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Reliance Plumbing Sewer & Drainage, Inc. Blog

Do Knocking Pipes Spell Trouble?

Let’s get straight to it–no, knocking pipes don’t automatically spell trouble. But they certainly can lead to problems if you just ignore them. And knocking pipes are easy to ignore at first. Sure, it’s a little alarming the first time you hear it, but it’s not that loud, and it’s easy to get used to.

Please don’t let yourself get used to it though! It could very well lead to plumbing problems which is the least thing any homeowner wants. Read on to learn more!

First, What Causes Pipes to Knock?

In most cases, the sound of knocking pipes is caused by a variation in water pressure within the main water line coming into your home–this is called water hammer. This may sound bad, but this pressure is actually an important part of keeping your plumbing system running as it should, keeping water moving freely between pipes and through your faucets and fixture.

When pressurized air leaks, however, water moves suddenly and violently, which causes that knocking sound that you detect, as the water travels through the length of your main water line.

So, What Should You Do?

Warn your household that the water will be shut off momentarily, find your main water shutoff, and turn it off. Next, flush all the water lines by opening all the faucets throughout your properly and flushing your toilet. With the main supply shutoff closed, water can still exit your home through your drainage pipes and sewer system–ensuring that your plumbing pipes are empty.

Once you’ve flushed all the water out, turn the main valve back on, slowly. The air chambers between and around your pipes need time to refill before water can flow freely through them again. Once you do all this, the knocking should stop!

When You Need a Plumber

If you do all this and the knocking stops, with no other weird side effects or symptoms, it may not be necessary to give a professional plumber a call. Keep in mind, however, ignoring water hammer for too long can cause plumbing joints to become loose, or cause leaks in the pipes. Keep and eye and ear out for the various signs of a leak, such as:

  • The sound of running water when no fixtures are on.
  • Warm spots on the floor indicating a slab leak.
  • A running water meter when no fixtures are on.
  • Visible signs of water damage.

You may also need a plumber if you live in an apartment or condo complex that doesn’t allow you access to the main shutoff valves. If you live in an HOA, the best thing to do is contact the property manager–or contact your landlord to find out what the next best steps are.

Lastly, be sure to call one of our plumbers if you have any questions about the information we shared above. We’re happy to help!

For expert plumbing service, installations, or maintenance contact Reliance Plumbing Sewer & Drainage, Inc. Our knowledgeable Winnetka, IL plumbers serve the North Shore and Northwest Chicago suburbs. Rely on Reliance!

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