The parts you are connecting
A toilet looks simple, but it has several parts that must seal.
| Part | Job | Common problem |
|---|---|---|
| Closet flange | Anchors the toilet to the floor and meets the drain | Cracked or set too low. |
| Wax ring or gasket | Seals the toilet to the flange | Leaks if reused or misaligned. |
| Closet bolts | Hold the toilet to the flange | Overtightened bolts crack the bowl. |
| Supply line | Brings water from the shutoff to the tank | Old lines burst. |
| Shutoff valve | Stops the water for service | Stuck or leaking valve. |
Gather tools and check the flange first
Collect an adjustable wrench, a putty knife, a new wax ring or foam gasket, new closet bolts, a new supply line, a level, rags and a bucket. Then check the flange. The flange should sit flat on the finished floor and not be cracked or corroded.
A flange set below the floor surface leaves a gap that a standard wax ring cannot fill. A spacer ring or a repair flange fixes this. If the flange is broken or the floor is soft, stop, because the problem is larger than the toilet.
Remove the old toilet
Take the old one out cleanly before you set the new one.
- Shut off the water.Close the valve and flush to empty the tank.
- Disconnect the supply.Unscrew the line and sponge out the remaining water.
- Remove the nuts.Take the caps off the closet bolts and remove the nuts.
- Lift the toilet.Rock it gently to break the seal and lift with a helper.
- Clean the flange.Scrape off old wax and stuff a rag in the drain to block sewer gas.
Toilet job bigger than you thought?
Call us with what you found under the old toilet. We will tell you what the repair involves.
Call (480) 741-9332Set the new toilet
Place new closet bolts in the flange slots, set the new ring and lower the toilet straight down so it seats evenly.
- Seat the bowl.Press down firmly with a slight twist and do not rock it.
- Tighten the nuts.Alternate sides in small turns until snug. Overtightening cracks porcelain.
- Attach the tank.Follow the maker's steps for tank bolts and gaskets.
- Connect the supply.Use a new line and tighten by hand plus a quarter turn.
- Test.Open the valve, flush several times and check every joint for moisture.
Caulk around the base if you like, but leave a gap at the back so a leak can show.
Mistakes that cause leaks
Most failures trace to a few errors. Reusing an old wax ring, rocking the toilet after it seats, tightening one bolt fully before the other and using an old supply line are the usual ones. A toilet that rocks needs shims, not more tightening.
If a toilet leaks at the base after a swap, the seal is bad. Pull it and reset it with a new ring. Water that appears days later on the ceiling below is a sign the seal failed. Our toilet repair page covers running, clogged and leaking toilets.
When to hire the job out
Call a plumber if the flange is broken, the floor is soft, the drain is slow or you are adding a new toilet where none existed. New drain and vent routing is real plumbing work. See plumbing installation for new bathrooms and remodels.
Choosing the right toilet for your bathroom
The best toilet is one that fits the space and the drain. Measure before you shop.
Buy a model with a rough-in that matches your wall. A 10-inch toilet will not fit a 12-inch flange without compromise.
| Measure | How | Why |
|---|---|---|
| Rough-in | Wall to center of the flange bolts | Most are 12 inches, but check. |
| Bowl shape | Round or elongated | Elongated needs more room. |
| Height | Standard or comfort height | Comfort height suits many adults. |
| Clearance | Space to side walls and in front | Codes set minimums. |
Water use and efficiency labels
Newer toilets use much less water per flush than older ones. The EPA WaterSense label marks models that meet its water efficiency criteria. A toilet with that label can lower your water bill, especially in a house with several people.
Look at the flush rating on the tank or the box. Check that the bowl performance has been tested. If a toilet needs two flushes to clear the bowl, it saves nothing. Read independent flush tests before buying a low-cost model.
After the install: a quick checklist
Do a final check an hour later and again the next day. Look at the base for moisture, press on the tank to see whether it moves and listen for a hiss that means the fill valve is still running.
Mark the shutoff valve with a tag so everyone in the house knows where it is. Keep the old supply line out of the trash until you are sure the new connection holds.
Local note: licensing in Arizona
Arizona licenses contractors through the Registrar of Contractors. Plumbing classifications include C-37, CR-37, R-37 and R-37R. You can check a license at roc.az.gov or by calling 602.542.1525 before you hire anyone to do more than a simple swap.
For a like-for-like toilet swap by the owner, ask your building department whether a permit is needed. In Florence that is Community Development at 520-868-7575, and in unincorporated areas it is Pinal County Building Safety.
If a swap goes wrong, we can reach Coolidge and San Tan Valley along with Florence.
Source type: Arizona Registrar of Contractors (state licensing agency) and Town of Florence contact information. License classes are listed according to the Registrar of Contractors.
Questions readers ask
A first-timer should plan a few hours. The steps are simple but should not be rushed.
No. A used ring will not reseal reliably. Use a new ring every time.
Model plumbing codes such as the UPC and IPC set requirements for clearances, venting and water use. Your building department says which code applies.
Search the Registrar of Contractors site at roc.az.gov or call 602.542.1525.