Rammed Earth has amazing energy efficient properties, but it has to be used the right way. Rammed earth doesn’t act like insulation material like roofing bats (with lots of tiny air pockets) but it has thermal mass.
It is probably best related to living in a cave.
A well designed rammed earth house will have eaves that enable the sun to hit the wall in winter. The walls will absorb all the suns heat and slowly release that energy over the next 12 hours. This is called thermal lag, which rammed earth has the best rating of any material (far better than concrete or stone), and evens out the fluctuations in day and night temperatures. In summer the walls are shade from the sun, resulting in a comfortable and constant living temperature all year around.
Thermal mass is great for the performance and ongoing running costs of a house. The need for air-conditioners and heating is greatly reduced. The air quality is also much better than any other material as it regulates the humidity and exchanges the air constantly. It also has no toxins or VOC’s.
The design is very important for solar gain and also for reducing construction time and costs. If you would like any advice, we would be happy to help. Please go to our contact page.
Rammed earth also has very low embodied energy. The material is usually source from local sources and the whole construction process has a small carbon footprint and is one of the easiest building product to recycle at the end of the buildings life.