How to Install a Toilet
Step-by-step guide to replacing a toilet yourself
⚡Quick Answer
Shut off the water supply valve, flush the tank empty, then remove and dispose of the old toilet safely. Set a new wax ring on the floor flange, lower the new toilet onto the bolts, connect the water supply, and check for leaks before calling the job done.
Step-by-Step Guide
Remove the Old Toilet
Shut off the water supply valve behind the toilet, flush to empty both the tank and bowl, then disconnect the supply line at the bottom of the tank. Unscrew the floor bolt caps and nuts, rock the toilet gently to break the old wax seal, and lift the whole unit straight up off the floor.
Install the Wax Ring
Inspect the floor flange for cracks or corrosion and repair it before continuing, because a damaged flange leads to chronic leaks. Place a new wax ring over the flange with the tapered side facing up, pressing it lightly so it stays centered.
Set the Toilet
Carefully lower the toilet over the floor bolts, using the bolt holes as guides to position it precisely before any weight is applied to the wax ring. Once aligned, press straight down firmly and evenly with your body weight to fully compress the wax seal — a good seal is critical to prevent sewer gas and leaks.
Connect and Test
Hand-tighten the flange nuts alternating sides so the toilet seats evenly, then snug them with a wrench — check that the toilet does not wobble at all. Reconnect the water supply line, turn the shutoff valve back on, and carefully inspect every connection point as the tank fills for the first time.
Frequently Asked Questions
Do I need to replace the wax ring every time?
Yes — always use a brand-new wax ring whenever a toilet is removed and reinstalled, even if the old one looks undamaged. A wax ring compresses permanently to form the seal, so once it has been used it cannot create a reliable second seal. Reusing an old ring is one of the most common causes of sewer odor and floor damage after a DIY toilet swap.
How tight should the floor bolts be?
Tighten the flange nuts snugly with a wrench, alternating between left and right so the toilet base compresses evenly, but stop well before maximum torque. Porcelain is brittle and cracks under uneven stress — the toilet should sit rock-solid with no wobble, which is your cue to stop tightening. If the toilet still rocks slightly after snugging the nuts, shim the base with plastic toilet shims before adding any more torque.
Can I install a toilet without a plumber?
Yes, most homeowners can complete a full toilet replacement with just an adjustable wrench, a sponge, and a bucket in two to three hours. The job becomes more complex if your floor flange is broken, the drain pipe is an unusual size, or you are also relocating the drain — those scenarios benefit from a professional. For a straightforward swap of an existing toilet on an intact flange, it is a very approachable DIY project.
What do I do if my toilet rocks after installation?
A rocking toilet almost always means the floor is uneven rather than that the bolts are too loose — do not simply crank the nuts tighter, as that risks cracking the base. Slide plastic toilet shims under the low side of the toilet base until it sits completely stable, then snap or cut off the protruding ends. Once the toilet is steady, apply a thin bead of **silicone caulk** around the base perimeter (leave a small gap at the back so any future leak is visible) to prevent the shims from shifting.