Earth as building material

Earth has been a common building material through Chinese history. During the Neolithic period, people lived in caves or built their homes above ground using wattle and daub technique. More substantial, load-bearing walls can also be made of pounded earth, a technique that also has a long history in China. Here is an example of how these houses are made.

A wooden frame is constructed to hold the earth, and then the dirt is pounded into place.

In terms of actual construction, what might be some of the advantages of building with earth?

Using a log frame to build an earthen wall, Xian area, Shaanxi Province

SOURCE: Photograph courtesy of Ronald G. Knapp, 1983, Xian area, Shaanxi Province

SOME THOUGHTS: Building with earth involves technology that is straightforward enough to be applied by many people. Construction can be done cooperatively, without the need for the presence of an expert. In addition, earth is available everywhere, and so is an affordable building material for people with lower incomes.

After the earth dries, the wooden frame is removed. The mold is being removed here, revealing an earthen wall that is free-standing. The impressions left by the mold can hold plaster after the wall dries.

Not all earthen walls are plastered.

In what regions might plastered walls be preferred?

ANSWER: In the south, plaster protects earthen walls from rain, and also radiates the sun's heat away from a building.

How do you think the wall is given stability?

ANSWER: Without a rigid frame such as wood to hold it up, the wall must have a firm base; note how wide the bottom of the wall is compared to the top.

Extra materials could also be added to strengthen the composition of the earth, such as straw, paper, oils, lime, shells, or sand, depending the region.

What might be some advantages to living inside a building with earthen walls?

Building an earthen wall, Xi'an area, Shaanxi Province

SOURCE: Photograph courtesy of Ronald G. Knapp, 1983, Xi'an area, Shaanxi Province

Earth is also used to make bricks. There are several ways that bricks are made. In general, dirt or clay can be formed by frames and dried. Sometimes the earth is fired to make the bricks harder, but other times the earth is just left to dry in the sun.

In Southern China, bricks can also be cut directly from a field after harvest and left to dry in the sun before they are fired. Here are some examples of this process from Guangxi province.

SOURCE: Photograph courtesy of Ronald G. Knapp, 1984, Yangshuo area, Guangxi Province

After the earth is smoothed into place, the bamboo handles are used to lift up and move the mold.

SOURCE: Photograph courtesy of Ronald G. Knapp, 1984, Yangshuo area, Guangxi Province