Build Local

 Encouraging the use of sustainable materials from as close as possible.

 Use Local materials, try:

• Cob Houses

• Straw bale houses

• Sand bag houses

There is an acute shortage of affordable housing in Southern Africa.

Earthbuilding offers a way to construct comfortable, durable housing using local labour and resources. Depending on the soil type, this could take the form of Cob Building, Mud Bricks, Rammed Earth, Straw Bales or Sand Bags.

While the labour costs of Earth Building are high, there is the potential for people to be trained in building their own home. The material costs are definitely lower and have far fewer environmental costs than conventional cement based construction.

   The Earth Bag building system

• 80 percent reduction in cement use, saving 5 tonnes of CO2 emissions in this aspect alone

• Walls are 9 times more insulating than concrete blocks (380mm earthbag wall has equivalent insulation level to a 1.8 meter thick block wall) – warm in winter and cool in summer

• Condensation - mould and resultant respiratory problems are not an issue

• Cost effective, rapid construction times

• Structurally sound and literally bullet proof!

• High fire resistance

• Excellent acoustic properties

• Versatile wall materials and finishes possible – sand or clay-earth, and natural paints

• Humidity control when using natural earth materials and finishes

• Wonderful aesthetics when natural earth materials utilised

• Reduction in water usage in construction

• Minimised injury risk on site

• Minimal transport costs with local material use

• Minimised wastage and use of landfills

• Minimised site security issues

• Simple to understand with construction by unskilled communities

• Building costs are more community and less corporate orientated

• Temporary housing easily constructed with all materials reusable

Straw Bale House under construction

  Cob House method

This method  involves mixing straw, sand, clay and water and stomping it with your feet to get the right mixture. This is then shaped into a long roll and little ‘cobs’ (round loaf shaped bricks) are cut and applied by kneading them into the walls – giving the walls a life of their own and allowing the house to breathe in such a way that the house remains cool in summer and warm in winter. A sizeable cob house, if you know what you’re doing, can be built for next to nothing using earth from your site, salvaged windows and doors and a little imagination for your roof.

See Urban Sprout's article on Simric Yarrow's house in Cape Town and his Blog about the entire process

Building Straw Bale Houses

 

Some examples of Cob Houses