11 Ways to Fix a Sweating Toilet Tank

Last Updated on August 1, 2023 by toilethaven

How Do You Stop a Toilet From Sweating?

Water on the surface of a toilet is very undesirable. It means that your toilet is either leaking or sweating. Both of these conditions, if not fixed early on, will definitely ruin your bathroom floor and subfloor, which will lead to more expensive repairs.

A sweating toilet is caused by the difference in temperature between the cold water inside the toilet tank and the warm and humid bathroom surrounding it. When hot and humid air comes into contact with the cold body of the toilet tank, it is cooled down, and condensation occurs. Moisture forms on the tank and starts dripping on the floor.

There are several ways to stop a sweating toilet. Some may be permanent, while others might be temporary or quick fixes.

Ways to Stop a Sweating Toilet

  1. Take cooler and shorter showers
  2. Use an exhaust fan while taking showers
  3. Dry tubs/shower walls after showering
  4. Install air conditioning
  5. Use a toilet drip tray
  6. Close bathroom windows on hot days
  7. Keep the toilet tank empty
  8. Insulate the toilet tank.
  9. Buy an insulated tank or toilet
  10. Buy a tankless toilet
  11. Install an anti-sweat valve

Is My Toilet Leaking or Sweating?

Before you go ahead to fix a sweating toilet, you need first to establish that your toilet is actually sweating and not leaking. A toilet that is leaking between the tank and the bowl can be confused for a sweating toilet.

With a sweating toilet, the toilet tank is wet all around it, but a toilet that is leaking will be letting water out between the tank and the bowl, and therefore the tank will remain dry. It is, however, possible that a toilet tank will be sweating and leaking at the same time.

To be sure about that, put a dye tablet or food color inside the toilet tank and wait for about 10 minutes. Check for the dye or food color between the toilet tank and the bowl as well as inside the bowl.

If you see the color between the tank and the bowl, then your toilet tank is leaking. On the other side, if the toilet is running, you will see the color inside the toilet bowl.

A running toilet is a result of a faulty toilet flapper or fill valve. If a toilet is leaking or leaking and is sweating at the same time, the sweating will be severe since cold water is constantly flowing into the tank, therefore, accelerating the condensation.

A leaking toilet tank is caused by a toilet tank to bowl gasket that is no longer sealing. If that is the case, this is how to replace a toilet tank gasket. If you have a running toilet, you can replace the fill valve and the flapper. This is how to replace a toilet fill valve, and this is how to replace a toilet flapper.

Temporary Ways to Fix a Sweating Toilet

These methods might not completely stop the toilet tank condensation but will help to lessen it or prevent its damages

1. Keep the Toilet Tank Empty

Most people never think of this trick. The toilet tank is sweating because there is cold water in the tank. What if there was no water in the tank? One may be tempted to ask, “How am I going to flush a toilet without water?”

  • On the wall behind the toilet, there is a shut-off valve.
  • This valve controls the water flowing to the toilet.
  • To turn off the water flow to the toilet, turn this valve clockwise.
  • Flush the toilet to empty the tank.
  • The next time you come to use the toilet, open the valve by turning it counterclockwise to fill the tank. This will take seconds.
  • After the tank is full, turn off the shut-off valve.
  • Do your business and flush the toilet.
  • This will leave the toilet tank empty until the next use, when you will follow the same steps.

Doing this means the toilet tank will only hold water for 1 or 2 minutes which is not enough for condensation to occur. Although a small amount of water will still be left at the bottom of the tank, most water will be removed.

When you flush the toilet, hold the flushing handle down longer to remove as much water as possible.

2. Take cooler and shorter showers.

This method does not appeal to most people. Unless you are straight out from jogging and have a meeting to catch, most people prefer spending more time in the shower with warm water caressing their bodies.

Asking them to take quick and cold showers is a hard proposition to sell. If you, however, went ahead and did it, it would minimize the humidity in your bathroom and therefore stop or lessen your toilet sweating.

3. Drying the Bathtub/Shower walls After Showers

Drying your bathtub and shower cubicles after a shower will reduce the amount of evaporation in the bathroom. When evaporation happens in the tab or the shower cubicle, the moisture ends up on the surface of the cold toilet tank, and therefore the toilet starts to sweat.

Cleaning the bathtub or shower cubicle with cold water after taking a shower will also lessen the rate of condensation. This method, on its own, will, however, have a minimal effect and will need to be combined with other methods like taking shorter and cold showers.

4. Use an Exhaust Fan While Taking Shower

If your bathroom has a fan, switching it on while showering and a few minutes after the shower will help in driving away the warm and humid air out. Cooler air will come in to replace the warm air which has been expelled.

Leaving your bathroom door ajar after taking a shower while the fan is still running will help in air circulation between the bathroom and the rest of the house.

You should also avoid flushing the toilet straight after taking a shower when the air in the bathroom is more humid.

