Tree Related Subsidence

In winter a shrinkable soil generally increases in volume, in summer the reverse occurs. In summer where rainfall is reduced and evaporation through the increase in temperature is higher; a clay soil will shrink. In winter as rainfall increases and evaporation decreases; the soil will swell. Clay soils change their volume in relation to water content; they shrink as they become drier and expand as they become wetter acting like a sponge. These seasonal fluctuations can be made worse by adjacent trees and other vegetation. This can lead to a greater reduction or increase in the volume of a clay soil leading to enhanced ground movement and resulting in structural damage to a buildings foundations.