Using sandbags piled up to create a wall is nothing new. For decades or even centuries people have been aware of the good qualities of sandbags for flood protection, for sound insulation or in providing shelter against bullets. But the idea of using sandbags as a construction material for ordinary housing is fairly new. It was developed as a complete building system during the last ten years in Cape Town, when Michael Tremeer and his company Ecobeam Technologies searched for a cheap way to assist South Africa in its endeavour to house millions of homeless residents. The result was the simple idea of building the walls of houses out of sandbags. Contrary to the original intention, more and more wealthy people wanted to build ecological buildings by using sandbags. Today, timber-frame and sandbag homes have found their way into many suburbs across South Africa, as this building process – and the specific design of the materials – is particularly cost-effective
The system has been extensively tested and exceeds all the required building code standards in terms of structural durability, fire ratings, thermal stability, water penetration etc. and thus approved by the NHBRC.
Some of the main advantages of building sandbag houses is the components are cheap, easily available and easily transferable. The use of sandbags in house building reduces CO2 emissions by up to 95-percent compared to standard brick built walls because there is no processing of materials prior to use in the construction. The houses are earthquake safe, fire proof, wind proof, sound proof, water proof, low maintenance, economical to build and the system is user friendly. In addition, sandbags can be up to 40-percent cheaper than brick. It has extremely good thermal properties – cool in summer, warm in winter. When sandbag houses are completed with plastered exterior and interior walls, they will look identical to a house built from conventional materials.
A disadvantage is that its greatest enemy is moisture – thus one needs to adhere to good building practices especially when building in rain prone areas i.e. good foundations, proper sill details, proper roof over-hangs and the use of breathable plasters and paints. It is always best to get good technical assistance from someone who understands these materials when building with them.