What is the best way to build a low-cost home that doesn't harm the planet? Most materials such as concrete and steel are highly processed and transported long distances, making them unaffordable to millions who are in need of housing. These high-tech materials also cause a great deal of harm to the environment. The answer is to utilize locally available, low-impact natural building materials such as earth, stone, straw and small diameter wood. This article explores several methods of using earth and sustainably harvested wood to cut housing costs to rock-bottom prices. And because the techniques are user-friendly, they are ideal for do-it-yourselfers.

Earthbag building: Like other earth building methods, earthbag building is simple to learn and extremely low cost. It has evolved from the military's use of building durable, blast and bullet resistant structures with sandbags for 100 years. Modern-day builders are using the same basic process of filling and stacking bags to build beautiful houses, offices, shops, schools and orphanages. Earthbag buildings are resistant to mold, fire, hurricanes, tornadoes, earthquakes, floods, insects and rodents.

Since the main building material is earth, which is often free or very low cost if delivered, structures can be built literally dirt-cheap. No expensive equipment is needed. Most people already have the basic tools around their home - shovels, buckets, garden hose and ladder. The building process is so simple that unskilled workers can learn each step of construction just by watching for a minute. Earthbag building is extremely adaptable and can be used to build almost any shape imaginable, including domes, vaults, roundhouses, or more typical square or rectangular designs.

Small diameter wood: U.S. forests are currently overcrowded and prone to forest fires. Millions of acres are destroyed each year to fires and disease. Gleaning small trees from the forest in a sustainable manner actually improves the health of the forest and reduces forest fires. With an inexpensive firewood permit (about $20), anyone can obtain wood for building their home. Most of this wood usually goes up the chimney to heat homes, but it is much more valuable when turned into useful products with a long life. All the wood for a house can be obtained this way at much lower cost than buying dimension lumber from a building supply center.

One option is peeling the bark off and using them in the round for pole frames. Wood in the round is much stronger than sawn lumber and requires less processing. With a portable mill or chainsaw attachment, do-it-yourselfers can also mill their own wood for beams, joists, studs, trusses, purlins, window and door frames, trim, cabinets and furniture. Where I live, builders are culling standing dead trees (sound wood) from the forest so as to avoid the time and effort of seasoning the wood. In addition, using sustainably harvested wood as described here is more aesthetically pleasing than conventional stud walls covered with sheetrock. The beauty of the wood is left exposed, honoring the tree from which it came.

Tamped earth floors: Traditional poured earth floors can last for many centuries, thereby saving a small fortune on wood floor framing and replacement of carpet and linoleum every 15 years. Earth floors look like leather once finished and are extremely beautiful. (They're being used in trendy, custom homes.) However, poured earth floors take a long time to dry, making them impractical in all but hot, dry climates.

Tamped earth floors use less water and dry much faster. These floors can typically be walked on one or two days after installing. The building process involves screening road base or other appropriate soil through 3/8" mesh. This mix is spread out in 2" layers and tamped level. The process is repeated until the desired height is reached. Material for the top coat is screened again through 1/8" mesh. The top coat mixture is hand-troweled and burnished, using just enough water to bond well. After the floor has thoroughly dried, seal with several coats of linseed oil thinned with turpentine.

Earthen plaster: The most beautiful wall finish I've ever seen is earth plaster. If you've never seen earth plaster before, you may think of dreary brown walls. Do an Internet search for "earth plaster" and you'll see the amazing results. Because there are many kinds of clay, there's no limit to the range of colors, textures and special effects. One popular method uses mica in the plaster to create sparkling, brilliant walls.

Earthen plaster is the probably the most user-friendly wall finish. In many cultures women, children and the elderly have done the plaster work for centuries using just hands and basic tools. The key to durable earthen plaster is wide roof overhangs of about 36 inches. Keep rain and snow off the walls and it will last a long time, requiring only minor touchup.

These are just a few ideas to get you started thinking about using natural building materials. Thanks to the Internet, now it's very easy to learn about these and other low-cost building methods. Additional articles on the above topics are available for free on the author's websites.