The researchers are working hard on upgrading one ancient building material. The first stage of the research has just brought back the results, and the good news is that they have been able to improve it to fit in the modern thermal standards.
The collaboration between French and UK researchers has an appropriate name – CobBauge, which is a combination of French and English words for the material. The team of researchers is led by professor Steve Goodhew, working at the University of Plymouth.
The first stage of the project will finish at the end of March 2019. During this early stage, the team was able to improve the ability of the cob to trap heat inside the buildings. They have managed this by using two different grades of cob – a stronger version and a lightweight version that is better at insulating. They bonded the two to form walls of the material.
Why are the researchers improving this ancient material?
The cob is made by mixing earth, water and fibres (straw or hemp). Because of this, it can reduce construction waste and CO2 emission. Furthermore, the idea is for the materials to be sourced on the site. The problem is that the cob as we know it doesn’t comply with modern thermal regulations, despite it being used for the building of houses in England and France in the past.
Professor Goodhew believes that the team has invented a “modern interpretation” of cob and he hopes that the new material will satisfy those looking for new, high-tech materials and the traditionalists.
Dr Jim Carfare, working at the University of Plymouth as a lecturer in Environmental Building said that the next phase would be the thorough analysis of the conditions inside buildings built by using this new material.
According to dr Carfare, they want to build real CobBauge buildings and put them to the test in actual environmental conditions over a longer period. The idea is to test the thermal performance, humidity and energy use of the material. He believes that the general public slowly realises that the use of current building materials can have some negative consequences and that in the future natural material like cob might be more interesting.
Professor Goodhew claims that the research suggests that cob can be used to build modern houses according to the latest standards.
So far, the team has been adding natural fibres in the new cob, but the idea is to try to add more recycled materials, like end-of-life paper fibres.
After securing funding, the second stage of CobBauge research will feature at least two houses built with the new material. Researchers will have to train builders to use new material and publish new building guidelines as well.