Basement Floor Drain Replacement


The basement floor drain is a network of pipes connecting the basement and the sewer system. The visible part of this network of pipes is usually a metal or plastic grate even with the basement floor. The function of the grate is to prevent large sized solid matter from getting into the piping making up the drain. Below the grate is a plastic bowl, and below that is a U shaped P-trap.

How does the Basement Floor Drain Work?

In basement floor drains utilizing a P-trap, the bowl beneath the grate has two outlets. The first is directly below the grate while the second is on the wall of the bowl. The first outlet leads to the P trap and is the main route through which water flows. The second outlet is the bypass route used in unclogging pipes extending beyond the basement floor drain. A removable plug known a clean-out plug closes the bypass outlet.

The function of both the P trap and the clean-out plug is to prevent foul smelling harmful sewer gas, originating in the sewer, from getting into the basement. The P trap is a U shaped pipe, which always retains a small amount of water as a result of the U shape. This water in the trap is what prevents the sewer gas from getting into the basement from the sewer.

The steps below describe the procedure for replacing a basement floor drain.

  1. The plumber will need to determine the direction in which pipes are laid from the drain to the sewer line.
  2. On the basement floor he will mark two parallel guidelines in the direction of the underlying pipes up-to the basement wall. The distance between guidelines is 5 inches.
  3. Using an iron chisel and hammer, he will then remove the concrete above the pipes and 3 inches around the drain
  4. Once all the surrounding concrete is removed, the drain and immediate piping should be visible. It should be possible to disconnect the P trap drain from the rest of the piping. With at least 2 meters of pipe exposed, bending the piping without damaging it should be possible.
  5. Once the worn out P trap floor drain is out, it can be replaced with the new drain. Make sure he uses pipe-sealing tape in the joint between the new drain and the rest of the piping. Sealing tar can be used to further reinforce the joint to avoid leaks. Following the right procedure is very important in order to avoid leaks.
  6. Next he will return the drain and piping into the space in the concrete and fill the space with freshly prepared concrete. Fast drying cement is used to allow fast drying of the concrete and usually takes not more than 10 hours.Basement floor drain replacement can be time consuming. If the entire exercise is not done well, complications such as leaks can arise later on. Therefore, It is recommended to seek professional help to make sure the replacement is completely successful.