How to Remove a Toilet Flange: PVC, Cast Iron and Glued Types

A cracked or rusted toilet flange is the hidden reason many toilets rock, leak at the base or refuse to seal no matter how many wax rings you try. Knowing how to remove a toilet flange starts with identifying what you have, because a screwed-down PVC flange comes out in ten minutes while a glued-in or cast iron flange can take an afternoon. The method changes completely with the material and with how the flange is attached to the drain pipe.

Part of our Bathroom Remodeling & Flooring guide — explore the full guide →

Here is the short version. Pull the toilet, stuff a rag in the drain opening, and look at the flange. If it is plastic and screwed to the subfloor with no glue joint, remove the screws and lift it. If it is PVC or ABS glued over or inside the pipe, you will cut it out with an internal pipe cutter or an oscillating multi-tool and then clean the pipe for a new flange. If it is cast iron, you either break off the ring and chip out lead and oakum or cut the flange free and transition to a new fitting.

Plan on at least two to four hours for the whole job if you have not done it before, and keep the drain plugged the entire time. An open 3 or 4 inch drain lets sewer gas into the house and swallows any tool or screw that falls toward it.

How to Remove a Toilet Flange: Identify the Type First

Every decision about how to remove a toilet flange follows from the flange material and the connection style. Spend five minutes looking closely before you buy parts or start cutting.

• Screwed PVC or ABS flange on top of the floor. White (PVC) or black (ABS) plastic ring with four to six screws into the subfloor. Some sit over the pipe with a glue joint underneath, so check whether the hub disappears inside the pipe or slips over it.
• Glued-in plastic flange. The flange body is solvent-welded inside or over the closet bend. Removing the screws does nothing; the flange will not budge.
• Plastic flange with a metal ring. A plastic body with a stainless or galvanized swivel ring. Often the ring is what rusted, and a repair ring may solve the problem without full removal.
• Cast iron flange. Heavy, dark, often scaled with rust. Older ones are leaded onto a cast iron pipe with packed oakum and poured lead. Newer ones may be bolted or set with a compression gasket.
• Compression or expanding-gasket flange. Sits inside the pipe with a rubber seal tightened by screws on top. Loosen the screws and it pulls out.

Also measure the flange height relative to the finished floor and note the bolt slot condition. If the flange is sound and only the bolt slots broke, a bolt-on repair ring or spanner plate is faster and cheaper than removal.

Tools and Materials

• Adjustable wrench, putty knife and a stiff scraper for the old wax ring
• Large sponge and bucket to empty the tank and bowl
• Old rag or a test plug sized for 3 or 4 inch pipe to block sewer gas
• Screwdrivers and a drill/driver for flange screws
• Oscillating multi-tool with a bi-metal blade, or an internal pipe cutter for plastic
• Cold chisel, ball-peen hammer and a small pry bar for cast iron
• Reciprocating saw only if you have access from below
• Nitrile or work gloves, safety glasses, and a dust mask or respirator
• New flange matched to your pipe, new wax ring or wax-free seal, new closet bolts
• Shop vacuum and disinfectant spray for cleanup

Step 1: Remove the Toilet

1. Shut off the water at the supply valve behind the toilet, then flush to empty the tank. Hold the handle down to drain as much as possible.
2. Sponge the remaining water out of the tank and bowl into a bucket. Wear gloves for this.
3. Disconnect the supply line at the tank fill valve. Keep a small towel under it for drips.
4. Remove the caps and nuts from the closet bolts at the base. Rusted nuts can be cut with a small hacksaw or oscillating tool.
5. Rock the toilet gently side to side to break the wax seal, then lift straight up. A two-piece toilet weighs 60 to 120 pounds and is awkward, so get a helper to lift it.
6. Set the toilet on its side on cardboard or an old towel, away from foot traffic.

Immediately plug the drain opening with a rag tied to a length of string, or with a rubber test plug. The string keeps the rag from disappearing into the pipe. Leave the plug in until the new toilet is ready to set, removing it only when you need to see inside the pipe.

Step 2: Scrape the Wax and Inspect

Scrape all old wax off the flange and floor with a putty knife. Wax smears everything it touches, so wrap scrapings in newspaper and toss them. Once clean, you can see the screws, the hub and whether there is a glue line. Shine a flashlight into the pipe: a seam a short distance down tells you the flange hub is glued inside the pipe, while a flange that sits over the outside of the pipe will show its edge at the top.

Step 3: Remove a Screwed PVC or ABS Flange

If the flange is a slip-on type with only screws holding it, back the screws out and lift the flange off. Some come up after you break a small amount of caulk or old sealant. If the flange spins but will not lift, there is a glue joint and you need the cutting method.

For a compression or expanding-gasket flange, loosen the screws on top that squeeze the rubber seal, then wiggle the unit up and out. These are designed to be removable.

