How to Bolt a Flange to the Floor

Toilet flanges install in the floor underneath the toilet bowl.

Installation of a new toilet involves a new flange and a wax ring to seat and seal the toilet bowl to the floor in a bathroom. Cracked flanges will leak toilet water onto the floor around the toilet base and need replacement. Toilet flanges attach to the soil pipe under the house, provide a stable base for the wax ring to seal water inside the toilet bowl and support the weight of the toilet.

Things You'll Need

• PVC cleaner
• PVC glue
• Toilet flange kit
• Drill with Phillips bit
• Toilet wax ring
• Adjustable wrench

Instructions

1. Wipe a liberal amount of PVC cleaner on the inside of the toilet flange and on the outside of the soil pipe. Apply a liberal amount of PVC glue to the same two areas. The soil pipe is the large PVC pipe in the floor.

2. Set the toilet flange on the floor over the soil pipe with the two slots for bolt retainers on the left and right sides of the soil pipe. Twist the flange onto the soil pipe.

3. Place a screw out of the toilet flange kit in one of the screw holes around the flange. Use a drill to screw the screw entirely into the flange so the screw head is slightly lower that the top of the flange pointing up. Repeat this process for the other 5 screws in the flange.

4. Slide a bolt head into the slot on the left side of the flange with the threads pointing up. Place the second bolt in the right side of the flange in the same manner.

5. Slide a washer onto each of the two bolts.

6. Place a toilet wax ring flat side down onto the flange so that the wax ring partially covers the bolt heads on the flange. Press the wax ring down firmly to seat it.

7. Set the toilet bowl onto the flange while lining up the bolts on each side of the flange with the boltholes in each side of the toilet bowl.

8. Place one hand on each side of the toilet bowl and press down firmly onto the wax ring.

9. Place a nut on each bolt and hand tighten in a clockwise direction. Place an adjustable wrench on each nut and turn clockwise to tighten each nut fully on the bolt.

Tips & Warnings

• Install a new wax ring when removing a toilet bowl for repairs. The wax rings forms a protective barrier at the bottom of the toilet bowl to prevent leaking around the toilet base.

• Home improvement centers carry toilet flanges and wax rings.

• It is helpful to have a second person to lift the toilet bowl into place and line the boltholes up on the bolts.

• Place the toilet flange onto the soil pipe immediately after applying PVC glue. This prevents the glue from drying before the flange is in place with a bolt slot on each side. A crooked flange will make the toilet crooked when the bowl attaches to the bolts on each side.

References

• This Old House: How To Install A Toilet