Professional plumbers use the term water hammer to describe a fairly common issue that happens with some plumbing systems, especially in older homes. The water hammer effect is when you get a fairly loud banging or knocking noise coming from your plumbing system. The reason that this noise occurs is a result of a pipe banging into something else like a wall stud or floor joist as soon as you turn a faucet or shower off.
An even more common issue is repeated water hammering each time your washing machine or dishwasher finishes a rinse cycle and the water shuts off. This guide will explain all you need to know about the water hammer effect. It includes what causes it, the damage it can potentially do to your plumbing and what options you have for preventing it.
What Is the Water Hammer Effect?
In technical terms, water hammering occurs due to a phenomenon known as hydraulic shock. This is when the water flowing through a pipe suddenly hits a closed valve and temporarily flows in the opposite direction. That means as soon as you shut off a faucet or shower and the valve closes, the water produces a powerful shockwave that bounces off the valve and causes the water to travel in the opposite direction back through the pipe.
One thing you may be surprised to learn is that this type of shockwave in water travels at almost the speed of sound and is far more intense than a shockwave traveling through the air. The shockwave is very powerful and travels quickly. That means it can sometimes cause a pipe to move or shudder so much that it results in the pipe banging against something else and causing a water hammer.
What Issues Can Cause Water Hammering?
The most common reason you’ll hear a water hammer when shutting off a certain plumbing fixture is that the pipe feeding that fixture isn’t fully secured. The fact that you get such a powerful shockwave when shutting a plumbing fixture off is why all of the water lines in a building have so many brackets and braces that hold them securely in place.
If a water line doesn’t have enough bracing, it can end up banging against whatever it’s supposed to get secured to each time the fixture it supplies gets shut off. Over time, the shockwaves you get from repeatedly shutting the water off each day can also result in some of the bracing starting to come loose. Therefore, the pipe will no longer have a full secure connection. This is why water hammering is so common in older houses that have never had the original plumbing replaced.
If a plumbing system has an issue like a leaky water line or a faulty pressure-relief valve, it can also result in water getting inside some of the pipes. The trapped air essentially creates a vacuum that temporarily blocks water from flowing, meaning the water encounters a barrier and creates a shockwave when it flows backward. This issue is why many residential plumbing systems have air-release valves in certain places. For example, this may occur on pipes that run a much longer distance or when there’s a significant change in elevation from one end of a pipe to the other.
Another time you’ll often end up with a water hammer effect is when the stop valve in a faucet or other plumbing appliance is worn out. In this situation, you may hear water hammering when the water is running instead of only when you shut the fixture off. Worn-out stop valves typically happen because the internal “packing” comes loose or if there is a worn washer. Either issue can cause the valve to rattle as water flows through it. This rattling can sometimes be strong enough to make the pipe connected to the valve shake and bang.
Modern washing machines and dishwashers are especially notorious for causing water hammering. When you turn off a faucet or shower, the flow of water first gets temporarily reduced before getting completely blocked off. That means there is much less of a shockwave and thus less of a chance of a water hammer occurring as long as the pipe supplying that fixture is secured properly.
The issue with dishwashers and washing machines is that they instead have electronically controlled solenoid valves that close in a split second. That means all of the water instantly hits a barrier, resulting in a much bigger shockwave being created and the pipe feeding the appliance shuddering and knocking far more. Luckily, this issue is something you can mostly prevent just by adding extra brackets and bracing so that the pipe is secured more tightly.
You’ll also often experience much more frequent and more severe water hammering if your water pressure is too high. That’s just because high water pressure means the water flows through your pipes with more force, resulting in a more powerful shockwave being produced when it hits a barrier and switches directions. This is one of the many reasons why it’s worth investing in a pressure-reducing valve if your plumbing system doesn’t have one, or having your old valve replaced or repaired.
Why Water Hammer Isn’t Something You Should Ignore
While constantly hearing your pipes banging and knocking is definitely annoying, the issue goes far beyond merely being a nuisance. The main concern with water hammering is that there’s an extremely high chance it will lead to your plumbing system developing a major leak. Or you may need to frequently pay to have minor leaks repaired.
Repeatedly knocking against an object can cause abrasion that weakens and thins a pipe over time until it finally develops a hole and starts leaking. If the pipe is severely weakened, it can even end up bursting and majorly leaking. Another issue you can encounter when a pipe continually bangs and knocks is that it can result in an elbow or joint coming loose. This will also result in a serious flood if you can’t shut the water off immediately.
If you have frequent water hammering throughout your house, the issue can eventually get so serious that you’ll need extensive pipe repair or may need to have your home partially or fully repiped. That means potentially paying several thousand dollars to fix your plumbing along with needing to have quite extensive demolition and renovation work performed. You also need to consider all of the water damage that could occur whenever your plumbing leaks.
Contact Us Today
Ribbs Plumbing Services is a premier plumbing company dedicated to providing exceptional water, drain, sewer, septic system and gas line services. We have experts in residential and commercial plumbing who can professionally manage your project from start to finish. Whether it’s overcoming water hammer issues, detecting and repairing plumbing leaks or whatever else you need, you can trust us to provide top-notch, customized solutions at fair, competitive prices.
We always start by providing a no-cost consultation and will make sure you fully understand your options. From there, we’ll use the best, most cost-effective methods, parts and equipment to ensure everything is done exactly as it should be. If you’re looking for the most reliable plumbing services in San Jose, contact Ribbs Plumbing Services today.
