One of the most staggering claims of the Earthships is that they can withstand temperatures that range from 30 below freezing to 40 degrees above freezing and yet maintain a steady 19 degrees or so without any heating.

This is achieved by a combination of thermal mass in the form of thick earth filled tyre walls and correct alignment with the winter sun angle.

I got up today to find a sprinkling of snow on the foothills of the mountains and ws suprised how chilly the outside was. I had previously seen a thermometer inside the house always showing 18-21 degrees and decided to take it outside. It was 10 degrees cooler. The Earthships maintain a steady temperature from the thermal mass stored in the Earth walls. It really is quite amazing