How to Cut Pre-Plumbed Pipe for a Basement Toilet

Pre-plumbed pipes require trimming to floor level.

Extra toilets are often added to finished basement areas to create entirely separate living areas within the home. Many of the connections are pre-plumbed when the home is built, even if no toilet is installed at the time. If your basement has a pre-plumbed basement pipe for a toilet, it typically sticks up from the floor. To install the toilet, you must trim the pipe down to the surface of the floor and then install the toilet on top of it.

Things You'll Need

• Wrench or hammer
• Rag
• Toilet flange
• Tape measure
• Pencil
• Hacksaw
• PCV cement or plumber’s adhesive
• Screwdriver

Instructions

1. Remove the cap from the top of the basement pipe by unscrewing it with a wrench. Some pipe caps simply pull out, which you can accomplish by hitting the side of it with a hammer. Stuff an old rag into the top of the pipe to stop gas from the sewer.

2. Remove a new toilet flange from the package and place it inside the top of the pipe. Place a tape measure at the base of the flange and measure up to determine the depth. Note the measurement.

3. Remove the flange and set it aside. Measure up the same distance on the pipe and draw a line all the way around the perimeter of the pipe to indicate where it requires cutting. Cut the pipe off using a hacksaw blade with either a plastic cutting blade or a metal cutting blade.

4. Open a bottle of pvc cement or plumber’s adhesive and apply a 1/8-inch layer to the entire bottom of the toilet flange. Set the flange in place over the trimmed pipe and press it down all the way to the floor.

5. Insert the provided stainless steel or brass screws through each of the screw holes in the top of the flange and tighten them fully using a screwdriver.

6. Proceed with installing the toilet and connecting the water supply.

References

• This Old House: How to Install a Toilet
• Fine Homebuilding: How to Install a Toilet