New Toilet Install: A Step-by-Step Guide for Homeowners
Learn how to perform a new toilet install with this comprehensive guide for homeowners and DIY enthusiasts. From planning and prep to testing and sealing, get tools, steps, and safety tips for a leak-free result.
You will complete a new toilet install by safely removing the old unit, preparing the flange, setting a wax ring, bolting the new toilet, and reconnecting the water supply. Expect a 1.5–3 hour project for a typical bathroom. Use the right flange height and sealant, and verify the fit before testing.
Planning and prepping for a new toilet install
A successful new toilet install starts with careful planning. You’ll decide on the toilet type (elongated vs round, one-piece vs two-piece), verify rough-in distance, and inspect the flange and floor for solid support. According to Install Manual, taking time to measure and confirm compatibility reduces surprises once you remove the old unit. Before you buy, check local code requirements and manufacturer installation instructions to ensure your chosen model fits your plumbing and bathroom layout. Key planning steps include choosing style, checking rough-in distance, inspecting flange condition, and selecting a gasket kit that matches your flange height. This prep work matters because a poorly planned install can lead to leaks, wobble, or misalignment with the existing plumbing. The Install Manual team emphasizes documenting measurements and keeping a small parts kit handy to avoid mid-task trips to the hardware store.
- Choose style: elongated vs round front; one-piece vs two-piece
- Check rough-in distance: floor-to-drain center distance, and distance from wall to flange
- Inspect flange: height, integrity, and secure mount
- Decide on wax ring and gasket kit compatibility with your new toilet
Tools & Materials
- Wax ring (standard size)(Choose size compatible with the toilet and flange. Consider wax-free alternatives if preferred.)
- Closet bolts (2, brass or stainless)(Use corrosion-resistant bolts and ensure they match flange holes.)
- Toilet flange(Ensure the flange is secure; replace if cracked or recessed.)
- Adjustable wrench(For loosening/tightening nuts on water supply and bolts.)
- Screwdrivers (Phillips and flathead)(For tank bolts and cover plates.)
- Putty knife(Clean old wax and debris from flange and floor.)
- Silicone sealant or bathroom caulk(Seal around the base after seating the toilet.)
- Level(Check that the toilet sits evenly on the floor.)
- Bucket, sponge, towels(Clean spills and remove standing water.)
- Teflon tape (plumber’s tape)(Optional for threaded connections on supply line.)
- New flexible supply line(Replace if old line leaks or is stiff.)
- Safety gloves(Protect hands during removal and installation.)
- Shop vacuum or towel to absorb water(Helps keep the work area dry.)
Steps
Estimated time: Estimated total time: 1.5–3 hours
- 1
Shut off water and drain
Locate the shut-off valve near the toilet and turn it clockwise to close. Flush the toilet to drain most of the water, then use a sponge to remove any remaining moisture from the bowl and tank bowls. This prevents splashing when you disconnect the supply line.
Tip: Have towels ready; confirm the valve is fully closed before removing connections. - 2
Disconnect the water supply line
Place a bucket under the coupling nut to catch residual water. Use an adjustable wrench to loosen the nut on the supply line connected to the tank. If the nut is stubborn, apply a little penetrating oil and wait a few minutes before trying again.
Tip: If the nut spins, hold the nut on the valve with one wrench while loosening the line with another. - 3
Remove the tank bolts (for two-piece toilets)
Using the wrench, loosen the bolts securing the tank to the bowl and lift the tank straight up. If you have a one-piece toilet, skip to step 4. Place the tank on a soft surface to avoid chipping.
Tip: Keep the bolts and washers in a labeled container for reassembly if you reuse the tank. - 4
Remove the bowl and disconnect the flange
Loosen the closet bolts at the base of the bowl and rock the bowl gently to break the seal, then lift it away from the flange. Clean any residual wax from the flange area and floor with a putty knife. Inspect the flange for cracks or damage and replace if needed.
