How to Install a Toilet Flange Extender After Tiling
About This Project
This guide provides detailed instructions for installing a toilet flange extender, a necessary step when new flooring, such as tile, raises the floor height and leaves the existing toilet flange below the finished floor level. Installing an extender raises the mounting surface for the toilet, ensuring a secure, leak-proof seal with the wax ring.
Best for experienced DIYers and homeowners with some experience with basic plumbing knowledge and familiarity with power tools.
Tools & Materials
Adjustable Wrench
Bucket
HDX Multi-Purpose Sponge (2- Sponges) 32242
RSI 7.8 ft. x 12 ft. Blue 88% Shade Protection Knitted Privacy Cloth PF-812-BLUE
Work Gloves
Klein Tools 1/4 in. Cabinet-Tip Flat Head Screwdriver with 10 in. Heavy-Duty Round Shank 605-10
Adjustable Wrench
Fits various nut and bolt sizes with its adjustable jaw.
Bucket
Ideal for carrying or storing liquids.
HDX Multi-Purpose Sponge (2- Sponges) 32242
HDX Hydrophilic Sponge 7.25 in. x 5 in. x 1.875 in. (2-Pack) highly absorbent, the HDX Sponge washes, wipes, and rinses faster. Strong enough for use with acid based products like TSP. Heavy-duty polyester
RSI 7.8 ft. x 12 ft. Blue 88% Shade Protection Knitted Privacy Cloth PF-812-BLUE
The Riverstone line of privacy shade cloths is designed to offer easy to use, shade producing cloth that is UV stable and will last for several years in the hottest environments. All our knitted shade
Work Gloves
Protects hands during tasks.
Klein Tools 1/4 in. Cabinet-Tip Flat Head Screwdriver with 10 in. Heavy-Duty Round Shank 605-10
The Klein Tools 1/4-Inch (6 mm) Cabinet Tip Screwdriver 10-Inch (254 mm) with heavy-duty round-shank has a narrow cabinet tip that permits blade access where space is limited. It meets or exceeds applicable
Steps
Prepare Work Area and Remove Toilet
25 minsBegin by preparing the work area for the toilet removal. First, locate the shut-off valve on the wall behind the toilet and turn it clockwise to stop the water supply. Flush the toilet to empty the tank and bowl of most of their water. Use a sponge and bucket to remove any remaining water from the tank and bowl. Disconnect the water supply line from the bottom of the toilet tank using an adjustable wrench. Finally, remove the caps from the closet bolts at the base of the toilet, unscrew the nuts, and carefully lift the toilet off the flange. Set it aside on a drop cloth.
Clean and Prepare Existing Flange
15 minsWith the toilet removed, use a putty knife to scrape all of the old wax from the toilet flange. Be thorough and remove any debris, old bolt fragments, or residue from the flange and the surrounding floor. A clean surface is absolutely essential for the new extender to seal properly. Use rags, possibly with a degreaser or mineral spirits, to wipe the flange completely clean.
Measure Gap and Select Extender
5 minsPlace a straight edge or level across the drain opening, resting on the finished tile floor. Use a tape measure to measure the distance from the top of the old flange to the bottom of the straight edge. This measurement determines the required thickness of your flange extender. Extender kits come in various sizes (e.g., 1/4", 1/2", 3/4") and some are stackable. Choose the kit that brings the flange height to be flush with or slightly above the finished floor.
Apply Sealant and Position Extender
10 minsTake the flange extender and dry fit it on top of the old flange to confirm alignment. The closet bolt slots on the extender should line up with the slots on the original flange. Once confirmed, apply a continuous, generous bead of 100% silicone sealant around the entire top surface of the old flange. Carefully place the flange extender onto the sealant, pressing down firmly to create a good seal. Ensure the bolt slots remain aligned.
Secure the Flange Extender
10 minsSecure the flange extender to the subfloor. Your extender kit should include several long, corrosion-resistant screws. Using a drill or screwdriver, drive these screws through the designated holes in the extender ring, through the original flange, and firmly into the wood subfloor below. This step is critical for ensuring the entire flange assembly is solid and does not move, which prevents the toilet from rocking in the future.
Install Closet Bolts and Wax Ring
5 minsSlide the new closet bolts into the slots on the newly installed flange extender, with the threaded ends pointing up. Position them parallel to the back wall. Next, take the new wax ring and place it on top of the flange extender, centered over the drain opening. Press down gently to create a slight tack, holding it in place. Alternatively, some plumbers prefer to install the wax ring onto the outlet horn on the bottom of the toilet itself.
