For centuries, clay and the composites of clay have been a building material of incomparable usefulness and attractiveness. And still today clay has proven itself with excellent properties. From both environmental and economic perspectives, clay is still a valuable, healthy and efficient construction material.
Traditionally, bricks were hand pressed, either sun or kiln dried. Sun-dried earth bricks were produced from the natural sun and air drying process.
IAST developed high compression blocks using coastal clay, these compressed blocks were found to be equal in strength to the concrete blocks currently used in the construction industry at approximately 1/6 of the cost.
Tests and laboratory analyses were done to determine the most appropriate soil for making the compressed clay blocks.
Clay from a predetermined extraction pit was air dried and crushed to smaller particles. The soil was then sieved to remove debris and produce uniformity.
Batches of soil were weighed and the correct proportions of stabilizers, sand and water were added and mixed. Blended into a homogeneous mixture, it was placed into the mechanized block making machine where it was compressed, extruded and placed on the ground to be air dried.
The extruded blocks were stockpiled and covered and cured under a shed for at few weeks and then uncovered and dried for a number of days. The compressed earth blocks were then ready to be used.
The blocks are suitable for the construction of domestic dwellings, since it was tested for compressive strength and compared evenly with cement blocks.
IAST subsequently constructed at 20ft x 20ft Eco-house on the south western of its compound using the compressed earth blocks to build the external and internal walls.
The Environmentally friendly house also has a thatched roof constructed with trouli leaves and windows, doors and furniture made of bamboo materials. The house is power by a solar system.