Step 4: Cut Out a Glued-In Plastic Flange

Glued-in flanges are the most common type in homes built since the 1970s. The goal is to remove the flange without damaging the pipe so a new flange can glue or compress into place.

Flange glued over the outside of the pipe

Remove the floor screws. Cut through the flange hub vertically in two or three places with an oscillating multi-tool, stopping before you reach the pipe wall. Then use a chisel to split the remaining sections and peel them off. Work slowly; the pipe needs a clean, round outer surface for the new fitting.

Flange glued inside the pipe

This is where an internal pipe cutter or inside-pipe flange remover earns its keep. These drill-powered tools cut the old hub away from the inside, leaving the pipe wall intact so a new inside-fit flange or compression flange can go in. An oscillating multi-tool with a plunge blade can also make vertical relief cuts in the hub, which you then collapse inward with a screwdriver and pliers. Take thin bites; cutting through the pipe wall turns a flange job into a pipe repair under the floor.

If the hub is glued to the pipe and the pipe itself is short, sometimes the best option is to cut the pipe flush with the subfloor and use an inside-fit compression flange. That avoids opening the floor or ceiling below.

Step 5: Remove a Cast Iron Flange

Cast iron flanges are heavier work and need more care. Older ones were joined to the pipe with packed oakum and molten lead, and that lead is still there.

1. Remove any screws or bolts into the floor. They are often rusted; penetrating oil and patience help.
2. Score the flange ring with a cold chisel at several points, then strike sharply to crack sections off. Cast iron fractures rather than bends. Wear safety glasses and gloves because shards fly.
3. With the ring off, you will see the lead and oakum joint inside the pipe hub. Chip out the lead with a narrow chisel and pry it free in pieces. Pick out the oakum below it.
4. Once clear, install a cast iron compression flange or a rubber transition fitting suited to the pipe.

Never melt old lead joints with a torch at home. Collect lead pieces in a bag, wash hands thoroughly, and keep children and pets away from the work area. Many local waste programs take lead as scrap metal or household hazardous waste.

Safety: Sewer Gas, Lead, Asbestos and Solvents

The drain must stay plugged whenever you are not actively working in it. Sewer gas contains hydrogen sulfide and methane, smells foul and can cause headaches in a small bathroom. Open a window and run the exhaust fan.

Homes built before 1978 may have lead paint on baseboards and trim near the toilet, and cast iron drains often have lead joints. Older sheet vinyl, vinyl tile, the mastic under it and some flooring adhesives from before the 1980s can contain asbestos. If the floor around the flange is original to an older home, have the flooring and adhesive tested before you cut or scrape it. Do not dry-sand suspect material.

PVC primer and solvent cement for the new flange give off strong, flammable vapors. Ventilate well, wear gloves and eye protection, keep vapors away from water heater pilot lights, and never mix drain cleaners or bathroom cleaners while the drain is open. Bleach combined with ammonia or acidic cleaners releases toxic gas.

Troubleshooting Common Problems

• The pipe cracked during removal. If the crack is near the top, cut the pipe below the damage and use a coupling or an inside-fit flange. If it runs below the floor, access from beneath may be needed.
• The flange is rusted to the floor. Cut the screw heads off with an oscillating tool and pull the flange; extract the shanks later or drive them flush.
• The subfloor around the flange is rotted. Soft, dark or crumbling wood means long-term leaking. Cut out and replace the damaged section before installing a new flange.
• The new flange sits too low. The flange should rest on top of the finished floor. Use a flange extender or spacer rings rather than stacking wax rings.
• You cannot tell PVC from ABS. Match the new flange to the pipe color and stamp. Mixing them requires a specific transition cement or a mechanical fitting.

Cost to Replace a Toilet Flange

A replacement plastic flange typically runs $10 to $30, a compression or inside-fit flange $20 to $50, and a cast iron compression flange somewhat more. A wax ring and bolts add a few dollars. An internal pipe cutter is often the priciest item, and renting or borrowing one makes sense for a single job. Plumbers usually charge in the range of $150 to $400 for a flange replacement, and more if the subfloor needs repair or a cast iron joint has to be cut out.

When to Call a Licensed Professional

Call a licensed plumber if the drain pipe is cracked below the floor, if the cast iron pipe crumbles when you chip at it, or if you need to cut into a closet bend you cannot reach. Structural damage to joists, extensive subfloor rot and any job that changes drain routing should go to a pro, and some areas require a permit for work beyond a straight flange swap. Hire a certified abatement contractor if asbestos testing comes back positive, and use lead-safe practices or a certified renovator for lead.

Once the new flange is installed and screwed down to the subfloor, set a fresh wax ring, lower the toilet straight down with your helper, tighten the closet bolts evenly, reconnect the supply and check for leaks after a few flushes.