A Rammed Earth House in the Navajo Nation
Bridgette Meinhold at Inhabitat is reporting that a bunch of students from the University of Denver have just completed this house on Navajo nation land. Other than this post-modern cement siding window wall, the remaining walls were built with rammed earth.
The earth came almost entirely from local clay, both to make the compressed bricks and to form the rammed earth walls that make up the South and East walls.
The two big advantages of rammed earth are its economy and energy-efficiency. It is freely available anywhere there is earth, so you can build with local vernacular material. Some earth is better than others, but it can be amended with a little cement.
The kids built it all in under 6 months – they started construction on it in September, with the planning begun in May last year.
Rammed earth building doesn’t take skilled labor if building by hand makes sense, and it is easily built with some help from machines in places where labor is expensive.
The energy-efficiency of rammed earth comes from the way it creates “thermal mass” – a slow form of heat storage for the warmth of the sun so that the sun soaks into the walls all afternoon, and releases the warmth through the cold evenings.
This makes it ideal for desert climates like Colorado that have extremes of heat by day and cold at night.
Homes in the Navajo nation are completely off the grid, so this natural energy conservation technology, combined with passive solar design, is key to creating comfortable places.
Because rammed earth walls can last virtually forever – part of the Great Wall of China is built this way – its economy extends far into the future. That makes it about the greenest way you can build.