Lesser of two evils.

[mowerman]

I have a mature TPO oak tree close to the house. It has fungus at the base with rot in the trunk.
An arborist has indicated that for safety reasons the tree will soon need felling.
However  we’re on clay soil and reading some surveyor’s advice online they suggest removing the tree could cause heave with damage to foundations due to the ground re hydrating. That said I’ve read conflicting arguments from surveyors and arborists both agreeing and disagreeing with this observation.
Thoughts?

[markc]

Yes you could get heave, but you WILL have a tree falling sooner or later.

[Radian]

38 minutes ago, markc said:

but you WILL have a tree falling sooner or later.

Probably sooner.

We had a lovely old Walnut in our back garden. Had a kids swing tied onto the perfect branch for the job. There was evidence of rot in the upper root but we ignored it for a year or so. One day I looked out and noticed the swing almost touching the ground! Overnight the tree had listed dramatically towards the neighbours garage. We spent quite a while worrying while we organised for it to be felled.

[George]

If there's no sign of cracking due to ground movement caused by soil shrinkage or swelling already, then I wouldn't anticipate a problem with swelling following a tree removal. 

 

That said, if you are definitely on shrinkable clays and the house has shallow (<600mm) foundations, then as a precaution you could have the tree removed in two hits. Remove 50% one year and the rest the following year.