Natural Building "Natural building" is an umbrella term than connotes any sort of building that is accomplished with the use of natural materials primarily, as opposed to the use of man- made or industrial materials.

2 Points to Remember

Think Small Small can be beautiful and cozy. The trend lately has been toward huge mansion-style houses. Large houses generally use a tremendous amount of energy to heat and cool. Also, the larger the house, the more materials go into its construction; materials which may have their own environmental consequences. A home should be just the right size for its occupants and their activities.

USE LOCAL MATERIALS In almost all localities, nature has provided us with some wonderful materials to build with. Because these materials require little processing or transporting, the environmental and economic costs are low.

BUILDING STYLES

Adobe Adobe is one of the oldest building materials in use. It is basically just dirt that has been moistened with water, sometimes with chopped straw or other fibers added for strength, and then allowed to dry in the desired shape.

Commonly adobe is shaped into uniform blocks that can be stacked like bricks to form walls, but it can also be simply piled up over time to create a structure.

Cob Cob is a very old method of building with earth and straw or other fibers. It is quite similar to adobe in that the basic mix of clay and sand is the same, but it usually has a higher percentage of long straw fibers mixed in.

Instead of creating uniform blocks to build with, cob is normally applied by hand in large gobs (or cobs) which can be tossed from one person to another during the building process.

Rammed Earth Ramming earth to create walls is at least as old as the Great Wall of China. It is really quite similar to adobe and cob techniques, in that the soil is mostly clay and sand.

The difference is that the material is compressed or tamped into place, usually with forms that create very flat vertical surfaces.

Earthbag Building with earthbags (sometimes called sandbags) is both old and new. Sandbags have long been used, particularly by the military for creating strong, protective barriers, or for flood control.

The same reasons that make them useful for these applications carry over to creating housing: the walls are massive and substantial, they resist all kinds of severe weather (or even bullets and bombs), and they can be erected simply and quickly with readily available components.

Strawbale Building with bales of straw has become almost mainstream in some parts of the country, especially in the Southwestern United States. Many localities have specific codes for strawbale construction, and some banks are willing to lend on this technique.

Straw is a renewable resource that acts as excellent insulation and is fairly easy to build with. Care must be taken to assure that the straw is kept dry, or it will eventually rot. Other possible concerns with strawbale walls are infestation of rodents or insects.

Lightweight Concrete Lightweight concrete, weighing from 35 to 115 pound per cubic foot, has been used in the United States for more than 50 years. The compressive strength is not as great as ordinary concrete, but it weathers just as well.

Among its advantages are less need for structural steel reinforcement, smaller foundation requirements, better fire resistance and most importantly, the fact that it can serve as an insulation material!

Earthships The primary retaining walls are constructed with used tires, filled with earth and stacked up like bricks. The interior surface of the tires is then plastered with adobe or cement so the tires don't normally show.

Mike Reynolds (creator) has also pioneered the use of empty aluminum cans mortared into lightweight, curvable walls. Earthships often employ many ecological concepts, such as water catchment from the roof, reuse of greywater, composting toilets, indoor gardening, etc.

Cordwood Cordwood construction utilizes short, round pieces of wood, similar to what would normally be considered firewood. For this reason this method of building can be very resource efficient, since it makes use of wood that might not have much other value.

Cordwood building can also create a wall that has both properties of insulation and thermal mass. The mass comes from the masonry mortar that is used to cement the logs together, and the insulation comes from the wood itself and the central cavity between the inside and out- side mortars.