The thick walls act as a thermal mass, gently absorbing heat during the day and radiating it at night. Corner fireplaces provide heat to the rooms throughout the cold. Winter rains melt some of the moisture from the roof, which then runs down into the wall crevices to be absorbed by the dry earth beneath it. Adobe is a durable material that can stand up to harsh conditions. When building a house from scratch, you would first need to select a site for the foundation and then choose an appropriate shape for it. You could then start gathering materials like dirt, rocks, and seeds and follow any one of several simple methods to get them ready for use as adobe. For example, you could make a pile of the ingredients and hit them with a shovel or hoe until they're all mixed together well. There are also pre-made mixes available for different price points. Once your base is ready, you can add more to it like grasses for insulation or plants for color. This method is commonly used for garden beds because it's easy and convenient, but it can be done with dirt from anywhere else on Earth if you have the right mix. Desert houses need to withstand high temperatures and intense winds so they usually have very thick walls. Thick walls mean more mass, which means better protection from wind and rain.