Hi I don't know if it was tree damage that caused it but i doubt it but we are at the bottom of a hill. Our structural engineer told us: Camberwell Dulwich areas area largely LONDON clay soil, combined with hills and there is a lot of subsidence in the area as a result. The flat was underpinned before we moved in and the council did it- there was little information provided to us by them about why- but the clues from reports told us that cracks consistent with subsidence would have lead to them doing it. Since the work was done no cracks have reappeared so we are glad that it was done. The council insure our property structurally as part of the service charge. We have not had a problem with contents insurance. Toulouse