How to Repair a Toilet Bowl Flange Seal

If you smell an unusual odor in your bathroom or see water seeping out from underneath your toilet, you most likely have a bad flange seal. The flange (also called the "closet flange" or "toilet flange") is a metal ring that connects your toilet bowl to your home's sewer system. A wax ring, or seal, sits between these two pieces, sealing the toilet connection water and air tight. Over time, these seals can disintegrate. The procedure for how to repair a toilet bowl flange seal is fairly straightforward and can be done by the DIYer.

• 1

  Turn off the water supply for the toilet where you want to repair the flange seal. Look behind the toilet to locate the water supply shut-off valve. These are typically mounted on the wall underneath the tank. Turn the knob on the end of the valve clockwise to shut off the water.

• 2

  Flush the toilet to remove all the water in the tank. Continue pressing on the handle and allow all the water inside to escape. Lift the lid off the tank. Wipe up any remaining water with the sponge.

• 3

  Unscrew the water supply hose from the underside of the tank. Use the adjustable wrench to remove the tank bolts on the bottom of the tank. Lift the tank off the back of the toilet.

• 4

  Insert the edge of a flat bladed screwdriver underneath the plastic caps on the sides of the toilet bowl and pop them off. Unscrew the flange bolts with the wrench. Run the utility knife along the caulk at the base of the toilet. Gently pull the toilet bowl off the floor. Lift it up and move aside.

• 5

  Use the putty knife to scrape away any old remnants from the wax ring. Clean up any stubborn pieces with the isopropyl alcohol and rag. Insert new flange bolts into the flange. Secure with the plastic washers. Press the new wax ring into place around the flange.

• 6

  Turn the toilet bowl over upside down. Some water may run out, this is normal. Clean off the underside of the toilet of any old wax with the alcohol and putty knife as you did around the flange opening.

• 7

  Turn the toilet bowl right side up. Slowly lower the bowl over the flange. As you do so, align the flange bolts with the holes in the base of the toilet. The outlet in the bottom of the toilet should line up with the flange opening as well. Once the toilet bowl is in position, press down to seal.

• 8

  Insert the plastic and rubber washers over the flange bolts. Thread the flange nuts into place. Tighten with the wrench, slowly, one side of the bowl at a time, until the bowl is secure.

• 9

  Place the tank on the back of the bowl, ensuring that the cone gasket in the bottom of the tank lines up with the inlet on the back of the bowl. Insert the tank bolts into the bottom of the tank. Secure with the tank nuts from the bottom.

• 10

  Wrap the inlet on the underside with plumber's tape. Connect the supply hose coupling. Turn the water supply on by rotating the knob at the end of the valve counterclockwise. Allow the tank to fill.

• 11

  Flush the tank. Check for leaks. Tighten any nuts or couplings, if necessary. Replace the tank lid.

• 12

  Saw off the flange bolts above the nut with the hacksaw. Press the plastic caps into place over the bolts. Insert the silicone caulk into the caulk gun. Trim off the end at the 1/4 inch mark at a 45-degree angle. Caulk around the base of the toilet.