Replacing a toilet is one of the most satisfying weekend plumbing jobs a homeowner can take on – it is mostly muscle and patience, not specialized skill, and a new toilet runs about an hour once you have done it. As a licensed plumber, here is the full sequence, including the two steps people rush that cause leaks later.
What you will need
- The new toilet and a fresh wax ring (never reuse the old one)
- An adjustable wrench, a putty knife, and a sponge and bucket
- A new braided supply line and new closet bolts (cheap insurance)
- Shims and a level, plus a toilet seat if one is not included
Step 1: Shut off the water and empty the tank and bowl
Turn off the supply at the shut-off valve behind the toilet, then flush and hold the lever to drain the tank. Sponge out the remaining water in both tank and bowl – the more you remove now, the less mess later. Disconnect the supply line.
Step 2: Remove the old toilet
Pop the caps off the floor bolts and unscrew the nuts. Gently rock the toilet side to side to break the wax seal, then lift it straight up (get a helper – a toilet is awkward and heavy) and set it on an old towel. Stuff a rag in the open drain to block sewer gas while you work.
Step 3: Scrape the flange and check it
Scrape every bit of old wax off the closet flange with a putty knife. Inspect the flange itself – it should sit level with or just above the finished floor and not be cracked. A broken or sunken flange is the most common cause of a wobbly, leaking toilet, and it is far easier to address now than after the new toilet is set. Remove the rag, drop in new closet bolts.
Step 4: Set the new wax ring and toilet
Press a new wax ring onto the flange (or onto the toilet horn – either works). Lift the new toilet, line the bolt holes up with the closet bolts, and lower it straight down onto the wax. Then – and this is the step people skip – press your weight down evenly to fully compress the wax. Do it once; lifting and re-seating ruins the seal.
Step 5: Bolt it down, connect, and test
Hand-tighten the nuts, then snug them with a wrench in small alternating turns. Stop the moment there is resistance – overtightening cracks the base. Shim any wobble, connect the new supply line, turn the water on, and let the tank fill. Flush several times and watch the base and supply connection for any seep. Caulk around the base last.
Should you DIY it or call a pro?
A straight swap on a sound floor is a great DIY job. Call a plumber if the flange is broken or below floor level, if the subfloor around the toilet feels soft (that means a long-standing leak and possible rot), or if the shut-off valve is seized. For the budget side of the decision and what a pro charges, see cost to replace a toilet, shop models in best toilet, and gut-check the call with when to DIY vs call a plumber.
Frequently asked questions
How long does it take to replace a toilet?
For a straightforward swap on a sound floor, plan on about an hour once you have your tools and parts ready. Your first one may take closer to two hours. The time-consuming parts are draining and removing the old toilet and scraping the flange clean – the actual setting of the new toilet is quick.
Do I need a new wax ring every time?
Yes. Always use a fresh wax ring – never reuse the old one. Once a wax ring has been compressed and broken loose, it will not reseal reliably, and a failed seal leaks under the floor where you cannot see it until there is damage. A wax ring costs a few dollars; reusing one is the most common cause of a re-leak.
How tight should the toilet bolts be?
Snug, not cranked. Tighten the nuts in small alternating turns until you feel firm resistance, then stop. Porcelain cracks easily, and overtightening the closet bolts is a classic way to ruin a brand-new toilet. If the toilet still rocks, shim it rather than tightening further.
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