Replace a toilet
Swap a standard two-piece toilet, make a fresh floor seal and check for leaks.
Home · 2–4 hr · Medium
Before you start
Use a helper to lift porcelain; protect hands and eyes. Prove the shutoff works before disconnecting. Stop for cracks, soft flooring, a loose flange or corroded fasteners that cannot be removed safely. Cover the open drain with a retrievable rag while working, and remove it before installing.
Tools and materials
- Compatible two-piece toilet, seat, mounting hardware, floor seal, closet bolts, plastic shims and specified base sealant
- New compatible supply connector, adjustable wrench, tape measure, plastic scraper, screwdriver and small level
- Bucket, sponge, gloves, eye protection and old towels
Check the problem
Check the fit before buying
Measure from the finished wall—not the baseboard—to the floor-bolt centerline. Check bowl length, door swing and supply clearance against the new toilet drawing.
Rule out damage beneath the toilet
Look for rocking, stained flooring and moisture. Confirm the supply valve shuts off. Hidden flange damage can only be assessed after removal; be prepared to pause the replacement.
Steps
Isolate and empty the old toilet
Close the shutoff, flush and confirm the tank does not refill. Sponge out the remaining tank and bowl water. Put the lid on a padded surface and place a bucket beneath the supply connection.
Disconnect and remove the tank
Disconnect the supply into the bucket. Support the tank while removing its mounting nuts. With a helper, lift it clear and place it on padding without loading the projecting fittings.
Lift the bowl and remove the old seal
Undo the floor nuts, cut any base caulk and lift the bowl with a helper. Set it on protection. Scrape old wax into a bag without dropping debris into the drain; temporarily cover the opening.
Inspect the flange and rehearse the fit
The flange must be sound, securely fixed and compatible with the seal at its installed height. Dry-fit the bowl without the seal; mark needed plastic shims. Stop for damage or a height mismatch rather than stacking seals.
Fit the bolts and new seal
Lift the bowl away. Install the closet bolts and remove the drain covering. Fit one compatible seal exactly where its instructions specify. Keep the drain passage clear; do not reuse compressed wax.
Lower, stabilize and secure the bowl
With a helper, lower the bowl straight over the bolts. Press it down evenly and fit the marked shims. Tighten floor nuts gradually and evenly only as specified. Do not pull rocking porcelain flat with the nuts. If lifted after seating wax, renew the seal.
Assemble the tank and reconnect
Fit the tank gasket, hardware and seat in the new toilet’s order. Keep the tank level while tightening alternately. Connect the new supply without kinks, using its specified tightening method; washer-sealed connectors do not need thread tape.
Refill, flush and check every joint
Open the valve slowly. Check supply and tank connections, then flush several times while inspecting the base with dry tissue. The toilet must not rock. After successful testing, seal the base as required by the toilet instructions and local rules; observe sealant cure time.
Supply, tank and base remain dry through repeated flushes; the toilet is stable and fills to its marked level.
Tips
Do the dry fit first
Find rocking before compressing the seal. Shims support the bowl; caulk is not a structural shim.
One seal matched to the flange
Wax-free seals have their own height and reuse rules. Do not substitute a second wax ring for flange repair.
Check again after use
Inspect the supply, tank bolts and base after the next few flushes. Shut the water off if a leak returns.