The one-year project, part of the Academy’s Global Challenges Research Fund scheme, will look at the potential for using traditional Kenyan building materials such as cow dung, makuti [sun-dried leaves of the coconut palm], bamboo, grass, mud, coral limestone and calcined clays, as alternative building and construction materials.
Concrete is the most widely-used material in the world, with a carbon footprint to match. While adaptable and hard wearing, concrete is neither biodegradable nor environmentally friendly. Once it has started cracking, or becoming uneven, it needs to be smashed up and replaced, or covered with further layers of new concrete. Cement manufacture contributes to 5 -10% of all anthropogenic global atmospheric CO2 production.
Working closely with researchers at University of Embu in Kenya, the study will look at improving the properties and appeal of these traditional materials in order to improve their use. The project will share results with universities in Kenya and local communities to help create energy-efficient, environmentally-friendly buildings.
Principal investigator John Kinuthia, Professor of Innovation and Engagement in Civil Engineering within the School of Engineering, Faculty of Computing, Engineering and Science, and head of the Advanced Materials Testing Centre (AMTeC), said: “We need to look for alternatives to environmentally-unfriendly concrete. Despite being used for hundreds of years, these traditional materials have been put aside in favour of cement and concrete, and the resultant buildings end up with a very high carbon footprint that includes using a lot of energy either to heat up or to cool.
“These non-conventional building materials, that work with and do not despoil the environment, have the potential of insulating against heat loss, either from within or outside a building.
“Clays, for example, either neat or when mixed in with rice husks or cowdung, have been found to be durable, thermo-resistant, and have viable compressive strength; their usage has the potential to obviate the need for up to 50 percent of ordinary Portland cement.”