6. Rammed Earth
For many people, wood is neither affordable nor available, so resourceful builders use what they have: the ground beneath their feet. To build a rammed earth home, a mixture of soils is packed down into a temporary wall form that shapes the mixture. The form is usually wooden, and it must be strong enough to withstand the compression of the ramming. Ramming can either be done by hand or by machine, and once it's completed, the forms can be removed, leaving an earthen wall about 18 inches to 24 inches (46 cm to 61 cm) thick.
Rammed earth walls require a cross-grade of soils, but too much clay will cause the walls to crack. Walls can be plastered with stucco or left bare; bare walls usually are internally stabilized with a small percentage of cement. When properly constructed, rammed earth walls are extremely durable, holding up in bad weather, as parts of the Great Wall of China can attest. They also provide energy savings because of their thermal mass.
One of the primary challenges of building a home with natural materials is getting it built in the first place. Natural materials are rarely, if ever, mentioned in building codes, and building officials may be unfamiliar with these methods of construction. Banks are hesitant to finance alternative methods, and it can be difficult to prove safety standards to insurers. While many of the materials lend themselves to do-it-yourself construction, it can be difficult to find contractors if backup or consultation is needed.
If you decide to pursue natural building, it's important to present strong research to officials. Sit down with building officials early and often and show off the advantages of natural building. Know where these materials work best, and find data on structural safety. Have consultants and specialists evaluate your plans. While gaining acceptance for an alternative building method might be difficult, it will pave the way for increased natural building in the future |
If you prefer your earth neatly bagged rather than rammed, read on.
