How to Replace Drain Lines in Concrete

Turn off the water and plug the drain with a rubber stopper in the area where you plan to work. Determine the location of the drain line you need to replace using building schematics or by following the path of your drain lines until they enter the concrete.

Cut a rough square at least 1/4-inch deep into the concrete in the area where you expect to find the drain line using a masonry saw. Use long strokes of the saw to create straight lines.

Break up the top layer of concrete with a demolition hammer. Place the hammer's tip against the concrete in one corner of your square before switching it on. Work your way across the square before breaking up the lower layers of concrete until you reach the drain line.

Stop hammering long enough to remove concrete chunks at regular intervals as you work. Enlarge the hole if necessary to reach the drain line you plan to replace.

Clear away all broken concrete from the drain line so that you have clear access to it. Place a reciprocating saw blade against the pipe and switch the saw on. Apply gentle pressure and allow the saw to make a straight cut through the pipe.

Make a second cut at the other end of the drain line section you want to remove. Lift out the pipe and measure its length with a tape measure.

Cut a piece of PVC pipe with the same diameter to the same length as the pipe section you removed. Place the rubber sleeves that come with the mechanical joint fittings over the ends of the PVC pipe and lower it into the gap left by the section you removed.

Fit the rubber sleeves over the open ends of the remaining drain line. Attach the mechanical joint fittings' metal sleeves and clamps according to the installation instructions that come with the fittings. Pull up on the PVC pipe section gently to ensure that it's firmly in place.

Run water through the drain line to test the mechanical joint fittings. Run your hand around the fittings to check for any leaks. Reinstall the joint fittings if necessary.

Prepare enough concrete to fill the hole you created to access the drain line by adding water to concrete mix in a wheelbarrow; stir it with a hoe until it's fully mixed and the right consistency. Fill the hole by applying wet concrete with a trowel, laying it directly on and around the PVC pipe. Smooth out the top layer to fill in the entire surface once the hole is full.