These 2x4 knee walls, have PT plates and foam gaskets. They are supporting 2x10 floor joists. This home is new construction. It appears that these knee walls supporting joists are built on slab. I could not define the difference between the slab and footings under these wall. Typically, I can see the joint between the footing and slab. My concern is obviously if these knee walls are built on 5-6 inch slab they may be lacking footings. What do you think and what is your recommendation regarding writing this up? It obviously has been passed by authority having jurisdiction. Thanks!