# Distance of raft foundation outwards

Can you tell me (for USA) which code (or standard or guide) and in it where exactly I can see the distance required for the raft foundation, as far as how much it should extend horizontally beyond the outermost columns of the building? (In other words, how much larger it should be (as a minimum or a specified ratio etc...) than the building footprint as defined by the outer columns) I checked ACI 318, IBC, NEHRP document and cannot see it. Unless I missed it. Please help.