I will be self building a two storey extension onto the rear of my property and I've been busy phoning around the insurers to try to get a structural defect warranty. It appears that unless my extension is greater than 50% of the original house volume that no one wants to know. I've tried zurich, premiere, build zone, BLP and can't get through to NHBC yet, but none of them will cover it. Two of these even expressed surprise that I was trying to get a warranty for my size of build (about one third of the original house volume). My quandry of course is what happens when I come to sell the house and the buyers' solicitor inevitably asks for a structural defect warranty. I haven't tried the architect's certificate route yet, maybe they do this sort of thing.
Has anyone been through this, if so heeeeeelp