Attaching Shower Flanges to Concrete

Fit the shower flange into the drainpipe in the floor. Push the flange all the way down until its ring is flush against the floor. Mark the positions of the three flange-mounting holes on the floor with a pencil. Remove the flange from the drainpipe.

Drill holes at each mark in the floor, using a masonry bit of the size designated on the plastic anchor package. The holes should be at least 1 inch deep.

Vacuum each hole to remove the concrete dust residue from the drilling process. Insert a plastic anchor into each hole, and use a hammer to tap them flush with the floor surface.

Apply an 1/8-inch bead of silicone caulk to the bottom of the shower flange ring, using a caulk gun. Insert the flange into the drain pipe, aligning the mounting holes with the plastic anchors. Press down on the flange ring to ensure good contact for the silicone caulk.

Thread retaining screws through the flange ring and into the plastic anchors. Tighten the screws with a Phillips screwdriver.