The leaking toilet bowl:

There are several things that can cause a toilet bowl to leak. Here’s a list of symptoms and suggested repairs:

1. Water on the floor may be caused by condensation on the outside of the tank dripping onto the floor. If this is what is happening, you can cover the tank with a jacket made for this purpose. Another alternative is to line the tank with insulation. There are kits available to do this.
2. The water supply line to the tank may be leaking at the shut-off valve or at the bottom of the tank. If this is so, tighten the connection carefully with an adjustable wrench. Do not apply too much pressure to the wrench. If the water supply line needs to be replaced, use a flexible braided one, they don’t require sealing with Teflon tape, as the solid metal lines do. Once tightened, the seals on the flexible lines are virtually leak-proof.
3. If the flush tank is leaking where the tank joins the toilet bowl, try tightening the bolts that hold the tank to the bowl. Again, be careful not to over-tighten. If that doesn’t work, you will have to remove the tank and replace the rubber seal between the tank and the bowl. Shut off and drain all water before attempting this.
4. If the water is leaking from the base of the bowl, where it contacts the floor, you should try tightening the hold-down bolts first. The bolts are covered with porcelain caps that you carefully pry up and off with the tip of a flat screwdriver. Then tighten each bolt the same amount, or the same number of turns. If it still leaks, you will need to replace the wax toilet seal. This will require removing the toilet. The procedure for doing that was covered in the previous section.