Last week I got my first ever customizable house. I'm planning on remodeling it, including replotting it from a 15x15 2-story to a 15x15 3-story (or bigger if it fits). An image is in my head of a cantilevered design. Imagine a 12x12 walled area in back, with a 3-wide patio along the 2 facing sides. The cantilevering would occur with the second story being the full 15x15 area. I.e, the second story overhangs the patio area. Is this doable?