If you hear a ruckus when the toilet flushes, that means there's something awry
Noises from your plumbing after flushing the toilet are annoying, if not alarming. Not to mention, it can be pretty embarrassing to have your toilet notifying the entire house with every flush. So, what’s the deal with all the noise from the pipes when the toilet flushes? Let’s take a look at why your toilet makes noises after flushing and what you can do to fix the problem.
1. Water Hammer
A knocking or hammering noise in your pipes is a telltale symptom of water hammer. This phenomenon can also sound like a loud thud after flushing the toilet. When you flush the toilet, it opens a valve to allow more water in. Water hammer happens when the valve suddenly shuts off, resulting in water with no place to go. This incident causes the excess water to hit the walls of your pipes at high speed, resulting in a rattling or hammering sound.
How to Fix
Water hammer is a noisy nuisance that can damage your pipes over time if left unaddressed. You can fix the issue by hiring a local plumber to install a water hammer arrestor, which absorbs the shock of the sudden rush of water.
2. Ghost Flushing
If your toilet seems to be mysteriously flushing on its own, especially at regular intervals, the culprit is more likely to be a faulty flapper than a ghost. When the flapper at the bottom of your toilet tank isn’t sealed properly, water will slowly seep out of the tank into the bowl. Once the tank float sinks below a certain level, the water switches on, and your toilet will flush on its own.
How to Fix
To determine whether the flapper is the problem, add a small amount of food dye to the water in your toilet tank and wait about 30 minutes. If any of the food coloring travels to the bowl, the flapper is the issue. You can easily replace a toilet flapper in 30 minutes or have a professional plumber address the problem.
3. Your Toilet Hisses
A persistent hissing noise is a common problem in older toilets that can have a variety of causes:
The leaking is caused by a deteriorating rubber flapper or valve seal.
A misadjusted float or fill valve causes water to drain into the overflow tube.
A malfunctioning chain is lifting and letting water run continuously.
An uneven water supply is running from the water flow lines to the toilet.
How to Fix
Since there are many reasons a toilet might be hissing, the first step is to properly diagnose it. Start by examining the water supply valve at the base of the toilet. Adjust the flow to see if the hissing stops or the toilet flushes better. If that doesn’t solve the issue, turn off the water supply and open the lid to examine each part.
The float and fill valve should be set below the fill line so that water doesn’t go too high and continuously drain into the overflow tube. Adjust if not.
The flapper should create a watertight seal over the flush tube at the bottom. If sediment is built up on the flapper, remove it and see if an improved seal stops the hissing.
The fill valve seal at the top of the tank may also have sediment buildup. Remove it to see if the hissing stops.
If any of these components are deteriorated, small holes may be the source of a leak and the hissing sound. Take your damaged part or parts to the hardware store and find a matching part to replace each of them. If your toilet still hisses, your problem may need the help of a professional plumber.
4. Groaning or Vibrating Noise When Flushing the Toilet
When you hear a vibrating noise from your pipes when the toilet flushes, this usually points to an issue with the fill valve. This piece is the part of your toilet that refills the water tank. It might also sound like a foghorn or groaning noise that continues for around 30 seconds after you flush. Once the toilet tank gets filled, a small diaphragm in the fill valve pushes down and cuts off the water flow. This diaphragm is made of soft, flexible material—typically rubber—which creates a tight seal to prevent the tank from overfilling. Over time, the diaphragm can become stiffer and less malleable. This change causes it to rattle around when the incoming water hits instead of staying tightly sealed as it normally would. If you’re hearing a humming or vibrating sound, that’s likely the source.
How to Fix:
You can diagnose a fill valve issue by following these steps: 1. Take the lid off the toilet tank 2. Flush the toilet 3. Lift the ball float to cut off the flow of water If the sound stops, there’s an issue with the fill valve. Once you’ve pinpointed the problem, you can get rid of that vibrating noise by replacing the fill valve. This task is a simple DIY toilet repair if you have the skills and tools. The new valve should have instructions for replacement. If you’re uncomfortable handling this alone, a local plumber can always assist you.
5. Rushing Water
Hearing a running water noise usually means the tank is constantly filling. This sound might indicate a leak within the tank, resulting from a few different causes.
A running water noise when flushing the toilet might mean there is water leaking from the tank into the bowl. Either way, it’s important to address this issue to prevent your toilet from wasting water. It could also point to one of these issues:
Your fill valve is faulty.
The float in the toilet tank is set too high.
The chain that connects to the toilet handle is too tight.
How to Fix:
First, remove the lid from the tank and check if the float is higher than the fill valve. If so, then adjusting the float should fix the issue. If that doesn’t fix the problem, look at the chain. It might be too tight, preventing the flapper from sealing the hole properly. There may also be too much slack, causing the chain to tangle. If you notice any of these issues, try adjusting the chain by removing its clip to the toilet handle and increasing or decreasing the length. Not having any luck with these fixes? There might be parts that require replacement. Call in a plumber to give a proper diagnosis.
6. Gurgling
If your toilet is gurgling, the source of the sound can be tricky to trace and remedy without serious plumbing experience. Several issues could be causing the gurgle:
A blocked sewer drain
A blocked vent stack
A blockage in the toilet itself
How to Fix
Do not attempt to fix a gurgling toilet on your own unless you have significant plumbing experience. Avoid using the toilet, shut off the water supply, and hire a professional plumber as soon as possible. This method is the best way to keep the problem from developing into a more serious plumbing issue.
What to Do About Noisy Pipes When Flushing the Toilet
Luckily, a noise from your pipes when the toilet flushes isn’t always a death rattle. Many of these issues are repairable by fixing or replacing small parts. However, if there are issues with leaking, efficient water use, or broken components, these are good reasons to replace your toilet. Get in touch with a professional plumber to learn your options.
