What you do have going for you is that one of these house is pretty compact, by way of exterior floor ratio to inside usable house, much like the 2-story method above. However, giá xây nhà tại Cần Thơ don't kid your self: it'll always be inexpensive to build a standard frame wall above the ground (See probably the most economical approach above) than it will likely be to excavate an enormous gap in the ground and to kind and pour a steel-strengthened 8″ to 12″ thick concrete wall that you then must waterproof from the exterior, then insulate and body out on the inside. Modular housing must conform to the home site's state, native and regional building codes -- which go above and past HUD Code restrictions.