valves that can create a shockwave when they shut off. The quick closure of the valve doesn’t give the water time to slow down, creating the distinctive “bang” you hear.
Loose Pipes
If your pipes are not properly secured, they can move when water flow is stopped, which amplifies the noise and causes further vibrations in the pipes. These vibrations can wear down fittings, resulting in leaks or even ruptured pipes.
Quick Checks You Can Do Safely
Before calling a plumber, there are a few things you can check to identify if water hammer is the cause of your noisy pipes.
- Check Water Pressure
Ensure your water pressure is within the recommended range of 500 kPa. You can do this by using a pressure gauge, which is available at most hardware stores. If the pressure is too high, you can have a pressure reduction valve (PRV) installed to lower it to the ideal level. - Inspect the Pipes
Examine the visible pipes in your home. If any pipes seem loose or vibrating, they may need to be secured properly. This will help to prevent the shockwaves caused by water hammer from damaging your plumbing. - Look for Fast-Closing Valves
If the noise occurs only when using specific appliances, such as your washing machine or dishwasher, it could be related to fast-closing valves. You may need to install a water hammer arrestor to resolve this issue.
Fix Options for Water Hammer
There are several ways to fix water hammer, ranging from simple DIY solutions to more complex repairs that require professional assistance.
Pressure Reducing Valve (PRV)
If high water pressure is the cause of your water hammer, installing a PRV can help reduce the pressure throughout your plumbing system. A PRV regulates the water pressure, keeping it at a safe and manageable level, thus preventing shockwaves when valves are closed.
Water Hammer Arrestor
A water hammer arrestor is a small device that absorbs the shockwave created by the sudden stop of water flow. It’s installed at the end of your plumbing system where the noise occurs, and it works by using air chambers or springs to cushion the water flow.
Securing Loose Pipes
If your pipes are loose and causing the water hammer vibrations, securing them with brackets or hangers can help prevent movement. This is often an easy fix for homeowners who are comfortable with basic plumbing work.
Costs + What Affects Price
The cost to fix water hammer can vary based on the cause of the issue and the required repairs.
Fixing Water Pressure
If high water pressure is the cause, installing a PRV can cost anywhere from $200 to $600, depending on the type of system in your home and the complexity of the installation.
Water Hammer Arrestor Installation
Installing a water hammer arrestor can cost between $150 and $500, depending on the model and how many devices are required for your home.
Securing Loose Pipes
If your pipes are loose and require securing, the cost of labour will depend on how accessible the pipes are. The price can range from $100 to $400 for pipe securing services.
FAQ: Water Hammer
Here are answers to some common questions related to water hammer:
Why does my water hammer noise only happen at night?
Water hammer noises are often more noticeable at night because the home is quieter, and there is less background noise to drown out the sound. If the water hammer occurs during the day, it may be masked by the general sounds of a busy household.
Why is the water hammer noise louder after installing new tapware?
New tapware may increase water pressure or cause fast-closing valves to shut more abruptly. If this happens, the CCTV drain inspection can help locate any underlying issues in your plumbing system.
Is there a difference between water hammer in hot vs cold water lines?
Water hammer can occur in both hot and cold water lines. However, in homes with older pipes, the cold water system is often more prone to water hammer due to higher pressure and the need for repairs. Cold water systems are often the primary cause of water hammer issues.
Service Areas
We proudly service the following areas for water hammer issues and other plumbing services:
- North Shore
- Brookvale
- Narrabeen
- Belrose
If you live in any of these areas and are experiencing water hammer, contact us for a fast and reliable solution.
Book a Pressure Test + Inspection Today!
If you’re dealing with the annoying noise of water hammer in your pipes, don’t wait for it to cause lasting damage. Call now to book a pressure test and inspection. Our team can quickly assess the cause of your water hammer and recommend the best solution for your home.
