by Robert Douglas McDonald, CSS CSI

We currently think green architecture is the now of the future: sustainable, renewable, organic and environmentally friendly. Yet one form of architecture that is inherently green and has been around for millenniums – since the beginnings of time, is adobe. History records ancient structures of mud brick construction in Africa, Asia, the Americas and around the world. Over one half the world’s population are still living in this form of construction. There are 59,000 adobe dwellings in New Mexico alone which represents one third of those in USA.

Adobe construction is solar heated, cool in the daytime and warm at night, is made of materials found at the site (no transportation costs), is made of units baked by solar energy (but may also be baked in small onsite ovens), can have supporting and roof coverings of local growing materials, and has survived for centuries.

Modern adobe can be stabilized by a small addition of lime, or Portland cement, or asphalt. Modern adobe constructions can be vertically reinforced with bamboo. Modern adobes can be made to be resistant to seismic forces by the addition of horizontal bond beams tying the opposing walls together.

Adobe does not bond well to steel so vertical reinforcing can be made with bamboo. This has been done in China and Thailand. In India, after many earthquakes, it was found that the critical point of masonry walls was at the top of the wall to be reinforced to resist overturning. This means a change of materials – reinforced concrete bond beams. These can be made with soil-cement concrete or Portland cement concrete. In either case the aggregate mixed in the same way.

Other sustainable features include:

-Bamboo is the fastest growing grass material – some species capable of growing a meter a day. Bamboo can be planted by seed, stem, and rhizomes. It is very strong and renewable. Some structures in China and East Asia are nearly or entirely made of bamboo.

Desert and high desert architecture in Egypt, Iran and Arabia have used adobe structures that have been made with natural ventilation by the use of high ceilings, high vertical stair towers that allow for upward movement of warm air and can be cooled by the addition of wind powered ventilator stacks that draw warm air out of high ceilings.

Earth-built homes by the high thermal mass (walls 12 inches thick) can render more substantially, more energy efficiency than stick built homes.

Certainly, adobe homes are visually favorable to the environment- perhaps one of the reasons Frank Lloyd Wright was endeared to the Southwest by the example of the Native American traditions of adobe villages and structures. FLW also stressed the need to be site friendly. The books by Carr and Witynski, and Seth greatly illustrate the beauty of these homes, interiors and details.

Endless variations of earth construction has been initiated and recorded including; soil cement, stabilized adobe bricks, pressed adobe bricks, rammed earth, cast earth, water-resistant adobe bricks and other materials. The difference between adobe bricks and our brick masonry units of today is the high temperature that masonry bricks of today are fired at.

But fully stabilized adobe units are approaching concrete block in density. Traditionally, adobe was covered with mud periodically, then lime stucco and now stabilized stucco. Adobe must be protected from moisture penetration and placed on waterproof foundations.