PVC (Polyvinyl chloride) is a strong rigid white or gray plastic used in the installation of sewer and vent lines, with the section using primer, cement and couplings to join together. When a new sewer line needs to splice into an existing line, the existing line must be cut and a Tee coupling installed. This coupling has three inlets, two to connect to the existing line and one to attach to the new sewer line.
Mark the existing sewer line in the place where the new sewer line will be attached. Make a second mark on the pipe two inches down from the first mark.
Saw through the pipe at both marks, making the cuts straight, perpendicular to the pipe and parallel with each other -- use a circular saw or handsaw. Remove the two inch section of pipe. Scrape off all burrs from the sawn pipe ends with a utility knife and remove any small plastic fragments with 80-grit sandpaper.
Brush PVC primer around the outside of both sawn pipe ends -- brush to a width of 3/4 inch. Also, prime the inside ends of the PVC tee coupling opposite each other -- do not prime the tee's leg. Apply PVC cement to all four primed areas.
Squeeze the tee coupling between the sawn sewer pipe ends, making sure the pipe ends enter fully into the tee's inlets. Position the tee's leg up and in the direction of the water fixture it will eventually connect to. Hold the tee to the pipe ends for 10 seconds while the cement sets.