Installing Toilets, the 12 Step Method

If your toilet, or water closet, is old or in need of repair, you may find it’s cheaper to install a new one than to patch up the existing one, especially if you do the job yourself. Installing a new toilet is actually a rather simple plumbing procedure that can be accomplished in just a few steps. To install the new toilet, you’ll need a new toilet gasket and two 5/16-inch bolts to mount the bowl to the floor flange, but most of the required parts will be included with the new toilet.

When removing the old toilet, shut off the water supply to the tank and flush the toilet. Use a bucket or cloth to remove any leftover water in the tank and bowl. Using a pair of pliers or small pipe wrench, remove the nut connecting the water line to the ballcock valve at the bottom, left side of the tank.

Use a small crescent wrench to remove the two nuts that hold the bowl to the floor flange. Once the nuts are removed, lift and remove the old toilet.


1. The exposed flange is the mounting base for your new toilet. Discard the old bolts.


2. First, place the two new, 5/16-inch bolts in the holes located on the sides of the exposed flange, with the bolt heads inside the flange. Position the bolts straight up and across from each other. Then put the new toilet gasket (wax ring) on the flange, with the flat side pointing up, if tapered.


3. Lower the new bowl straight down, centering it on the wax ring and making sure both bolts come though the holes on each side of the bowl. Apply pressure straight down, pushing the bowl over the ring and flange, squeezing the wax to create a seal and mounting the bowl flush with the floor.


4. Add washers and nuts to the protruding bolts and tighten until snug. (Over-tightening can crack the bowl).


5. To install the toilet’s tank, push two 5/16-by-3-inch mounting bolts through the small holes on the tank’s bottom. Place rubber washers just beneath the bolt heads inside the tank to create a watertight seal. Add nuts and washers to the bolts on the underside of the tank and tighten until snug.


6. Apply the sponge-rubber gasket (with small side down if beveled) over the discharge tube where the tank sets on the bowl.


7. Set the tank on the bowl, threading the bolts into the bolt-holes on the bowl and sandwiching the gasket between the tank and bowl.


8. Add metal washers and nuts to the bolts where they extend downward from the bottom of the bowl. Hold the tank level and tighten. It may help to hold each bolt stationary with a screwdriver inside the tank while backing up the nut with a crescent wrench on the outside of the bowl.


9. Install a new toilet-flush handle by screwing the handle to the lift arm, through the handle hole in the tank. Toilet handles are threaded in reverse. Connect the lift arm to the chain of the flushing ball/flapper inside the tank.



10. Bolt the new toilet lid to the bowl.


11. Install a new water line from the wall or floor fixture to the feed valve on the underside of the tank. Turn on the water and check for leaks. Give it a couple of trial flushes. If your toilet holds water, tighten the bolts that hold the bowl to the floor. If there’s any instability between the tank and bowl, or bowl and floor, use hard rubber shims, usually available at hardware stores, to adjust minor spacing problems and ensure a smooth ride.


12. Once everything is in place and adjusted, cut the ends off the bowl-mounting bolts to accommodate the plastic bolt caps. You may want to caulk the base of the bowl to create a waterproof seal, protecting the floor and providing additional stability.

Put on the tank cover, and your new toilet is ready for its maiden voyage.

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