Simple mud concrete bricks provide the most affordable and sustainable houses in the tropics, a Sri-Lankan study suggests. Comparisons of four different types of walling materials revealed that mud concrete bricks have the lowest environmental impact and keep houses cool. They are also the cheapest, and easiest to dispose of when it may become necessary to knock a house down.
Researchers compared mud concrete bricks with red bricks (modern fired clay bricks), hollow cement blocks and Cabook, the Sri Lankan name for bricks made from laterite soil, which are common in the tropics. The goal of the study was to find out which types of walling material are the most suitable for constructing affordable houses in the tropics, where population density and poverty are generally high.
Mud concrete bricks are also the cheapest, at less than US$1,000 in Sri Lanka for an average-sized house, whereas red bricks cost nearly US$3,500. Mud concrete bricks are widely used in many other tropical countries.
“Why spend more money and destroy the environment more?” asks Rangika Halwatura, a civil engineer at the University of Moratuwa in Sri Lanka, and one of the authors of the paper.
Mud concrete bricks are made from soil in the same way as traditional mud bricks, but contain gravel and sand to improve their strength. The researchers looked at the carbon footprint of all four walling materials, and found that mud concrete bricks were the most environmentally friendly to produce and dispose of.