Keith Farquharson, BSc(Hons), MICE. This paper was first published in GE’s March 1986 edition.
It became widely known immediately after the last War, following investigation by the Building Research Establishment, that houses could be damaged by clay shrinkage in summer months due to water demands of adjacent trees. It was also known at that time that there would in general be partial recovery in the following winter when the water demands of these trees, and loss of rainwater due to evaporation, was less. A common solution at that time, if a tree were causing problems, was to remove the tree. It was known that if this were done the subsoil would partly recover, cracks would close to some degree, and very often little more was necessary than repair of what was often localised damage.