Why is the toilet sweating?

Question

Last night there was a puddle of water on the floor and tank of my toilet looked like it ran 10 miles, sweat all over it! What do I need to do to take care of this annoying problem?

Answer 1

Simplest way is to get a tank cover. They also make insulation kits that go inside the tank. Most expensive is the tempering valve that adds warm water to the cold that fills the tank. If you have a way of circulating air in the room, this will also help.

Answer 2

The same as a glass of ice water setting on the table.  The cold water inside is colder than the outside.  If you live in a high hummed place then the water will condense onto the cold surface.....The toilet tank.

   I'm glad I moved from the high hummed area of the US.  I now live in Idaho.

Answer 3

The toilet tank is sweating because the air around it is much warmer than the cold water inside the tank. The hotter humid air causes it to sweat like a glass of ice tea on a hot humid day.

If you have an AC turn it on, cooling the air inside the room might take care of it.

There are also toilet tank insulators that go inside the tank available at most home improvement stores that will work if the AC is not enough.

One more thing , when your toilet is used it should fill with water and than turn off completely. If it runs even a small amount that means that fresh cold water is being added to the tank and makes the toilet tank water colder than it otherwise would be and sweat. If the water was allowed to slowly warm to room temp as most toilet do this would not happen. If it does run the leaking valve or flapper needs to be replaced and that should correct the problem.

Answer 4

Turn the exhaust fan on and run it for at least 10 minutes after you finish your shower. This should lower the humidity in the bathroom.  If you are lacking a fan, open a window and get a fan in the window.  Verify that it is condensation and not a leak in the tank.