Set and Secure the Toilet
15 minsCarefully lift the toilet, keeping it level, and position it over the flange. Align the holes in the toilet's base with the closet bolts sticking up from the flange. Lower the toilet straight down onto the wax ring. Press down firmly on the toilet bowl with your body weight, and give it a slight side-to-side twist to compress the wax ring and create a solid seal. Place the plastic washers and then the metal washers and nuts onto the closet bolts. Tighten the nuts alternately, a little at a time on each side, until they are snug. Use a level to ensure the bowl is even. Do not overtighten.
Reconnect Water and Test for Leaks
15 minsWith the toilet secured, reattach the water supply line to the fill valve on the bottom of the toilet tank. Hand-tighten the connector, then give it a slight turn with an adjustable wrench. Be careful not to overtighten the plastic fitting. Slowly turn the water shut-off valve counter-clockwise to turn the water back on. Let the tank fill completely. Check for leaks at the supply line connection. Flush the toilet multiple times and use a flashlight and paper towels to carefully inspect around the entire base of the toilet for any signs of water. If it remains dry and the toilet is stable, the installation is complete.
Common Problems
Tighten the tank bolts alternately and just enough to create a stable, non-wobbling seal. Overtightening can easily crack the porcelain tank or bowl.
Solution: To avoid this issue: Be mindful of this warning and take appropriate precautions.
Hand-tighten only. Using a wrench on the plastic locknut or supply line connector can cause cracking and lead to flooding.
Solution: To avoid this issue: Be mindful of this warning and take appropriate precautions.
Toilet doesn't flush properly after tiling due to incorrect water levels.
Solution: The new fill valve may have an adjustment knob to control the amount of water that refills the bowl versus the tank, allowing you to fine-tune the flush performance.
Stripped plastic threads from overtightening the water supply line.
Solution: Hand-tightening the water supply line is often sufficient to prevent leaks without damaging the plastic threads.
Be prepared for some residual water to spill when you lift the tank. Have towels ready on the floor.
Solution: To avoid this issue: Be mindful of this warning and take appropriate precautions.
The porcelain tank can be heavy and is very fragile. Handle it with care to avoid dropping or cracking it.
Solution: To avoid this issue: Be mindful of this warning and take appropriate precautions.
Water damage from residual toilet tank and supply line contents during installation.
Solution: Have a bucket and towels ready to catch any residual water from the tank and supply line.
Frequently Asked Questions
Why can't I just use a thicker or double wax ring instead of a flange extender after tiling?
While a thicker wax ring might seem like a quick fix, it creates an unstable and often unreliable seal. The toilet needs a solid, level surface to sit on for a secure, long-lasting, and leak-proof connection. An extender properly raises the flange to the new floor height, ensuring stability and preventing costly leaks caused by a wobbly toilet or compromised wax seal.
What are the most common mistakes beginners make when installing a toilet flange extender, and how can I avoid them?
A common mistake is not thoroughly cleaning and preparing the existing flange surface, which can prevent a good seal. Another is not properly sealing the extender to the original flange, leading to leaks. Always ensure the original flange is free of old wax and debris, and apply a generous, continuous bead of 100% silicone sealant or use a specialized gasket between the two parts for a watertight connection.
How difficult is this project for a beginner, and how long should I expect it to take?
This project is rated as beginner difficulty because it primarily involves careful measuring, sealing, and bolt installation rather than complex plumbing. For a DIY novice, you should allocate 2-4 hours, including the time to remove and reinstall the toilet, ensuring you don't rush important sealing steps. Having all tools and materials ready beforehand will significantly speed up the process.
What specific safety precautions should I take when working on this project, especially since it involves plumbing?
Always turn off the water supply to the toilet and flush it to empty the tank and bowl before starting. Wear work gloves to protect your hands from unsanitary conditions and potential cuts. Be cautious when lifting and moving the heavy toilet; always lift with your legs and consider getting assistance to prevent back injuries.
Do I really need to apply silicone sealant between the existing flange and the extender, or are the bolts enough?
Yes, applying a generous and continuous bead of 100% silicone sealant or using a wax-free gasket between the existing flange and the extender is crucial. The bolts provide mechanical security, but the sealant creates a watertight and gas-tight barrier, preventing both water leaks and sewer gas from escaping into your bathroom. Skipping this step is a primary cause of future problems.
What if my existing flange is damaged, corroded, or broken? Can I still use an extender?
If your existing flange is severely damaged, such as being cracked, significantly corroded, or broken, an extender alone may not provide a reliable or lasting seal. In such cases, it's often better to first repair or replace the entire flange for a solid foundation. Consult with a plumbing professional or look into specific flange repair kits designed for more extensive damage before attempting to install an extender.
