Helpful Tips: How To Detect A Toilet Leak And Fix It

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Working on your own home instead of hiring a plumber or tradesperson can save you so much money. But what if you’ve never worked on a toilet before? What if you don’t know how to repair a leak or deal with a running toilet? We think that with a bit of guidance and some courage, you could be doing your own repairs and detecting and fixing toilet leaks. 

So here, we are going to go through some of the basics of a toilet, the different types, and how to detect and fix a toilet leak. If you want to gain more knowledge about repairing your own toilet, then you have come to the right place! Let’s get started on the different types of toilets you will find in a bathroom or powder room. 

Table of Contents

Types of Toilets

One Piece ToiletsToilets are made up of two key parts: the cisterns (or water tank) and the toilet bowl. Sure, there are other elements such as the flush and the waste pipes, but essentially they are contained within either the tank or the bowl. A one-piece toilet is a toilet that has been molded into one single piece, so the bowl and tank are one formed block rather than two separate units. 

Two Piece Toilets

A two-piece toilet is where the tank and the bowl are two items that need to be installed separately. This is a more traditional style of toilet, but it does come with drawbacks. For example, with two pieces being independently fitted, it makes more hotspots for leaks. They are, however, cheaper in the long run as you only need to replace one element rather than the whole unit. 

Wall Hung Toilets

Wall hung toilets are also known as concealed toilets as they hide the cistern behind a wall. This leaves only the bowl and the flush buttons showing and creates a much sleeker finish. Wall-hung toilets aren’t as easy to install as a one-piece or two pieces, but they are very stylish and make the extra work well worth it. 

Pressure Toilets

Pressure toilets are toilets that use an electric motor (or, on some occasions, a high pressured flush system) to force the waste through to your septic system. These are ideal for areas where you are installing a bathroom that is underground or in a tricky location. They can cost more than a standard toilet, but this is to be expected when you consider the extra technology that comes with it. 

How to Detect A Toilet Leak

A puddle on the floor near your toilet can be worrying, especially when you can’t tell where it is coming from. Here we will run through how to detect where your toilet leak is coming from. 

Start at the top and work down

The water inlet that supplies your toilet with water is usually near the top of the water tank and is the first place you should look for a toilet leak. This pipe often becomes clogged with limescale or calcium build-up, and these blockages might be causing a leak. Check this inlet pipe first. 

Next move to where your cistern meets your toilet bowl. Some screws usually connect this, and if they aren’t tight enough or the washers around them have perished, you might find a leak. 

Also, check the flush outlet (which is known as the flapper and let the water into your toilet bowl). IT should have a rubber seal around it that fits nicely into its location. If this seal has perished, then your system won’t have a proper seal and will be leaking. 

Working downwards, look around the toilet bowl for any cracks or pressure points that might be weeping water. This rarely causes a leak, but it is worth checking just in case your toilet is very old. 

Finally, check your waste outlet pipe. Again, this has a rubber or wax seal that, if not inserted correctly or worn away, will cause a leak onto the floor. 

Ensure there is only one leak

The problem with water is that it creates pressure. If your toilet system isn’t perfectly balanced with this pressure, then it redirects to other places. In other words, if you have an undetected issue in your toilet system somewhere, it may divert pressure elsewhere to create a new problem. Check your whole toilet over, even if you think you have found a leak. 

If necessary, use dye

One handy way to easily tell where your leak is coming from is to use dye. Start by placing a few drops of food coloring or dye in your toilet bowl and give it half an hour to see if the dye comes through from your leak. If your leak doesn’t change color, then flush the toilet and try some dye in the cistern. If this doesn’t change the color of the leak, then you know it is between your water system and your toilet that has the leak. 

How to Fix A Toilet Leak

  • Turn off the water
  • Empty the toilet
  • Take your toilet apart
  • Replace or seal your leak
  • Test your leak with a jug of water
  • Turn the water back on


“My toilet has made a puddle on the floor, where is it leaking from?”. By referring to our section on how to detect a leak, you should be able to isolate this problem. Remember to work from the top down and if you need to use a dye to help you identify the leak more easily. 

“My toilet is dripping from the inside, is this a leak?”. Your toilet might be running, which is where a leak occurs inside the toilet rather than out. This can mean wasted water and irritating noise. Most often, a running toilet is an issue with the flush mechanism or the water tank. Firstly, check the tank is adequately aligned with the toilet bowl and tightly secured. If this doesn’t solve it, then check your ball cock to ensure that it freely measures the water level. If this is stiff, then you will want to lubricate it to free it up a little. 

“My leaking toilet smells foul, what is it?”. If you have a leak that doesn’t smell too great, then you more than likely need to look at your waste outlet. There are two main causes for waste outlet leaks, a perished rubber seal and a blockage. A blockage is pretty straightforward to deal with, although not fun. If you can’t dislodge the blockage from the toilet bowl, then you might need to take the trap off and empty it out manually. If there is no blockage, then you should replace your wax ring. This ring is imperative for keeping a tight seal between the toilet and the waste pipe and can perish over time. By replacing it with a new one, it will solve the leak. 

When to Replace A Leaking Toilet

While we are huge advocates for repairing household items, occasionally, you might need to replace them. Over time toilets can wear, and items within it can start to work less effectively. Inner coatings can wear away, and the older the materials become, the more likely they are to develop pressure points. If you have a toilet that is very old, then we recommend replacing it for a newer, more water-efficient model that will be easier to maintain and better for the environment. 

As you can see, detecting and fixing toilet leaks isn’t as difficult as you might think! No longer will you have to call for the plumber and pay out hundreds of dollars. You can repair your toilet yourself by following these simple steps.

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