If you find some water on the floor of your bathroom (close to your toilet) and it causes you worry, you can be sure that this problem has numerous possible causes.
After ruling out the most obvious (poor aim), there are some things to consider before assuming it might be from the seal on the sewer line.
This is typically less expensive than the possibly costly likelihood of your toilet bringing out wastewater.
Fixing Toilet Leaks: Condensation
The likely most common reason for much water on the bathroom floor is the action of condensation of water on the external side of the toilet tank and subsequent dripping on the floor.
This is mostly known as tank "sweating."
Tank sweat/condensation is due to the variance in temperature of water within the tank (often very cold) and that of the air outside of the tank within the bathroom (usually steamy and warm).
This phenomenon mostly occurs in the hot summer months than in the winter, but can happen at any time under the right conditions.
Fixing Toilet Leaks: The Tank
After checking to see that the cause of the problem isn’t tank sweating, then the immediate alternative is to check that the tank itself isn’t leaking.
It is quite easy to do this.
Simply remove the lid of your toilet tank (apply extra care here, as the tank lid is very fragile and can be heavy and also slippery when it is wet) and put in some organic coloring (like food coloring) into the water in the tank.
Do not flush soon after the coloring is added, but wait a while for the color of the water in the tank to change and settle.
Check the water on your bathroom floor after 10-15 minutes to see of it is a similar color as the water inside the tank.
If you notice any colored drips discharging from the tank externals, then you can be sure that there is water leakage from the tank since you only have the colored water there.
Next, you will need to detect where the water leakage is from.
You can easily observe any cracks in the tank being highlighted by the colored water.
This is also good to locate any leakages around the rubber seals and bolts between the bowl and tank or even from the foam gasket where water is allowed into the bowl.
Fixing Toilet Leaks: The Bowl
Bowl leaks can also be detected using the colored water trial described in step 2.
If the leakage seems to originate from between the bowl and tank, close to the center, new washers for the bolts (tank-to-bowl) or a new sponge gasket (tank-to-bowl) may be what you need.
Leaking that occurs from the tank-to-bowl sponge gasket, it will be more frequent while flushing the toilet.
If it is leaking from the washers and bolts, then the leakage can mostly seem to be nearer to the bowl sides, close to the edges and further from the center, then again not all the time.
Fixing Toilet Leaks: The Fill Valve
Ensure to inspect the shank gasket which has the fill valve attached to the tank.
The fill valve or “ballcock” allows water into the tank. The shank gasket is connected to it inside the tank.
Again, the colored water test can also be used to detect this type of leakage.
Inspect the tank for likely cracks near or around the gasket. If there are no visible cracks, you may simply ensure the shank nut under the tank is tightened to stop the leakage.
We recommend a 1/4 turn tightening at a time as you check to see whether the leakage stops. If the leakage continues, then a replacement gasket is required.
Fixing Toilet Leaks: The Refill Hose
If it seems like the leakage is from behind, close to the tank’s top, then check that the refill hose has not detached from the overflow hose on the flush valve.
Fixing Toilet Leaks: Shut Valves & Supply Lines
Ensure that there is no water leakage in the piping at the back of the shut-off valve close to the wall.
If there is, then you may need to replace the valve (though you may be able to tighten it, depending on the kind of pipe and valve it is).
Inspect the supply line for drips of water from the nuts at the ends where it connects to the fill valve inlet and shut-off valve on the other end. If your supply line is rigid, then you may be able to replace the washers.
Fixing Toilet Leaks: Under the Bowl
If you are certain that it is wastewater on your floor (from the color and obvious smell), then you are experiencing something more.
Though you may not see repeat overflow, the water is likely recycling through the initial point of lowest resistance – beneath the toilet.
Most times, water from the bathtub or shower will pool at your toilet area, being that it’s the lowest bathroom fixture.
With this it may seem as though water is leaking from the toilet when actually it is due to something much simpler and cheaper.
You can choose to add one or two throw rugs to checkmate this.
Fixing Toilet Leaks: Small Cracks
Sadly, there is no dependable means of repairing cracks on a porcelain fitting. Here, you will need to replace your tank or the entire system.
Please read our related article: Toilet Flapper Replacement