But what exactly is cob, and how can it be used in building?
Cob and clay walls formed an important part of the new classroom at Castle Hill School.
‘Cob’ simply means ‘lumps of earth’. Earth is the oldest building material in the world and there are many cob buildings around the UK. Lumps of moist earth (clay/sand mixed with straw) are formed with the hands, then pushed and smoothed into place, also by hand. This means that cob walls can be created in any shape and that anyone can learn the simple building techniques needed.
Benefits of building with cob
- Cob is natural, safe and non-toxic
- It is warm and strong and can withstand the elements in the UK climate
- Cob lends itself to curved or organic shapes so is great for many creative building projects
- Earth is a low-impact material – it can be sourced locally and does not require intensive production processes
- It is easy to obtain and simple to build with, making it an accessible and inexpensive way to build
For more ideas, take a look at the blog of Michael Buck, who famously built his Oxfordshire cob home for just £150 just a few years ago!