How to Install and Replace a Toilet

One of the best ways to upgrade your bathroom is to install new plumbing fixtures like toilets. There are so many stylish and functional toilet options available today, it makes no sense to continue with an old, outdated toilet. While many people are comfortable tackling a tile job, switching out plumbing fixtures can make even the most hardcore DIY’er pause. Are you DIY obsessed enough to contemplate putting in a new sink or installing a toilet? This level of DIY is not for everyone; installing a new toilet can be intimidating. Never fear, we will review how to replace a toilet, including removing the old toilet and how to install a toilet. Each toilet is a little bit different. Follow the manufacturer’s installations instructions if they differ from the instructions listed below.

How to Replace a Toilet

Tools and Parts Needed:

  • Adjustable or open ended wrench
  • Hacksaw
  • Tape measure
  • Putty knife
  • Wax ring
  • Bucket
  • Sponge
  • Old rag or towel
  • New Toilet, seat
  • Tank bolts, washers, and nuts

Check Specs

Preparatory Steps

Carefully measure your new toilet to make sure it will fit in the existing space. You will want to measure the distance between the wall and the waste line to make sure the new toilet will fit. You do not want to wait until you have removed your old toilet to find out that the new one will not fit. Also measure the length of the toilet overall to make sure it will fit comfortably into your bathroom, especially if you are switching from a shorter round bowl to a longer elongated bowl. Before you can get started replacing a toilet, the first step is to turn off the water supply to the toilet.

Draining the Toilet

Now that the water is turned off at the shutoff, remove water from the toilet bowl by flushing the toilet. This will remove most of the water from the tank and bowl. To remove the remaining water, use a force-cup plunger to force it down the drain line. You can then remove any remaining water from the tank with a sponge and a bucket. Finally, disconnect the water supply line from the base of the tank.

Remove the Old Toilet

If you have a two piece toilet and are working alone, disconnect the tank from the bowl before disconnecting and removing the bowl. It is easier to lifting each piece separately then to remove it all at once.
To begin removing the old toilet, pry off the trim caps at the base of the toilet. Loosen and remove the nuts and washers on the bolts that secure the base of the toilet to the floor. You might find that the nuts are rusted. If so, you will need to cut the nuts off with a hacksaw.
When the nut and washer on each side of the bowl have been removed, begin gently rocking the toilet back and forth. Continue until you can lift it the toilet bowl free. Remove the toilet bowl and set it aside. You might want to put on gloves at this point. What you have exposed is an open line to the sewer line. Prevent sewer gasses from coming into your home by stuffing a large rag or old towel into the hole. DO NOT LET THE RAG FALL IN. You will need to remove the old wax seal. Use a putty knife to carefully scrape away the old wax. Make sure it is all gone and clean the area with mineral spirits.

Install the New Wax Seal

Now that the flange is exposed, check to see that the flange is intact and not cracked. If the flange is cracked or otherwise damaged, call a professional plumber. It is critical to have an intact flange. If the flange is ok, remove the rag or covering from the hole. DO NOT FORGET TO REMOVE THE RAG BEFORE INSTALLING THE NEW WAX SEAL. This is a big deal. Remove the closet bolts from the flange. Install the new wax seal pressing firmly without pressing it out of shape. Hook the new closet bolts into the slots on the flange.

Have a Two Piece Toilet? Attach the Tank and Bowl

If you have a two piece toilet, attach the tank and bowl to assemble the new toilet. If you have a one piece toilet, skip this step. To attach the tank and bowl, slide the tank bolts through the opening in the bottom of the tank. Line up the shank of the bolts with the holes in the bowl, and drop the tank into place. Secure the tank to the bowl by tightening a nut onto each tank bolt. Evenly tighten all the nuts until the tank rests firmly on the bowl.

Position and Secure the New Toilet

Line the closet bolts up with holes in the base of the toilet and place your new toilet onto the flange assembly. Gently press the toilet in place to form a seal with the new wax ring.Once the toilet is firmly in place, attach the washers and nuts onto each bolt. Tighten the nuts just enough to keep the toilet from rocking at all, but do not over tighten the nuts. Place the new trim caps over the bolts. If the bolts extend too far over the top of the washers and nuts to be able to place the trim caps on, cut off the excess length of the bolts with a hacksaw. Attach the new toilet seat and lid to the bowl with mounting bolts. Connect the water supply line to the bottom of the tank with slip-joint pliers.
Installing a toilet is not difficult, but it is important to follow all the steps carefully and to get the job done correctly. If you do not understand how to install a toilet, it is better to seek the advice of a professional plumber rather then perform the job incorrectly. Especially use caution if your household only has one toilet. If you run into a problem, Benjamin Franklin Plumbing provides 24 hour emergency plumbing services. Hiring a professional plumber makes replacing a toilet easy.