What do you say about a garage converted to a living space and there is no footing where the garage door used to be? Presumably there is a header there and the new wall doesn’t support a load. However, the code says there shall be a footing at “all exterior walls”.
R403.1 General. All exterior walls shall be supported on continuous
solid or fully grouted masonry or concrete footings,
crushed stone footings, wood foundations, or other approved
structural systems which shall be of sufficient design to accommodate
all loads according to Section R301 and to transmit the
resulting loads to the soil within the limitations as determined
from the character of the soil. Footings shall be supported on
undisturbed natural soils or engineered fill. Concrete footing
shall be designed and constructed in accordance with the provisions
of Section R403 or in accordance with ACI 332."