Drain tile location re residential house

For best result the bottom of the drain (invert) should go at or below the bottom of the footing.

Bottom

Although, lower is probably better since you are moving the water well before it has time to accumulate against the foundation, your location and footing installation may dictate the placement of the foundation drain.

The posters who have already answered that the drain be located at the bottom of the footing must be located in areas where the footings are formed and poured.

There are other areas where the footing is created by digging a trench in the earth. That entire trench is then filled with concrete to create the footing. With this installation, the foundation drain is placed on top of the footing, but below the basement slab level.

The drain is then covered with gravel and a filter membrane.

Shannon Pate

The flow line of the drain tile has to be below the finish floor. The lower, the better to keep the water level down, but finish floor is the determining factor.