Building Using Cob
Cob is an ancient earth building technique which uses a combination of earth, straw, sand and water. These ingredients can be mixed together by hand, using tarps, or by machinery. The mix is formed into lumps or 'cobs' which are pressed together to form the walls of a building, rather like building a giant clay pot...
When left to dry the cob sets to become extremely hard and durable, although in wet areas like Britain cob walls need protection from driving rain which will eventually erode them. There are thousands of cob houses still inhabited in England today mainly in Devon and Cornwall. It is estimated that 30% of the world's population live in earthen homes.
A simple technique to learn, safe, non toxic and lots of fun to build with, you can use cob to create almost any structure - from the simple to the fantastic. Cob structures can be finished using different mixes of the same materials, to produce beautiful paints, plasters, floors, furniture and sculptural features.
Cob building uses the world's most abundant and sustainable building materials, has very low embodied energy, and its cost is minimal. Virtually all the materials used in the cob building process are bio degradable or can be recycled, making it one of the most environmentally friendly ways of building.
Today there are many cultures who still recognise the advantages of building with earth, and draw upon the natural landscape to create their own architecture which is both practical and sustainable. Architecture which reflects the rich variety of human culture, imagination and personal identity.
Sustainable Building Technologies:
A Glossary of Terms
Why Build With Earth?
Save A third of the world's land mass is suitable for building with earth which means the majority of the building material can be found on or near the site. This reduces the cost of transporting and processing the bulk of materials used in construction. It also saves exploiting new resources by incorporating recycled materials into the design. Cob is load bearing and needs no framework. A house made of earth typically uses 60% less lumber than a stud frame building.
Reduce Cob building reduces the need for specialist skilled labour and expensive equipment. The construction techniques we use are easy to learn and reduces the amount of money required to build structures. Typically in America a house might cost $200,000, but with these techniques people have built their own homes for under half this cost. The flexibility and fluidity of cob building allows for curvilinear shapes, which encloses space more efficiently and thus reducing the size of building required.
Improve Cob building improves the quality of the environment, the materials used for building, as well as finishes such as paints and plasters are non-toxic and non-polluting.