What Is Water Hammer?
Water hammer occurs when flowing water suddenly stops or changes direction.
Because water has momentum, when a valve closes quickly the moving water creates a pressure shock inside the pipe.
This shock wave travels through the plumbing system and causes pipes to shake or bang against framing.
That sudden pressure spike is what creates the loud knocking sound.
What Causes Water Hammer?
Several issues can lead to water hammer in residential plumbing systems.
Fast-Closing Valves
Modern appliances such as washing machines and dishwashers use solenoid valves that shut off water quickly.
When the valve closes instantly, water momentum creates pressure shock.
High Water Pressure
Homes with water pressure that is too high are more prone to water hammer.
Excess pressure increases the force of the shock wave when water flow stops.
Loose Plumbing Pipes
If pipes are not properly secured inside walls, even a small pressure shock can cause them to bang against wood framing.
Missing Water Hammer Arrestors
Water hammer arrestors are small devices that absorb pressure shock.
Older homes may not have them installed.
Why Water Hammer Should Not Be Ignored
While the noise is annoying, the bigger concern is pipe stress.
Repeated pressure shocks can lead to:
- Pipe joint failure
- Damaged valves
- Leaking fittings
- Cracked plumbing components
Over time, water hammer can shorten the lifespan of your plumbing system.
Signs You Have Water Hammer
Common symptoms include:
- Loud banging when faucets shut off
- Pipes shaking or vibrating
- Noise after appliances fill with water
- Sudden pipe movement inside walls
If these sounds happen frequently, the system likely needs adjustment.
How Water Hammer Is Fixed
The correct solution depends on the cause.
Installing Water Hammer Arrestors
These devices contain air chambers that absorb pressure spikes when valves close.
They are commonly installed near washing machines or appliances.
Securing Loose Pipes
Pipes inside walls may need additional supports or brackets to prevent movement.
Adjusting Water Pressure
If pressure is too high, installing or adjusting a pressure-reducing valve can help stabilize the system.
Repairing Faulty Valves
Old or damaged shutoff valves can contribute to pressure shock and may need replacement.
Preventing Water Hammer in Cambridge Homes
Preventative plumbing maintenance can reduce the risk of water hammer.
Helpful steps include:
- Monitoring water pressure
- Installing hammer arrestors on appliances
- Ensuring pipes are properly secured
- Addressing unusual noises early
Small fixes now can prevent expensive repairs later.
Final Thoughts on Water Hammer in Cambridge, ON

Water hammer is a common plumbing issue that many homeowners ignore until the noise becomes severe.
But those pressure shocks can slowly damage your plumbing system.
If you hear banging pipes in your Cambridge, ON home, it’s worth investigating before it turns into a leak or burst pipe.
Early diagnosis keeps your plumbing running smoothly and quietly.