5. Install Air Conditioning

Installing air conditioning is not cheap, and if you are doing it for the sole reason of stopping a sweating toilet, then it won’t be worth it. If you, however, feel that your entire house needs air conditioning, then, by all means, go for it.

A cheaper alternative is to buy a portable air dehumidifier that you can place in your bathroom. With the dehumidifier, you will be able to bring down the temperature in your bathroom and therefore control a sweating toilet.

6. Use a Toilet Drip Tray

A toilet drip tray will not stop a sweating toilet, but it will collect the water to prevent the rotting of your bathroom floor or subfloor. It is not a pretty thing, and most people will not want it in their bathrooms.

Instead of a toilet drip tray, you can consider laying down decorative rags around the base of your toilet. They absorb the water and will look way better than a tray.

7. Close Your Bathroom Windows on Hot Days

You will definitely want to close your bathroom windows on hot days. Although you might not have fresh air in the bathroom, you will lessen the toilet sweat.

Hot air will therefore flow from the outside of the house to the cold body of a toilet tank which will increase the rate of condensation.

Permanent Ways of Fixing a Sweating Toilet

These methods will completely or almost completely fix a sweating toilet. Some are a bit more expensive.

1. Insulate the Toilet Tank

Insulating a toilet tank is one of the best and most inexpensive ways of fixing a sweating toilet. It will sort out the issue for you, and you can do it on your own.

Insulation makes it harder for heat to flow between the inside of the toilet tank and its surroundings. A toilet tank insulation kit can be found in any home improvement store. It contains the insulating foam, adhesive, and adhesive applicator. You will also need a pair of scissors, a scrubbing brush, spray-based cleaner, and a hair dryer or a 100W bulb.

How to Insulate a Toilet Tank

  • Turn off the water supply to the toilet. You will find the shut-off valve on the wall behind the toilet. Turn the valve clockwise.
  • Flush the toilet.
  • Remove the toilet tank lid and place it in a safe place where it cannot break.
  • Spray the cleaner all around the inside of the toilet tank, focusing more on the walls.
  • Scrub your toilet walls thoroughly with the brush, using the little water at the bottom of the tank to rinse it.
  • Soak up the water at the bottom of the toilet with the sponge, and now scrub the bottom of the tank to remove all the stains.
  • When the tank is clean, use a dry towel or sponge to dry the toilet tank, including all the parts as much as you can.
  • Bring in the hair dryer and blow into the tank until it is completely dry.
  • If you don’t have a dry, connect a 100 watts bulb to the top of the tank and leave it for 12 hours to completely dry the tank.
  • Cut the insulation from sheets according to your toilet tank size. Apply the adhesive and start sticking it into your toilet tank’s walls. Gently press on each sheet to help it attach properly.
  • It will be challenging to stick the foams at the bottom of the tank due to the many parts, but with patience, you will do it.
  • Wait for 12 hours before opening the water to the toilet. This will give the sheets enough time to set and dry completely.

Insulating a toilet tank is both economical and will bring a long-lasting difference to a sweating toilet.

2. Install an Anti-Sweat Valve.

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  • Eliminates condensation, prevents dripping of toilet tanks, ends moisture on floors
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An anti-sweat valve preheats the water flowing to your toilet tank, therefore, preventing the toilet from sweating. It is installed behind your toilet and connected to the water supply line.

While an anti-sweat valve is not expensive, a plumber will charge you 100 to 300 dollars to install it. If you can do it on your one, then it might be worth the investment.

If you suspect that installing an anti-sweat valve will involve interfering with your bathroom wall, it will be more expensive, and you are better of replacing your toilet with an insulated toilet.

3. Install an Insulated Toilet

Replacing your sweating toilet with an insulated toilet will take care of the problem forever. These types of toilets are made for areas which are badly affected by this problem.

If you have a two-piece toilet, you will actually not need to replace the bowl. Just see if you can find an insulated toilet tank that is compatible with the bowl.

The toilet tank model number is normally stamped inside the toilet tank. Write it down and see if the toilet manufacturer has a similar model that is insulated.

If you get it, then this is how to install a toilet tank.

If you have a one-piece toilet, you will need to replace the entire toilet. There are many toilets that are sold with an insulated tank.

Insulated Toilet

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4. Install a Tankless Toilet.

Kohler veil

Tankless toilets are the toilets of the future. If you are looking to completely do away with toilet sweating in your bathroom, then I suggest you install a tankless toilet.

A tankless toilet has no toilet tank and, in its place, receives water under high pressure, which is sufficient to flush the toilet. These are the toilets you normally see in public toilets, although in private homes, tankless toilets look nicer.

Most tankless Toilets are also smart toilets and are, therefore, more expensive than tank toilets. They are also dependent on electricity for the small pump to work, so if you live in an area with frequent power outages, you might not like this option.

An alternative to tankless toilets is wall-hung/wall-mounted toilets. In this case, the toilet tank is concealed by the bathroom wall, while the bowl will be mounted on the wall. Installing a wall-hung toilet is expensive, but they will permanently sort you out, and they also look so stylish.