The sound of a running toilet is perhaps one of the most annoying noises you'll hear in a home. Not only will it keep you up at night, it means that -- drip by drip -- money is going down the drain in the form of wasted water. Fortunately, sealing a toilet valve flapper is one of the quickest and least-expensive home repairs you'll ever face. If you have silicon grease around the house, you won't even need to make a trip to the hardware store. And even if you do, silicone grease is inexpensive. Best of all, using silicone grease means you don't have to disassemble any part of your toilet.
Turn off the water to the toilet at the shutoff valve behind the toilet.
Flush the toilet to empty the tank. Remove the tank cover. The tank cover is a lid that sits on top of the tank.
Absorb any water remaining in the bottom of the tank, using towels. There should only be an inch or two of water.
Find the flapper. It will be at the end of a chain. The flapper lifts up to empty the tank into the toilet bowl when you flush it, then lowers to seal the water in the tank so it can refill.
Pull the flapper upward and clean it, using dish detergent and a scrubber. Rinse off the detergent. Dry the flapper and the rim it sits on at the bottom of the tank.
Apply a thin layer of silicone grease all the way around the bottom ridge of the flapper, using your fingertip.
Lower the flapper and replace the tank lid.
Turn the water back on at the shutoff valve.