The subject of concrete can be a distressing one. Fortunately though, there are organisations who are developing solutions. CAT was founded in 1973 by engineers, architects, builders and growers, who wanted to steer away from a fossil fuel dependent society, and provide viable alternatives. The educational charity specialises in ‘sharing practical solutions for sustainability’ and offers an array of short courses and workshops including natural building, ecologically informed food growing, renewable energy and wastewater management.
They also offer various master’s degree programmes, including an MSc in Green Building, and in Sustainable Food and Natural Resources. These are renowned for their practicality and hail people from all over the UK and Europe.
To accompany their courses, CAT have released a series of reports with guidance for governments to achieve a carbon neutral society. These resources have existed long before the Net Zero Britain target was announced in 2019, yet they provide an invaluable guide for policy makers to reach this goal. Net Zero Britian is a legally binding contract to decarbonise Britain by 2050, a topic we will cover in more depth in another article.
So now that you have an insight into CAT, let’s see what they have to say about concrete and cement.
CAT argues that in many cases, cement can easily be replaced with more environmentally friendly alternatives. Lime-based render, mortar and clay plasters are perfectly sufficient are much healthier and environmentally friendly options. Instead of concrete block construction, CAT uses various materials including unfired earth, hempcrete and straw bales. Some of which are abundant and reusable, such as earth. Whilst others are renewable as they can be regrown. They can also be sourced more locally, thus reducing CO2 emissions through transportation. Hempcrete is a popular alternative to concrete and it is considered a ‘better-than-zero-carbon material’, as it stores more atmospheric carbon for the lifetime of the building than is emitted during extraction, construction and transportation.