Toilet Flange Sits ½ Inches Above Floor? 4 Ways To Fix It

One of the main things to get right when installing a new toilet is the height of the toilet flange. The toilet flange is a metal or PVC ring that goes into the toilet drain and prevents the toilet from leaking during use. In addition to this primary function, the flange also elevates the toilet bowl so that it sits flush with the bathroom floor. However, if the toilet flange is too high, the toilet will feel wobbly, and it could leak.

A toilet flange installed at ½-inch above the floor is too high and could cause problems. You could fix the issue by raising the floor, adding thickness under the toilet, or installing a toilet with a mold deep enough to accommodate the extra height. Alternatively, you can remove the flange and shorten the pipe for a lower flange installation.

What’s The Maximum Height Of Toilet Flange Above the Floor?

The maximum height of a toilet flange above the floor should be ¼ inches. Nearly all flanges available on the market have a height of ¼ inches and are designed to go on top of your finished floor. However, there are instances when your contractor may install the flange on the subfloor.

This could happen if you buy a new house and the floors are not yet installed or if you’re remodeling your home and the plumber finishes work before you install the floors.

A flange installed on the subfloor is too low; thus, you have to use spacers to raise it. These spacers generally have ¼ or ½ inches in height. However, there are situations when the spacer raises the flange too much, and you’ll find that it sits ½ inches above the floor.

In other cases, the culprit could be the drain pipe that raises above floor level. In all these cases, you’ll have to find solutions to prevent the toilet from wobbling and leaking when you use it.

How To Fix A Flange Sitting ½ Inches Above Floor

If the toilet flange is ½ inches above the floor, you’ll find that it will prevent your toilet from sitting flush with the floor. The result is a toilet that moves from side to side, and that could leak when using it. Luckily, there are various ways to solve the problem. Check them out below.

Check The Toilet Mold

The first thing to check is the toilet mold; more precisely, the toilet base mold and see if it is high enough to accommodate the ½-inch flange height.

Although all toilet flanges should sit ¼ inches above the floor, some vintage toilet styles have a base that is high enough to fit a higher flange under it. Measure the distance between the base edges that rest on the floor and the toilet’s drain opening to check the mold height.

Raise The Floor

If your toilet has a standard mold and no way to fit a ½-inch flange under it, a solution could be to raise the floor.

There are several ways to do this, such as installing a new floor on top of the existing floor – although this would be expensive and time-consuming.

Alternatively, you could make a plywood base for the toilet. This is the simplest and cheapest way to raise the floor under the toilet without affecting the rest of your bathroom floor.

To do this, place your toilet on a sheet of ¼-inch plywood and draw the shape of the toilet base with a pencil. Remove the toilet and cut the plywood base with a hacksaw.

Now, fix the plywood to the toilet base with duct tape and smear some removable paint on the flange. Position the toilet over the flange so that you can mark the position of the flange opening on the plywood sheet.

Cut out the opening. Sand all edges and seal the plywood with a waterproof coating or a waterproofing membrane. Glue the plywood to the toilet and install it over the flange.

Add Something To Rest The Toilet On

Adding plywood under the toilet provides you with a solution that needs little to no maintenance. If you don’t feel like cutting plywood, though, you can fill the gap with grout to fix the problem.

What You’ll Need

  • Grout
  • Water
  • Rubber shims
  • Putty knife
  • Rubber gloves
  • Bucket
  • Level

1. Mix the grout 

In a bucket, mix the grout powder and water to form a paste, following the instructions on the package (or mixing a 6:1 grout to water ratio).

2. Set the toilet in place 

Place the toilet over the flange in the correct position for installation. Insert a few rubber shims under the base to hold it at an even level with the flange. Check the level and make sure the toilet base is parallel with the floor on all sides.

Using rubber shims during this step is crucial. Unlike plastic, rubber adheres to the porcelain and prevents the toilet from moving as you apply the grout.

3. Fill the gap with grout

Fill the gap between the floor and toilet with the grout you mixed earlier. A putty knife can help you push the grout in the gap. Let it dry and cure for at least 24 hours.

4. Remove the shims and add more grout

Once the first grout layer is cured, pull out the shims from under the toilet. Mix new grout and fill the gaps the shims left behind. Let it dry and cure for another 24 hours.

5. Fix the toilet

You can now complete the toilet installation by tightening its nuts. Check the balance and apply a layer of silicone caulk around the toilet base for added stability.

Remove The Flange And Shorten The Pipe

Sometimes, you may find that the flange is installed correctly, but the drain pipe raises above the floor level. An easy way to fix this is by removing the flange and cutting the pipe flush with the floor.

What You’ll Need

  • Hacksaw
  • Flathead screwdriver
  • New flange
  • Dremel cutting tool
  • Mallet
  • Rubber mallet
  • Toilet flange screws
  • Drill
  • Drill bits
  • Rubber gloves
  • Goggles
  • Respirator
  • Ruler
  • Marker

1. Prepare for the task

To cut the drainpipe, you will have to remove the toilet first and plug the drain with a cloth or toilet paper.

Put on the protective equipment and shut off the water supply to the toilet. Flush two or three times to drain all water from the tank and bowl. Unscrew the nuts holding the toilet in place and remove the toilet bowl from over the flange.

If the toilet is fixed with caulk, remove all silicone caulking to make it easier to remove.

2. Remove the old flange 

The easiest way to remove the old flange is by cutting out a section with a hacksaw, then pulling out the rest of the flange from the drain. If the flange is stuck, you can use a flathead screwdriver and mallet to dislodge it from the drain, paying attention not to damage the pipe.

3. Measure and mark the cut line 

While you’re supposed to install the toilet flange above the toilet, the drain line must be flush with the subfloor. Measure the cut point with a ruler and mark it on the pipe before beginning.

4. Cut the pipe 

Cut the drainpipe with a Dremel tool (or a similar cutting tool), paying attention not to cut too low or damage it in any way.

5. Install the new flange

Once the drain line is cut flush with the subfloor, you can install the new toilet flange. Make sure to buy the right flange size and push it into the drain. The rubber seal around the flange should fit tightly inside the drain line, so that you should use a rubber mallet to push it in place.

If the flange slides into the drain without effort, it is either too small, or you have to adjust the seal.

Once the flange is positioned correctly, you can drill screw holes into the floor and fix the flange with screws. At this stage, remove the cloth from the drain (if it’s toilet paper, you can simply flush it after the toilet is installed) and install the toilet.

Seal the edge around the toilet with silicone caulk for added stability, and let it dry for a few hours before filling the toilet with water and using it.

Final Thoughts

A toilet flange that sits ½ inches above the floor could be a cause for concern, but the issue is relatively easy to fix. Whether you decide to fill the gap, cut the drain line, or even install a new floor, we hope this guide has helped you find the right solution for you.

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