How to Fix a Toilet Seal

Co-authored by Dave Jones

A pool of water forming beneath the toilet generally means that the wax seal between the toilet and the flange has failed. Repairing a toilet seal requires you to unbolt the toilet from the floor, replace the seal and then put the toilet back in its original position.

Part 1

Part 1 of 2:

Remove the Toilet

Removing the toilet means loosening the bolts that connect it to the flange on the floor. You will need to either spread out a blanket or piece of cardboard to place your toilet on or to place the toilet in the bathtub after you remove it.

1
Turn off the water supply to the toilet by turning the valve in a clockwise direction. The water supply valve will either be located behind the toilet or in the crawl space or basement space directly beneath the toilet.^{[1]
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2
Remove the lid of the toilet tank and put it in a safe place out of your working area. It might be good to put the lid in a nearby closet or other out-of-the way place, so that it would not get broken or tripped over.
- If the lid gets broken, you will most likely be buying a new toilet as finding a replacement toilet tank lid that fits properly is unlikely.
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3
Flush the toilet, holding down the handle so that as much water as possible drains from the tank and the bowl.^{[2]
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4
Use a plastic cup to scoop out any water that is left in the bowl and then dry up the last drops of moisture with a towel or dry sponge.
5
Disconnect the water supply line by turning the compression nut on the water supply line in a counterclockwise direction by hand.
- If you are unable to loosen the connection, use a wrench or a pair of pliers.
6
Pry the caps from the washers on the base of the toilet using a flathead screwdriver.
- Some covers just twist off, so try turning the caps counter-clockwise first.
7
Remove the nuts from the bolts at the toilet base using a wrench. Remove any washer as well. If the bolt spins as you turn the nut, then hold the bolt with a pair of pliers using your non-dominant hand.
8
Place the nuts, washers, and caps where you will be able to find them when the time comes to put the toilet back in place.
9
Hold the toilet under the bowl and rock it gently back and forth to break the old wax seal.^{[3]
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- The bottom of the toilet will likely have wax from the seal, so you should not set the toilet on anything cloth or anything that you wouldn't want to throw away.
10
Lift the toilet off of the floor and set it down on a piece of cardboard or in the bathtub.^{[4]
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Part 2

Part 2 of 2:

Replace the Seal and Reinstall the Toilet

Choose a new seal that has a surrounding core of soft urethane foam. This type of seal will do a better job of conforming to the toilet and to the flange to make a superior seal.

1
Scrape the wax seal off of the base of the toilet and off of the flange in the floor using a putty knife.
2
Take a new wax seal and place it on top of the flange, making sure that the seal is perfectly centered on the flange.^{[5]
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3
Lift the toilet and set it back on top of the flange, using the bolts as guides for placement. The toilet tank should be parallel to the wall behind it.
- You will probably need a second person to help you guide the base so that the bolts fit through the holes on the base of the toilet.
- Lower the toilet and then apply firm downward pressure on the bowl. The wax ring should mold to the base of the toilet to form a good seal and prevent sewer gases from escaping.
4
Put the washers over the bolts and thread the nuts onto the bolts. Tighten the nuts until the toilet is secure. Press down hard on the toilet and then tighten the nuts some more. Continue the process until the toilet is tightly secured to the flange, but do not over-tighten the nuts or you will crack the base of the bowl.^{[6]
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5
Reconnect the water supply by attaching the supply line to the water supply valve and turning the compression nut clockwise.
6
Turn the water supply valve on and flush the toilet several times. If you notice a leak beneath the base of the toilet, then seat the toilet more firmly toward the floor the floor by applying firm, even pressure on both sides of the rim of the toilet bowl, then tighten the nuts even more. Test again and, if you see no leaks, then your repair is complete.

Community Q&A

Question

Does the tank come apart from the rest of the toilet?

Donald Patriquin

Community Answer

Yes it does, but if it is an old toilet be prepared for further problems, as the gasket between the tank and the main part of the toilet may need to be replaced if it is old and cracked. Also, the bolts holding the tank to the toilet bowl may be rusted and require replacement. There is plenty of information on this out there (search "separating toilet tank from bowl"). If it ain't broke you likely don't need to fix it!
Question

What should I do if the screws are too long to place the cover that holds the toilet into the floor?

Community Answer

Cut them to the desired height with a metal handsaw after tightening the toilet down. Put caps on.
Question

I see water dripping from the water valve, but when I feel the valve, no water residue is detected. Where can this drip be coming from?

Community Answer

The first option could be a leak from the toilet fill valve base. The seal in the tank under the fill valve may be loose or worn. Hand-tightening the plastic nut under the tank for the fill valve may re-seal it. Otherwise, a new fill valve can be installed (with a new seal). It could also be a leaking source valve. Either tighten the seal nut on the valve shaft or back the valve all the way open to seal the valve shaft. The third option could be humidity condensation. Add an insulation cover to the toilet tank to prevent condensation. Some systems use a portion of hot water for the tank refill to warm it enough to prevent condensation, and in such setups the hot water valve portion could be opened more.

wikiHow Video: How to Fix a Toilet Seal

Things You'll Need

Wax replacement ring (neoprene , optional)
Towel or dry sponge
Plastic cup
Wrench or pliers
Flathead screwdriver
Piece of cardboard (optional)
New wax seal with urethane foam core
Putty knife (optional)
Rags or old towel
Mildew resistant silicone tub and tile caulk of appropriate color to match the bowl and flooring (optional)
Rubber gloves