Whether you’re forced to get a new toilet (ugh! Leaks!) or you’re remodeling and need one that goes with your new room, there are some points to consider first. Here’s a handy step-by-step guide to buying a new toilet and installing it.
First, measure from the wall behind the toilet to the center of bolts of the existing toilet. This is your rough-in measurement, and you need to for proper drain location. 12 inches is normal, but older homes can be a challenge so measure twice to be sure.
For smaller bathrooms, measuring from the center of the closet bolts to the walls or vanity on either side of the toilet is also necessary. You need to make sure your new toilet will fit into the space as well as make sure the drain openings line up properly.
Now, you can shop for your new toilet, but a good rule of thumb is that you don’t remove the old toilet until you have the new one ready to go.
Taking out the old toilet
Before you do anything else, turn off the water supply to the toilet by turning the knobs to off both on the supply line from the wall and attached to the toilet.
You should also remove any excess water by flushing the toilet and using a cup to scoop any remaining water from the bowl and tank.
Disconnect the supply line from the toilet. For this guide, we’ll assume the line is in good shape and will be reused.
Taking out the old toilet requires a couple of steps and will probably work best with two people.
Remove the tank from the bowl by removing the nuts off the bolts that pass through the tank at the back of the bowl. Lift the tank off and take it outside.
Make sure you have a large plastic bag – like a 30-gallon garbage bag – on hand to put the bowl in once it comes off the floor.
To remove the bowl, loosen the closet bolts that hold it to the floor and take them out. Rock the bowl side-to-side to loosen it from the wax seal. Lift it straight up and put it right on or in the garbage bag and take it outside.
Plug the drain line with a rag to prevent anything from falling into it and sewer gases from coming out.
Scrape any residual wax from the seal from the floor around the drain line.
Installing the new toilet
Insert the new closet bolts into the flange around the drain hole and make sure they’re parallel to the wall behind the toilet.
Turn the new toilet over on a towel or blanket to prevent damaging the new piece. Place the wax ring onto the waste horn and be sure it’s room temperature so it sticks to the porcelain. A cold wax ring needs to warm in order to properly seat the new bowl.
Unplug the drain line and fit the new toilet onto the closet bolts and over the drain line. Rock it gently to press the wax ring into place and tighten the nuts on the closet bolts. Alternate one side to the next to be sure the same amount of pressure is being applied to both sides of the toilet.
Install the bolt caps over the closet bolts.
If you have a 2-piece toilet you’ll need to install the new tank.
Place the large, rubber gasket over the outlet on the bottom of the tank and insert the tank mounting hardware with rubber washers from inside the tank.
Fit the tank to the back of the bowl, threading the mounting bolts through the hole(s) on the back of the bowl.
Alternate side-to-side again to tighten the bolts, but don’t overdo it or you could crack the bowl.
Install the toilet seat and connect the water supply line to the tank. Turn both ends of the supply line back on and wait for the tank to fill before flushing to be sure there are no leaks.