A one-piece toilet is easiest to install; however, it's also more expensive than a two-piece.You may want to consider purchasing a higher toilet as well. You'll find some toilets sit a full 1-1/2” higher than standard toilets. Higher toilets are great for older people with limited mobility. However, you're going to want a smaller toilet in the house somewhere if you have children. Remember to measure the distance between the wall and the drain underneath the toilet. Any length, between 11” and 13” is considered standard. This is the most important measurement.
Removing the old toilet:
Turn off the shutoff valve and flush the toilet to make sure the tank and bowl are empty. Use a sponge on the inside of the tank to make sure it's completely dry.
Then, disconnect the water supply at the shutoff valve and the tank.
Once the water is off, you must remove the tank from the bowl. You will find a few nuts and bolts holding these units together. After taking out the bults, carefully set aside the tank. Now, you're ready to remove the bowl. Pull off the trip caps on the floor bolts. Using an adjustable wrench, remove the nuts and bolts. These may be difficult to remove as they could be extremely old. You may need a hacksaw blade to get them off.
With the bowl sealed to the floor, move it back and forth to break the wax ring. Set the bowl aside, and scrape away any excess wax. You'll also want to clean the area with a stiff wire brush and disinfectant.
Finally, put a rag in the hole to prevent any sewer gas from leaking into the bathroom.
Installing the New Toilet:
Turn the new bowl upside down and apply a new wax ring. You'll also want to place a new sleeve over the drain horn. Check to see if the floor bolts point straight up.
Lift the toilet, and drop it over the floor bolts. Press down firmly to compress the wax ring and make a tight seal. Now, you can tighten the bowl to the floor with an adjustable wrench. Don't overtighten because you could crack the base. You may replace the trim caps and get ready to install the tank.
Place the handle, ballcock and flush valve inside the tank. Flip the tank upside down and place the spud washer over the bottom tailpiece.
Now, gently set the tank on the toilet lining up the bottom tailpiece to the water inlet opening. Connect the supply tubing to the valve and then to the ballcock tailpiece.
Screw on the coupling units until they're snug. Flip on the water, and the tank should fill.
To finish, you also need to install the new cover. Place the seating bolts onto the mounting holes. Tighten the mounting nuts onto the seat bolts (until snug).
Installing a toilet can be a simple process; however, make sure you measure correctly to avoid extra hassles.