Hydraform block

The Hydraform Interlocking Soil Block (hydraform block) is an interlocking earth block used in many African countries for construction purposes. The hydraform block is made from soil cement which is a mixture of soil, cement and water, and is hydraulically compressed to form a high quality interlocking soil block. Soil from the building site can be used to manufacture building blocks. Sandcrete and landcrete are similar materials but are not compressed.

The Hydraform compressed earth block is very popular due to the cost savings that are involved during the construction process as only around 30% of the structure requires mortar between the blocks. Due to the interlocking nature of the stabilized soil block, unskilled labour can be utilised in construction thereby empowering rural communities and creating jobs.

The blocks interlock top to bottom and front to back. Blocks dimensions are 220 millimetres (8.7 in) wide, 115 millimetres (4.5 in) high and 230 millimetres (9.1 in) long. It weighs approximately 12 kilograms (26 lb). Once blocks are manufactured it is "wet cured" for a period of 14–21 days to reach desired strength.

The inventor of the current Hydraform concept which has been in use since the year 2000 Mr. Joachim Kofahl (https://www.google.com/patents/WO2001058654A1?cl=de ) There have been more than 3,000 Hydraform machines manufactured and sold worldwide between 2000 and 2016 [7]

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