Additions can go either way, and each has its complications. If we go up, then we need to ensure the existing walls and foundation can support the additional weight. If we go out, we'll need to clear the land, excavate and pour a foundation. There are oh so many of other details to figure out and plan for with an addition, which could easily take six months from concept to permitting, and then another six months or so to build and finish. Here's the process to put an additional on your home: