Tree roots from next door

[wardroom]

Need a little advice here, a colleague has some tree roots coming up through his patio, the offending tree or trees are from a neighbour.
I believe they are ash trees and they are mighty big.
He was going to mention this to the guy next door but before he does he wanted some facts regarding laws etc.
I said he might have to claim of the neighbours house insurance as they are his but I may well be way of the mark by suggesting this.
It is all private property so the council will not get involved.

Thanks in advance

 

[Max Power]

The neighbour is responsible. They are from his tree
There's a very good forum called Garden Law (www.gardenlaw.co.uk) where he'll be able to get advice