If your pipes sound like they're humming, it's likely a water pressure issue. When the water pressure is high, it can cause the water pipes to vibrate and create a humming sound. High water pressure is more common if you have a well for your water, but it can happen with municipal water as well.
Creaking sounds in your water pipes can occur when hot water flowing through them causes them to suddenly expand as they heat up and contract when they cool again. Expanding pipes can also rub against wooden joists in the floors and walls, producing creaking noises.
The banging noise you hear is the result of vibrations in pipes. The vibrations are caused by a surge of pressure in the plumbing system when a tap or valve is opened. Sometimes, water hammer can be created when a vacuum is formed behind water.
Water hammer is a phenomenon that occurs when the flow of water in your pipes is abruptly stopped. When the cold or hot water is shut off, the pressure resonates through the pipes, causing them to bang against anything in the vicinity, such as nearby studs, joists or other water pipes.
To make matters worse, loud noises coming from your piping can actually be an indicator of a bad plumbing problem or series of plumbing problems in your pipes. If left untreated, these clogging and drainage issues can become disastrous over time.
Fortunately, noisy pipes are not often cause for concern if dealt with properly. The issue usually lies with simple issues that you can either handle yourself, or that can be dealt with through a routine call-out.
The Water Hammer Problem
The effect of the shockwaves can damage the pipes and knock them loose, and also damage taps, faucets, and appliances. Enough force from water hammer can even cause pipes to burst. If you hear rattling sounds along with the water hammer, it likely means you have pipes coming loose.
The problem could be a loose pipe that is vibrating when water flows through it, and thus the pipes make noise inside your walls. You can try to find the noisy water pipes by inspecting your plumbing in open areas of the home to see if there is significant movement of those pipes when someone turns on the faucets.
The water pressure inside your system can lead to loud noises. If the pressure reducing valve is not working properly, high pressure can build up in the pipes, causing many loud noises.
If the humming sounds like it's coming from inside the building's walls or from all taps and appliances (rather than one isolated fixture), it's probably caused by a water pressure issue.
Ticking and creaking
Plumbing systems that use copper pipes frequently produce loud ticking noises. The sound occurs when hot water runs through cold metal pipes, causing the copper to expand and rub against any surrounding wood or metal; the ticking sound in your water pipes should cease once they quit expanding.
There's air in your pipes: If your pipes make a funny moaning or whining sound when you turn on a faucet, it could mean that there is air caught in your pipes. If this is the case, something is up with your bleed-off system.
The most common cause of knocking is what's known as 'water hammer. ' This occurs when high-velocity water in a supply pipe slams into a valve which has been suddenly closed, creating a loud knock or bang, and rattling the pipe.
Popping Sounds
If you hear one or more loud “popping” sounds coming from a wall in the residence, this noise could indicate pipes bursting. When water freezes, it expands in size. Consequently, chunks of ice in a frozen plumbing system sometimes press against pipe, blocking the flow of water.
You can cure water hammer by turning off the water behind the waterlogged chamber, opening the offending faucet and permitting the faucet to drain thoroughly. Once all the water drains from the chamber, air will fill it again and restore the cushion.
The most evident warning sign of water hammer is the noise. It sounds like a loud, abrupt BANG or a THUG. It can often be accompanied by rattling in the piping. Typically, it happens more than once as the supersonic pressure wave bounces back and forth in the piping system.
A tap that makes a squealing or screeching noise likely needs the washer or stem (or both) replaced. It's normal for these parts to become worn out after many years, which makes the washer that's inside the stem vibrate when water runs past it, causing annoying screeches and squeals.
The water bangs against the pipe walls causing a distinct noise. It can cause high pressure in the pipes, high-pressure forces on pipe supports and it can cause pipes to burst damage the pipe supports and leaking at the pipe joints.
Install a water hammer arrestor
They use a built-in piston to compress air to help reduce the shockwave created by closed valves.
The banging often gets worse if the pipes aren't adequately supported or if the valves begin to wear out. The trouble is that the noise isn't just irritating. Water hammer is a key sign that damage may be occurring in your plumbing system. You must fix the cause of water hammer before it results in permanent damage.
Most often, the problem is a failed gasket in the pressure-reducing valve where water comes into the house. Replacing this valve, including the part and labor, costs less than $300, according to Connie Hodges, operations manager at Wacker Plumbing & Remodeling in Sterling (703-450-5565, www.wackerplumbing.com).
Water Hammer – A water hammer is a loud hammering sound that usually happens when a faucet or shower is turned off abruptly. The water pressure that runs through the pipes can be so strong that when suddenly halted, it can make hammering sounds that can sound like a jackhammer.
A: The knocking sounds are what's known as water hammer, caused when water flowing in pipes suddenly shuts off and vibrates with enough force to cause the pipes to knock against wood framing.