Mud has been used as a construction material for hundreds of years. Recently, scientists discovered that it could be strong enough to build homes.
Now, scientists have discovered that, by adding certain chemicals to soil, it could be strong and sustainable enough to build homes in developing countries. In this blog, we look at whether this pioneering research may have uncovered an unusual alternative to bricks and cement for the future. Read on to find out more.
They are the tools of the house-building trade in this country, however, modern-day materials, such as bricks and cement, are environmentally damaging, as well as unaffordable for people living in the poorest parts of the world.
Scientists at the University of Bath are examining whether chemically altered soil could build sustainable, environmentally-friendly homes. They have discovered that, when alkaline chemicals, like those found in household cleaning products, are added to soil, the clay that is present is transformed into a geopolymer. This creates a kind of glue, akin to cement, which chemically binds the material together. The process makes the mud stronger, more durable and less likely to break down because of moisture. As a result, it could be a viable and robust construction material for building homes in the most deprived parts of the world.
The material, known as geopolymer-stabilised soil, can be typically fired at 80°C, as opposed to 1,000°C for ordinary bricks. This means that soil bricks have a far lower energy cost, are practical, affordable and environmentally sustainable.
Alastair Marsh, a postgraduate researcher in civil engineering at the University of Bath explained:
"The familiar construction materials of fired brick and concrete have a heavy environmental cost, with cement production alone accounting for 5-10% of global greenhouse gas emissions. Developing lower impact construction materials is an essential task to enable our world's growing population to house itself adequately without contributing to climate change."
Depending on the source materials and the required properties, he added, the stabilised soil bricks could have as little as half the carbon emissions impact of concrete and a quarter that of fired bricks. A typical family home, said Marsh, could be built using approximately 10 tonnes of soil by adding 5-10% sodium hydroxide. There is, however, a lack of clarity in understanding how the geopolymerisation reaction works for different soils so he is currently physically and chemically testing a range to improve on this. The research is key to developing sustainable housing in undeveloped parts of the world according to Professor Andrew Heath, of the University of Bath's Department of Architecture and Civil Engineering.
India is one country which may lead the way with a joint project already undertaken with the Indian Institute of Science in Bengaluru. Closer to home, the likelihood of the stabilised soil bricks being used for developments such as new homes, self-build, refurbishments and conversions, is a long-way off. So, the importance of protecting new properties with a structural guarantee and building control needs to remain a priority.
Having a 10-year-guarantee against structural faults or defects and knowing who your warranty provider is could be very important for the future of your home. Premier Guarantee are one of the UK's leading structural warranty experts. Get in touch today and find out how we can best support you