Could animal blood be the next eco-friendly building material?
How could cattle become any more useful? Their hide is already used to produce leather, their milk is used for cheese butter and, well, milk, they taste great in a burger and continue to serve as draft animals in many parts of the world. British architecture school graduate Jack Munro has found a way to make a building material using one of the few materials from cattle that currently largely goes to waste – blood.
Munro’s “Blood Bricks” are created by first mixing fresh blood with an anticoagulant (EDTA) to prevent it thickening too quickly. Although he used bullocks, blood from other animals could also be used. He then adds sodium azide as a preservative to prevent decomposition and bacteria growth. After a number of unsuccessful attempts at creating a glue by adding chemicals such as glacial acetic acid, Munro turned to the simpler combination of blood and water that is then mixed with sand.
Placing the resulting mixture in formwork and baking it for an hour at 70° C (158° F) for an hour causes the blood proteins to coagulate to produce a stable, waterproof brick. With Munro estimating that 30 liters (7.9 gal US) of blood could be recovered from a single bullock and sand plentiful, he believes Blood Bricks have the potential to replace mud bricks as a building material in arid regions.
To this end, he is looking to raise enough money to build a prototype home using Blood Bricks in Siwa, Egypt. If he's successful, we might start seeing a lot of "red brick" homes being built in similar areas.