Craving more usable living space? According to Board & Vellum, a Seattle design firm, a huge addition to your home isn’t your only option. For a single-story home, adding on a second floor is enough to maximize the structure’s square footage, giving a family some much-needed breathing room. Consider some great space-saving solutions such as installing built-ins and turning a window seat into a reading nook. Other economical ways to increase living space include finishing the basement or transforming an attic into loft space.