How to Install a Toilet Flange Extender


Installing a toilet flange extender is an important part of fixing a loose or damaged toilet. The flange is the piece at the base of the toilet that connects to the drain pipe, and an extender raises the flange to the proper height when it has become sunk into the floor over time. Replacing or extending the flange ensures a solid, leak-free connection between the toilet and the drain pipe.

While this is not an extremely difficult job, it does require some plumbing knowledge and skill. Having the right instructions, tools and materials on hand will ensure the extender can be installed properly. This guide will walk through the entire process step-by-step to provide DIYers with everything they need to know to complete this project with success.

What is a Toilet Flange?

The toilet flange, also known as a toilet horn, is a pipe fitting that sits between the bottom of the toilet and the drain pipe in the floor. It has bolt slots that hold the bolts and washers used to secure the toilet in place on the floor. Here are some key things to know about toilet flanges:

  • They are usually made of PVC, brass or stainless steel.
  • The flange has a hub that fits into the top of the drain pipe.
  • When installed properly, the flange should be flush with the finished floor.
  • It must provide a secure seal between the toilet and drain pipe.

The flange has a very important role. It stabilizes the toilet and prevents any wobbling or rocking when weight is applied. It also creates a tight connection to the drain pipe below, ensuring waste materials do not leak out.

Over time, the flange can become loosened or detached from the floor, causing the toilet to wiggle and leak. An extender can be installed on top of the existing flange to bring it back up to floor level for a renewed seal.

When Do You Need a Toilet Flange Extender?

There are a few situations when a toilet flange extender may be required:

  • Tile floor has been installed or replaced – The thickness of the new tile raises the surface level of the floor up. This leaves the existing toilet flange too far below the floor surface. An extender is needed to bring the flange back up to the proper height.
  • Rotting or deterioration of subfloor – If the subfloor around the toilet has sagged, rotted or deteriorated over time, this can cause the flange to sink. Adding an extender ring corrects the flange height.
  • Flange is broken – In some cases, the toilet flange can become cracked, rusted or broken. Replacing the flange may be needed. Adding an extender is an alternative to replacing the entire flange.
  • Leaking between toilet and drain – If water is leaking between the base of the toilet and the drain pipe, an extender can help provide a tighter seal and prevent leaks. This is often an indication the flange has sunk beneath the floor level.
  • Toilet rocks or wobbles – If the toilet is moving, rocking or wobbling when sat upon, the flange may no longer be providing a stable connection. An extender can stabilize the toilet and eliminate rocking.

Adding a toilet flange extender restores the flange to the proper height to create a solid connection for an attached toilet.

How to Install a Toilet Flange Extender

Installing a toilet flange extender involves careful removal of the toilet, checking the existing flange, attaching the extender, re-securing the toilet and checking for leaks or wobbles. Here are the step-by-step instructions:

Materials and Tools Needed

To install a toilet flange extender, you will need:

  • Toilet flange extender kit
  • Caulk and caulk gun
  • Screwdriver
  • Bolts to match extender kit
  • Wax ring
  • Putty knife
  • Shop vacuum
  • Gloves
  • Safety glasses

Step 1: Turn Off Water Supply and Empty Toilet Tank

The first step is to turn off the water supply valve behind the toilet. This is the valve that feeds water to the toilet tank. Turning it clockwise fully will shut off the water.

Next, flush the toilet to empty the tank. Use a sponge to remove any remaining water in the bottom of the tank or bowl.

Step 2: Disconnect and Remove Toilet

With the tank empty, the next step is to disconnect the toilet from the floor flange . Use a screwdriver to remove the bolts holding the base to the flange. Carefully rock the bowl loose and lift it off the flange.

Set the tank and bowl aside separately. Place towels around the exposed flange to soak up any remaining water.

Step 3: Remove Old Wax Ring

With the toilet removed, you will see the circular flange still attached to the floor. Use a putty knife to carefully scrape off the old wax ring seal. Try to remove all remnants of the wax. Dispose of the old ring.

Also use the putty knife to lightly scrape the bottom of the toilet where the wax was attached. Remove all old wax and debris.

Step 4: Check Flange Height

Check that the top surface of the flange is about 1/4 inch above the floor. If it is lower than the floor level, the extender will raise it back up to the proper height.

While checking the height, also inspect the flange for any cracks, rust or damage. Make sure the hub is still firmly attached to the drain pipe.

Step 5: Apply Caulk to Flange and Hub

Squeeze caulk around the base of the toilet flange where it will make contact with the extender. Also apply caulk into the hub where it fits into the drain pipe.

This seals any gaps between the flange and floor or pipe below. Smooth the caulk with a finger to evenly distribute it.

Step 6: Attach Flange Extender

Follow the directions that come with the extender kit. Most utilize a split extender ring that slides under the flange. Apply additional caulk underneath if needed.

Push the extender ring down firmly so it is fully seated under the existing flange. The extender should now raise the flange up to floor level.

Install the provided extender bolts into the bolt slots on the extender ring.

Step 7: Replace Wax Ring

With the extender secured in place, install a new wax ring seal on the bottom of the toilet where it will make contact with the raised flange. Press it evenly into place around the toilet horn.

Some options are a standard wax ring or a wax ring with a plastic funnel guide. The guide helps center the toilet on the flange when setting it down.

Step 8: Reinstall Toilet

Carefully lift up and position the toilet centered above the flange extender. Line up the mounting holes with the extender bolts.

Tip: Have a helper hold the toilet in place if needed while installing.

Gently lower the toilet straight down onto the wax ring without shifting its position. Rock it slightly side-to-side to fully imprint the wax ring and create a seal.

Reinstall the washers and nuts onto the extender bolts and tighten evenly until snug. Do not overtighten.

Step 9: Reconnect Water Supply

With the toilet secured in place, reconnect the water supply line. Make sure all fittings are tight.

Turn the shutoff valve counterclockwise to turn the water back on. Check for any leaks.

Refill the tank and flush to test out the toilet. Check around the base for any leaks or water seeping out. If leaks are present, tighten the bolts further or reset the toilet onto the flange.

Step 10: Seal Base with Caulk

Once you’ve confirmed there are no leaks, apply a bead of caulk around the entire base of the toilet along the floor. This provides an additional barrier against moisture on the floor.

Wipe away any excess caulk with a damp cloth. Allow the caulk to fully cure for several hours.

Tips for Installing a Toilet Flange Extender

  • Carefully follow the manufacturer’s instructions included with the extender kit.
  • Wear protective eyewear and gloves when removing toilet and flange.
  • Disconnect the water supply before attempting to remove toilet.
  • Check that the floor flange is level and securely attached before installing extender.
  • Apply caulk generously underneath the extender and on top of the hub.
  • Press extender firmly in place before reinstalling toilet.
  • Do not overtighten bolts or damage may occur. Tighten just until snug.
  • Replace wax ring each time you reinstall toilet to maximize the seal.
  • Check for stability and leaks after installing – readjust if needed.

Common Questions about Toilet Flange Extenders

How do I know if I need a toilet flange extender?

If the existing flange is sunk into the floor, sits lower than the floor level, or the toilet rocks and wobbles, adding an extender can help stabilize and seal the toilet base. Leaks around the base or under the toilet are also a sign help is needed.

Can I use two wax rings instead of an extender?

It is not recommended to use two stacked wax rings to raise the toilet height, as this makes the toilet unstable and prone to shifting and leaking. Flange extenders are the proper permanent solution.

How much does it cost to replace a toilet flange?

The average cost to have a plumber replace the entire toilet flange with a new one is $150-$300. DIY flange extender kits can cost $10-$30 for the parts.

Can I use shims under the toilet instead?

Shims are meant to provide temporary stability. They do not provide a long-term solution like a flange extender and wax ring do. Shims can actually crack and damage the toilet base if too much weight is on them.

How do I disconnect the toilet from the flange?

Turn off water supply, empty the tank and bowl. Remove mounting nuts and bolts. Gently rock the bowl side-to-side while lifting up to fully detach from the flange. Avoid hitting the bowl on the floor.


Installing a toilet flange extender is an important repair to stop rocking, leaking and potential damage around the toilet base. With the right tools and proper instructions, this is a DIY project a homeowner can successfully tackle in order to stabilize and re-seal the toilet. Always turn off the water supply and empty all water from the tank and bowl before removal. New wax rings and caulk then ensure a tight seal when resetting the toilet on the raised flange extender. Feel free to contact a professional plumber for assistance if any issues occur during the extender installation process.