How to Hook Up the Toilet in a Cellar

Cut into the concrete with a jackhammer or concrete cutting saw, and create a 4-inch-wide path from the toilet to the main drain line. Also cut out a hole at the point of installation for the toilet flange. Place the toilet flange on the concrete and trace around it with a marker to get an idea of how large of a hole you will need.

Cut into the drainpipe where the new toilet drain pipe will connect with it using a pipe saw. Install a T-fitting here to connect both sides of the freshly cut main drainpipe. Orient to the open end of the fitting so you can connect the new toilet drain line to it.

Connect 3-inch PVC drain piping to the T-fitting and run it to the toilet. Connect the toilet flange to the toilet drain line. Once the flange and drainpipe are connected and everything fits properly, take everything apart and assemble it again using PVC adhesive.

Cover the flange and drainpipe with gravel. Pour fresh cement over the drainpipe and around the flange. Use a flat tamp tool to smooth over the cement and make it flush with the existing floor.

Mount the toilet on the flange after the cement has had at least 24 hours to dry and cure. Tighten the wing nuts on the flange mounting bolts with a wrench to secure the toilet in place.