Home>Discussions>TV>Ask This Old House>condensation at the toilet
3 posts / 0 new
Last post
condensation at the toilet

Hi, to get rid of the coldwater condensation that seems to be rotting the floor now under the toilet, will replacing the cold water line with a hot water line fix this problem?
Thank you for any advice

Re: condensation at the toilet

You can get a mixer valve to install between the hot & cold lines to provide warmer water to the toilet tank. Richard did this on an Ask This Old House episode a while back to solve your exact problem.

Re: condensation at the toilet

Condensation on the outside of a toilet tank is the result of warmer humid air in the room coming in contact with the cold tank …… just like a glass filled with a cold drink. Condensation on a toilet tank is most often a problem in the summer in humid climates; but can also be a problem in winter. Houses on well water can suffer a great deal from this problem.

Is the toilet leaking?

A constant exchange of fresh cold water in the tank will cause condensation to form on the outside of the tank when the humidity is high in the bathroom. Check the toilet for leaks with the flapper or overflow tube.

Is there enough ventilation in the bathroom? You may need to install an exhaust fan.

The majority of toilets installed around here for the 18 years or so have insulated tanks.
With a styrofoam cup there isn’t any issue with condensation unlike the example with a glass.

Toilet tank liner kits are available to insulate the tank, check your local hardware store or home center.

You will still get condensation on the metal intake tube. If you replace the metal tube with a plastic intake tube you eliminate that problem too, Plastic usually doesn't sweat because it is a better insulator than metal tubes.

There are tempering valves available that supposedly allow a little bit of water from the hot water supply line to trickle into the cold line. Someone I know tried this, it didn't work, because the hot water line was usually not hot when you first flushed the toilet. By the time the hot water got up to the area of the toilet, the toilet was finished flushing.

Besides …. thinking about wasting some hot water for the toilet is literally flushing money down the toilet….. whereas the liner doesn’t cost a dime after it’s installed.

Just a thought.:)

Sponsored Stories

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.