There is no need to remove the bearing wall footing unless it somehow is too high. It’s a common practice for the basement slab to be poured so it rests directly on top of the footings.

ACI 117 then provides section 3.5—Deviation from cross-sectional dimension of foundation, in which the effective width of the footing or foundation is given a tolerance. Those are: Formed ...

When a foundation is poured, its footing—a wide flat base made from concrete and reinforced steel, designed to support the walls—is poured first, and then the walls are poured on top after ...

If there is a basement, it may be surrounded by a ledge of dirt that helps hold the walls in place. If people still lived in the houses as their ancestors did, such construction wouldn’t matter.

How to Prevent Frost Heave Around Your Foundation "You can minimize this damage by directing the moisture away from the area that would influence footing movement," notes Brown.

Most homes built between 1880 and 1930 were built on inferior footing. These old footings offer foundation walls little support, which then may support often overspanned joists and girders.