Interlocking Stablished Soil Bricks (ISSBs) come from a broader family group of earth bricks that are called Compressed Earth Bricks (or Blocks) or CEBs. The common feature of these bricks is that they are made from a soil mix, that is compacted and then dried/cured using the sun. Dry Stack bricks, which are already in popular use in Africa, are made from compressed earth but do not interlock.
The way that ISSBs differ from the broader CEB group is the interlocking capability of the bricks. ISSBs interlock together to form a tighter bond/link which helps in load transfer, resulting in better resistance to exposure to extreme lateral forces (e.g. hurricane wind forces, earth quakes).
Self locking is achieved using a shear-key and lock mechanism. Depending on the design of the interlocking brick the locking mechanism may be found on the different sides of the brick or the top face of the brick.
You should able to see from the design of the bricks above that the single lock brick interlock at the sides whilst the perforated brick (with the holes on top) lock vertically and therefore “lock” like Lego.
The benefits of interlocking bricks include the reduction in the use of materials such as cement, iron rods and also eliminating the need for plastering (external or internal walls). This ultimately provides further cost savings. In addition, the process for building is also a quicker compared to orthodox construction.
At this current time the significant increasing cost of construction means that an alternative method to conventional building, such as ISSBs, are becoming more popular. This is a step, we feel, in the right direction as the more popular sustainable construction becomes the more it becomes widely available and a viable alternative to conventional construction.