Tip: Be prepared for a small amount of residual water; use towels to keep the area clean. - 5
Prepare the flange and floor
If the existing flange is damaged or recessed, replace it or install a flange extender as required. Ensure the flange sits flush with the finished floor. Clean the area so the new seal will seat properly.
Tip: A stable flange prevents wobble and leaks later on. - 6
Position the wax ring and bolts
Place the wax ring on the flange (or on the toilet horn if you prefer) and align the closet bolts with the bolt holes. If you’re using a flange extender, install it per the manufacturer’s instructions before placing the wax ring.
Tip: Center the ring to ensure a uniform seal and to prevent tilting. - 7
Lower the new toilet onto the bolts
Carefully lower the toilet onto the bolts, aligning the holes with the bolts. Apply even pressure to seat the base against the floor without tilting. Leave the toilet to settle for a moment before tightening.
Tip: Use slow, even pressure to avoid cracking the porcelain. - 8
Bolt the toilet down securely
Tighten the nuts hand-tight, then snug them with a wrench in a star pattern. Do not overtighten; this can crack the porcelain or crack the wax seal.
Tip: Check for lateral movement; the toilet should be stable without rocking. - 9
Reconnect the water supply and fill the tank
Reconnect the supply line and slowly open the shut-off valve. Allow the tank to fill and stop the flow when the float valve reaches the tank’s full level. Check for leaks around the supply connection.
Tip: If you notice a leak, reseat and tighten the supply line connections carefully. - 10
Test flush and check leaks
Flush the toilet several times to verify proper operation and seal integrity. Inspect around the base and the supply line for any signs of water. If leaks persist, recheck wax ring seating and bolt tightness.
Tip: Run a full flush with a dry floor to confirm no leaks. - 11
Seal and finish the installation
Apply a bead of silicone around the base to seal against moisture and pores in the floor. Install the toilet seat, tank lid, and any trim pieces. Clean the area and dispose of packaging and waste.
Tip: Use a damp cloth to remove any excess silicone before it cures. - 12
Final inspection and maintenance
Wipe down surfaces, confirm there are no leaks after a 24-hour period, and note any required maintenance tasks (e.g., periodic wax ring checks). Take photos for reference and store replacement parts in a labeled container.
Tip: Record model and flushing performance for future maintenance.
Got Questions?
What is the first thing I should do before starting a new toilet install?
Shut off the water supply and drain the bowl. This prevents spills and makes removal safe. If you’re unsure, consult the manufacturer’s instructions.
First, turn off the water and drain the toilet to prevent spills. Then follow the step-by-step guide.
Can I reuse the old flange, or do I need a replacement?
If the flange is intact, firmly secured, and not cracked, it can often be reused. If there is damage, replace it or install an extender as needed to ensure a proper seal.
Reuse only if the flange is solid; otherwise replace to avoid leaks.
Do I need to hire a plumber for a new toilet install?
A DIY install is feasible for many homeowners with basic tools and careful attention to the flange and wax ring. If you encounter flange damage or leaks that you can’t seal, consider hiring a plumber.
You can install it yourself if you’re comfortable with basic plumbing; otherwise, seek a professional.
What type of wax ring should I use?
Choose a standard wax ring compatible with your toilet and flange height. Some newer seals offer wax-free options for a cleaner install, but follow the manufacturer’s guidance.
Pick a standard wax ring that matches your flange height and toilet model.
How do I check for leaks after installation?
Look at the base and supply line after flushing. If you see water, tighten connections gently and reseat the wax ring if necessary. Monitor for 24 hours to confirm stability.
After flushing, inspect around the base and supply line for leaks and reseat if needed.
Is silicone sealing required around the base?
Silicone sealant around the base helps seal against moisture and prevents dust intrusion. Allow the silicone to cure before use for best results.
A bead of silicone around the base helps seal and keep moisture out.
Watch Video
Main Points
- Plan before you buy to prevent fit issues
- Remove and inspect flange to avoid leaks
- Position wax ring correctly for a tight seal
- Level the toilet to prevent rocking and coating failures
- Test for leaks after full reassembly and flushing
