Fixing a toilet that fills up with water when it's flushed

If you're dealing with a toilet that fills up when you flush it, then you're probably panicking, simply hoping the water doesn't overflow! In this guide we'll cover why your toilet might have drain issues and home remedies to try.

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Facing a toilet filled up with water in the middle of the night is never good. Imagine the impending doom as the toilet won't stop filling up. Panic will inevitably occur!

To learn how to identify your toilet flushing issues and how to fix them, why not read on?

Sometimes simply knowing when to contact a reliable local plumber is the most important part.

Why is my toilet filling up when I flush?

If it fills up with water instead of flushing as usual, there could be several culprits.

Once you know the why, you can deal with the how.

Let's explore the causes of a toilet filling up with water once you flush it.

1. Clogged drains

A clogged drain is one of the most common causes of a toilet filling up with water.

Anything big enough to cause obstruction can prevent water from flowing freely. This causes the water to back up when flushed.

Think about it: the water has to go somewhere. Need more help?

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2. Water supply issues

Any problems with your water supply valve or a malfunctioning fill valve can lead to inadequate water levels.

Some of the common causes of water supply issues include:

• Leaks

• Overuse

• Broken flush tube

• Evaporation

Insufficient water levels don't just interrupt flushing. They often lead to a toilet filled up with water.

3. Faulty flapper

Yes, it might sound funny. But when your flapper becomes faulty, it doesn't feel funny.

The rubber seal that controls the water flow from your tank into the bowl is the flapper.

When your flapper is old, worn or damaged, it makes your toilet constantly run. Of course, this results in excess water, which is why your toilet fills up when flushed.

Sound like you might someone professional to have a look for you?

Why won't the water go down when I flush?

When your toilet keeps filling up when flushed, other common causes to look out for include:

• Blocked rim jets

• A faulty float

• Broken handle and chain

• Flushing mechanism issues

Sometimes the cause of a problem might be something seemingly unrelated. For example a problem with the button or chain itself, rather than the flush mechanism.

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How do I stop my toilet from filling after flushing?

If your toilet keeps filling up when flushed, we have some helpful solutions you'll want to try.

1. Check for obstructions

Inspect the toilet bowl and drain hole for any visible blockages. For example:

• Toilet paper

• Flushable wipes

• Foreign objects

• Broken ceramic

• Loosened valves

Get to work with a plunger to dislodge any clogs in the toilet drain. You can try a toilet auger (a plumber's snake) for deeper blockages.

2. Test the flush

Try to observe the water flow while you flush the toilet.

If the toilet doesn't drain and fill as usual, there could be a deeper problem.

It is important to call a trusted plumber if you have flush issues you can't figure out.

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3. Clear the drain line

If you've checked and plunged for apparent blockages with no luck, try snaking the drain line.

It might help to clear any stubborn clogs.

Or, if you'd prefer a less hands-on approach, try a drain-cleaning product specifically designed for toilets.

4. Look at the fill valve

You can also try adjusting the fill valve. Turn the adjustment screw of the fill valve to change the water level.

You can check your toilet's instruction manual for help if you need it.

5. Search for sediment buildup

If your toilet fills up with water and then slowly drains, the problem is probably with the rim.

When the rim jets get clogged with sediment, the water pressure drops. Then, there isn't enough force to push the bathroom's contents down the drain.

Use a small mirror to find these mineral deposits - they look like light or colour across the holes.

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6. Check your water levels

Low water levels in your tank are common causes of toilets filling up with water when flushed. They can also cause slow-draining toilets.

Check the flush tube for cracks and bends that lead to leaks. If you notice damage, install a new one for an easy fix.

If you've exhausted all possible avenues and your toilet still won't flush, it's time to call a plumber to take a look.

Tips for unclogging a toilet with a plunger

Knowing how to use a plunger effectively can mean the difference between a clogged and unclogged toilet.

If you don't have time to wait for a plumber, you can try working on your technique to unclog your toilet.

• Act quickly - Remove the lid, find the flapper, and press it to stop the water (then turn off the valve)

• Choose the right plunger - Pick a cup style that gets you a good seal between the plunger and bowl

• Warm up your plunger - Pop it in hot water for a few minutes before using it (if time allows) to create a better seal

• Perfect the technique - Plunge firmly up and down, maintaining an even push and pull

If you unclog the toilet, water will rush from the toilet bowl. Then, turn the water back on and try to flush normally.

You might have a bigger problem further down the drain if these tricks don't work.

Find toilet repair services near me

If your toilet isn’t working properly or is wasting water, search for toilet repair near you with Checkatrade. All our tradespeople are committed to quality, so you can be sure of a job done right.

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Finding plumbers to deal with your broken toilet

Hopefully, these home solutions for toilets filling up with water will get your toilet flushing normally.

But it's important to know when to call in for professional help. When none of these DIY solutions works, a plumber can get your flush like new.

Not sure where to start? At Checkatrade, we can help put you in touch with reliable and local tradespeople like plumbers and toilet specialists.

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