Some advantages to building underground homes include decreased outside maintenance, lower insurance costs, and increased protection from extreme outdoor temperatures, high winds, hailstorms, tornadoes and other natural disasters, according to Energy Saver, a consumer resource by the U.S. Department of Energy. Underground homes also provide increased soundproofing and more energy efficiency than conventional houses.
Underground homes have some disadvantages, such as increased risk of moisture problems and increased building costs, states Energy Saver. Underground homes sometimes cost up to 20 percent more to build than conventional homes, and the mortgage process may be more involved. Underground home owners may also have difficulty selling the home if they choose to move.
Before deciding to build an underground home, individuals should consider the location's climate, topography and soil. Underground homes are most cost-effective in dry climates with frequent temperature extremes, such as the northern Great Plains or the Rocky Mountains, explains Energy Saver. The building site's topography also determines how much excavating is necessary to surround the home with earth. Building underground homes on sites with gravel or sand is preferable, because these soils drain water easily and provide adequate support for the home.
When building an underground home, it is important to consider appropriate waterproofing to reduce the risk of water damage, notes Energy Saver. Controlling indoor humidity levels and providing adequate ventilation are other important considerations.