One-story House Plans: One-story house plans are just that: single-story house plans that offer one level of heated living space. Generally speaking, one-story house plans are well suited to larger lots, where economy of land space needn't be a top priority. One-story house plans are also very popular with those homeowners who intend to build a house plan that will age gracefully, providing a "life without stairs" as they may find themselves moving just a bit more slowly over time! Smaller one-story house plans carry a financial bonus, too: They are usually very energy-efficient simply because there is less space to heat and cool.