Interlocking Stabilised Soil Bricks (ISSB)

Would you like to know how we are saving tonnesforest cover." The adoption of this technology will
of trees with every classroom we build? We not onlydramatically reduce this environmental damage.
looking out for education but also looking after theWe have been looking at these machines for the
Ugandan environment and keeping it green as wepast 6 years and today we are finally taking delivery
go.Thanks to some incredible fundraising fromof two machines.  The new machines make blocks
supporters Melinda and Steve Robinson fromfrom a specific soil called murram, cement and water.
Australia, we have just purchased two newIt takes 2 people to operate and can produce 300
Interlocking Stabilized Soil Block Machine (ISSB). In– 400 blocks in an 8 hour day. On top of all that
simple terms, a manual brick making machine, whichthey are also interlocking which saves on cement
will help with all of the building projects that we arecosts in between bricks. Several teams of Soft
involved in.Power Builders have been trained in the process in
Traditional methods of brick making in Ugandaassociation with The Haileybury Youth Trust.
comprise of taking a clay based mud and making aThe benefits of the ISSB bricks:
square block by hand, they are approximately the1.The making of 3000 ISSB blocks will save 10 tonnes
same size as any other brick elsewhere in the world.of trees.
The problem is that because they are made by hand2.The blocks do not need to be fired
they are not a consistent shape, and they come in a3.Cost saving because of less time needed to make
variety of sizes. After making the brick they are thenthem.
put into a pyramid stack with a gap in the middle4.Only one bag of cement is needed to make 150
where a fire is lit, they cover the top with bananablocks. (cement is incredibly expensive in Uganda)
leaves and dry grass (a handmade Kiln process). The5.They are double the size of a normal fired brick so
bricks are then fired for 96 hours - constantlyyou only need to use half the number of bricks.
keeping the fire burning with wood, and are left to6.There is no mortar needed between the bricks
cool for 4 days. The bricks are then stored for 4because of the interlocking system, so mortar is only
– 6 months before they are used.needed on top and bottom of the brick.
This whole process is:7.Uniformed shape for every brick, which uses less
1. Labour intensive,mortar and render – saves up to 50% compared
2. Bad for the environment because of the amountto using fired bricks.
of wood needed to ‘cook' the bricks,8.Are weather resistant and can be used in the
3. Makes the building process longer and moreconstruction of septic and water tanks. (There is a
expensive as the builders use more cement forcurved ISSB machine which can make curved bricks
mortar and rendering because of the imperfectionsfor water tanks)
of the bricks.9.The bricks are manufactured on site, saving
The new ISSB machine is an old technology thattransportation and damage.
originated in France over 800 years ago. Kenya over10.Bricks are used 4 hours after making them,
the past 25 years have redeveloped the systemtherefore construction can continue as the bricks are
because the Government has banned the cutting ofbeing made.
timber to fire bricks the traditional way, knowing11.The ISSB system uses Ugandan road base as its
what it was doing to the environment.main ingredient mixed with cement.
Since 1991, Dr Moses Musaazi, an engineer atWe will be using this type of brick in all buildings which
Makerere University in Kampala, has developed amade from brick machine and water tanks from now
technique which, by mixing soil and cement and thenon. This will make construction costs cheaper and the
compressing the dampened mixture in a mould,buildings and water tanks stronger. The biggest
produces an interlocking block (twice the size of abenefit – all monies fundraised for Soft Power
normal brick) that is stronger and more uniformlyEducation will now go further!Make sure to check
shaped than a conventional brick.back soon for an update on our new buildings using
Dr Musaazi says: "Cutting down trees for firing bricksthe new ISSB technology.
is second to charcoal burning in destroying Uganda's