This underground dwelling is a 15,000 square foot single residence with unfinished natural sandstone walls. Not only is this a wonderful example of a unique residence, it also is a perfect example of energy-efficient architecture. Because of the nature of it's location within a cave the interior maintains the perfect temperature and living conditions thanks to Geothermal heating and smart passive design... so in short it has no need for a furnace or air conditioning.
The naturally insulating properties of the site’s sandstone walls keeps the climate inside comfortable throughout the year. The cave consists of three chambers, and the Sleepers decided to leave many of the walls in their unfinished natural state, which adds to the home’s charm. The walls do shed sand, however, so the family has built interior roofs and placed coverings over areas that need to stay sand-free.
Because of the housing crises, the Sleepers unfortunately had to foreclose on this unique home and posted it on Ebay with a minimum bid of $300,000....