Floor Trap or Floor Drain: Which is it?


A floor trap is designed to trap air from the sewerage line to prevent its escape into the house. A floor drain on the other hand is a drainage line that is used to lead water out of your home.

Floor Trap

  • In most cases, the floor trap will be found installed in the drain lines that lead wastewater from the home. The trap is usually u-shaped but can be shaped like a –p or –s. This design makes it easy in trapping the air from being led back into the house.
  • As sewage and dirty water go down the pipes some sludge and other sediment will collect in the pipes, and along the sides of the pipes. The floor trap is necessary in ensuring the home does not smell bad due to the bad smell of rotting effluents in the sewerage system. The trap will hold some water, keeping the odors out. If the trap is missing or dry it will not work correctly and you will smell sewage odors in your house.
  • If you have an older home, you may not have traps. If this case you will want to have some installed. It’s very easy to determine if your home has floor traps. Pour 2 or more gallons of water, quickly, down the drain. If you look in and see some water in the pipe, you do have traps. Check back in an hour or so, you should still have a bit of water in the pipes. If the water just goes right down the drain, you don’t have traps, or the trap is located in a different place. If you notice an odor after a couple more hours you do not have a trap.

Floor Drains 

A floor drain is usually found in a basement, or laundry area. This will allow any overflow to have a place to drain, rather than flood your room. This is simply because the floor drain will lead all the water that may be pouring in your home out to the nearby waterways. The best time to install this is during construction. To add one later will involve removing large parts of the floor to connect the drain to the sewage system.

If you have a good floor drain and trap system, you should not have any sewage odors backing up into your home.