How to Fix Knocking Pipes

Have you ever heard knocking when you use the water in your home? It can sound like a chugging noise, a soft gradual knock, or a series of loud bangs! It’s not only annoying, but it could also cause much bigger issues down the road. Find out what the different causes are and what you can do to fix knocking pipes!

Air Chambers

One of the most common causes of knocking pipes is air pockets in the line. It’s easy to ignore at first, but over time the sound continues to get louder and louder. Fortunately, this issue is generally easy to fix and you can even do it yourself! The first thing you would want to do is turn off the main supply valve. Be sure to communicate to everyone in the home that this will stop ALL water from coming in. Now, flush the lines by turning on all of the faucets and flushing the toilets until the water stops running. Once the lines are cleared, turn the main valve back on slowly so that the air chambers between and around your pipes have time to refill before the water courses back into them. At this point, the knocking sound should be fixed!

Unattached Pipes

If you own an older home, you may hear knocking due to the piping not being properly secured. Plumbing codes were not as strict as they are now; therefore the pipes may not have been secured properly at the time of installation. Even if your piping was braced, the metal straps can become corroded and break free. This causes the pipes to rattle when water runs through the lines, and can bang into wall studs, floor boards, or even other pipes. This is obviously something that you would want to fix immediately as it can cause a break in the line. The simplest fix would be installing a metal strap to secure the pipe to the wall. If the pipes rattle throughout the walls, a foam insulation may need to be applied.

High Pressure

The water pressure in your home may be too high, causing the pipes to make banging noises from the force of the water rushing through them. A certified plumbing technician can help you measure the water pressure in your pipes to determine if it exceeds 80 psi per the Florida plumbing code. If it’s over that amount, you may need to install a pressure regulating valve to control the amount of water that enters your home.

Water Hammer

One of the most serious problems of knocking pipes is known as “water hammer”. This is caused by excessive water velocity and air in the pipes. When you shut water off, you put a sudden stop to the movement of water through your pipes. This causes a ricochet effect where the water actually slams back and forth through your pipes until the water’s energy is dispersed. (See picture below)

To fix water hammer, you will most likely have to install water hammer arrestors to reduce the shock of ricocheting water.

If you’re having any of the issues noted above, give Aztec Plumbing a call! We would be happy to help by sending a trained technician to your property who can diagnose and resolve the issue once and for all. Protect your home and have peace of mind – Call Aztec today!