The Eco-Friendly Building Method You've Never Heard Of

by Steve Graham, Networx

Cob construction is like shaping a house with artists’ clay but never baking it. Cob (which borrows an Old English word for mound and has nothing to do with corn) is a mass of straw, clay, sand, and water. In a gradually reviving form of construction, it is hand-sculpted into buildings while the mixture is still wet.

Cob construction may be the world’s most environmentally friendly building process. There are no additives or chemicals. No energy is consumed in heating or forming the material, and no heavy machinery is required. In the right areas, the basic building materials all can be obtained locally.

Cob was used for many years in Europe, and is still widely used in Africa. Many European earth structures are still standing despite centuries of rain and harsh winters.

It is closely related to adobe, a popular building style in the Southwestern United States. The main difference is bricks. Adobe uses sun-dried earth bricks connected with mud mortar. Cob construction is a simpler concept, but takes detailed planning. Here are the first steps of cob construction.

Choosing a Site

The most important factor is drainage. Cob will break down if it is submerged. Make sure that even a 1,000-year flood won’t saturate your cob walls.

Instead, build on a hill to ensure good drainage. Cob works well on sloped properties that complicate standard frame construction. Also look for full sun exposure in the winter, and land with available clay soils, if possible.

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Disclaimer: The views expressed above are solely those of the author and may not reflect those of
Care2, Inc., its employees or advertisers.

Danielle H.

8:24AM PDT on May 11, 2011

THANK YOU

send a green star

DobieMax W.

8:08AM PDT on May 11, 2011

Noted

Susan W.

12:48PM PST on Feb 21, 2011

interesting

Eternal G.

1:22PM PST on Dec 10, 2010

I've certainly not only heard of it but also am using it for building my backyard oven!

Emily C.

7:23AM PST on Nov 23, 2010

This is amazing.

J. H.

3:31PM PST on Nov 16, 2010

like living in a sand castle...it would make me nervous!

Judy H.

6:47AM PST on Nov 16, 2010

A similar technique is called rammed earth, and I've been fascinated by it all for years. However, I've found out that this type of construction doesn't work in all climates, especially in areas of high humidity.

Past Member .

2:31PM PST on Nov 15, 2010

Very interesting! Thank you.

Miranti B.

7:54AM PST on Nov 15, 2010

wooow.....so interesting ^^

Sheri P.

11:56AM PST on Nov 14, 2010

You're right, I've never heard of it before...interesting!