Cow dung bricks: stronger, cheaper and more sustainable

The worldwide demand for affordable homes increases, increasingly relying on extremely polluting building methods like fired bricks and cement. Dutch start-up Coolbricks offers an innovative solution for both problems. Their fully natural, bio-stabilized unfired bricks combine high-tech material science with low-tech mechanical innovations.

Made from earth, cow dung, and agricultural waste, the bricks offer several advantages, including cost-effectiveness, longevity, and the ability to regulate indoor climate by absorbing moisture. They are eco-friendly and contribute to a 90% reduction in CO2 emissions compared to conventional bricks. Coolbricks boasts that their bricks are 20% stronger and 50% cheaper, thanks to the abundant and locally available materials of earth, agricultural waste, and cow dung. At the end of the life span, the bricks are biodegradable and can be repurposed as fertilizer.

Coolbricks’ researchers identified fatty acids in cow dung as highly water-repellent. They extracted these ingredients and incorporated them into the bricks, acting as a binding agent. These turned out to make the bricks stronger and more water repellent than traditional bricks. The same mixture of earth, cow dung and fibres can also be used as mortar to further create cost advantages.

Coolbricks is starting with projects in Uganda, where affordable housing is particularly needed. In these economies, sustainability is considered a luxury. However, the low costs of the product make for a solution that is both affordable and sustainable.

Photos: Coolbricks