How To Fix a Leaking Toilet (2024)

Step 1

Turn off the water supply

• Typically, there’s a water shut off valve near the base of the toilet.
• Turn the control handle to the right to shut off the water supply.
  • Some valves need to be turned repeatedly, while others only take a quarter turn.
• If there’s no shut off near the toilet or if the shut off won’t close completely, turn off the main water supply.

Dan Stout for Family Handyman

Step 2

Drain water from the toilet

• Flush the toilet and hold the handle down to drain out as much water as possible.
  • Because the water supply is off, it will drain without refilling the tank.
  • This will remove most of the water, but not all.
• Use a wet/dry vacuum or a sponge to remove the last of the water.
  • While the water in the tank is clean, the water in the bowl and trap definitely isn’t. Wash your hands as needed.
• Disconnect the water supply line from the toilet tank.
  • Have paper towels or rags on hand for any water that leaks out the fill valve.

Dan Stout for Family Handyman

Step 3

Pull the toilet

• Remove the toilet seatand set it aside.
• Remove the bolt caps, then the nuts that secure the toilet to the floor.
  • If the bolt spins along with the nut, grab the exposed bolt above the nut with locking pliers.
  • Loosen the nut just enough to squeeze in a hacksaw blade below the nut and saw through the bolt.
• Lift the toilet high enough to clear the bolts (about three or four inches) and set it aside.
  • Lift with your legs rather than your back.
  • If the toilet is too heavy, disconnect the tank from the base and remove each half separately.
• Stuff a rag into the drain line to keep sewer gases contained.
  • Use a rag that’s about the size of a small hand towel. You do not want the rag to fall into the waste pipe. (Trust me on this one.)
  • Note: Some of the photo details were obscured with the rag in place, so for the sake of clarity I removed the rag blocking the toilet hole. Keep the rag in place on your own project,

Dan Stout for Family Handyman

Step 4

Scrape wax from flange and toilet

• Scrape all the old wax from the bottom of the toilet and toilet flange with a putty knife.
• If the toilet was caulked to the floor, scrape off any stuck-on caulk.

Dan Stout for Family Handyman

Step 5

Identify the cause of the leak

This step will be unique to your situation. Sometimes the issue is immediately apparent. Other times, it takes more investigation.

In the toilet I was repairing, it turned out that whoever installed the bathroom flooring hadn’t leveled the floor around the toilet flange. Rather than take time to fix their mistake, they’d simply left a handful of tile spaces and hoped things would be OK. This poor fix allowed the toilet to rock, which over time pushed the wax seal out of alignment and caused a leak.

Here are some common causes of leaks around the flange:

• Broken flange.
  • Identified by a crack in the flange, usually on the outside of the slot that holds the toilet bolt.
  • Most common with cast iron or plastic flanges.
  • Repair with a flange reinforcement ring.
• A flange that’s too low.
  • Flanges that sit more than 1/4-inch below the finished floor can have this problem.
  • Common when a non-plumber installs a new floor, and doesn’t understand the importance of a good seal at the flange.
  • Repair with a flange extender.
• Wax ring failure.
  • A wax ring won’t deteriorate, but it can be pushed down, squeezed to one side or twisted out of place by a loose, wobbling toilet.
  • If nothing appears to be wrong, resetting the toilet with a new wax ring might be the only thing you need to do.
  • This is the most common problem when toilets leak at the base. Luckily, it’s also the easiest solution.

Dan Stout for Family Handyman

Step 6

Repair the issue

Once you’ve identified the root issue, it’s time to fix it.

• Repair broken flanges with a flange reinforcement ring.
• Repair low flanges with a flange extender.
• Repair damaged wax rings by replacing the ring and stabilizing the toilet to prevent repeat issues.
  • In my case, I added another vinyl tile to level the flooring beneath the toilet.
• If the flooring is still wet from the leak, clean it up and dry it thoroughly.
  • Leave a fan on it to speed this process.
• If the leak has gone on for a long time, the flooring or subfloor may be damaged. Remove any rotten or weakened material and replace it.
  • If the subfloor or joists are rotten, this will take some carpentry skills. If you’re not comfortable with that type of work, it’s best to bring in a pro.

Dan Stout for Family Handyman

Step 7

Install the new wax ring

• Place the toilet bolts in the flange.
  • The wide bottom of the bolt fits in the wide opening of the flange, then slides into place.
  • Note that these new bolts are taller than the ones you removed. This is to make installation easier. You’ll trim them down to size after setting the toilet.
• If the bolts came with plastic washers, slip them over the bolts so they fit snugly against the top of the flange.
  • These will keep the bolts upright and in place while you set the toilet.
  • If you haven’t already removed the rag, be sure to do so now.
• Set the wax ring in place.
  • If you have a “reinforced” wax ring with a plastic spout, it’s usually easiest to set it onto the flange opening.
  • If you have a plain wax ring, it’s usually easiest to set it around the spout on the bottom of the toilet.
  • I recommend the reinforced rings. They’re an extra layer of protection for only a few dollars more.

Dan Stout for Family Handyman

Step 8

Set the toilet

• Lift the toilet high enough to clear the bolts.
  • Remember, the new bolts are taller than the ones you removed.
• Set the toilet down as straight as possible. You want to avoid knocking the wax ring out of center.
  • You may not get it perfectly straight and even. That’s fine, as long as you don’t damage the wax seal.
• Rock the toilet back and forth gently, pushing the wax tight.
  • Don’t twist the toilet into place, which can create a void in the wax seal.
• Put the washers and nuts on the toilet bolts.
  • Hand-tighten both sides, then switch to pliers or a wrench.
• Alternate from one side to the other so the toilet is tightened with uniform pressure.
• Tighten each side slightly, then rock the toilet. If it’s loose, continue tightening until it sits tight and even against the floor.
• Do not over-tighten. Tightening too much can crack the porcelain.
• Snap off the top of the bolts to bring them down to the right height.
• Use pliers for this, or a hacksaw to cut through and pliers to finish the job.
• Replace the toilet bolt caps.
• Replace the toilet seat.

Dan Stout for Family Handyman

Step 9

Reconnect water supply

• Connect the water supply to the fill valve on the toilet tank.
• Hand-tighten the supply line.
  • You should not need pliers to tighten the supply line. If you do, there is a good chance you will strip the plastic threads.

Dan Stout for Family Handyman

Step 10

Test and adjust as needed

• Flush the toilet and allow it to fill up. Look for leaks around the water supply, tank and base.
• Sit on the toilet a few times and move from side to side. If it rocks or shifts, tighten the bolts further or put a shim in place.
• Once the toilet is definitely tight, stable and running without leaks, caulk the gap between the toilet and floor.
  • How much needs to be caulked depends on the code requirements where you live. Some areas require caulk all around the toilet. Others allow a gap in the back, while a few do not require caulk at all.

Dan Stout for Family Handyman