This is in relation to my previous post //www.diynot.com/forums/building/rising-damp-or-not.291326/. I need to get a proper surveyor in to access my damp problem and he’ll want to access the sub floor. My flooring is chipboard and I cannot budge the majority of screws. I tried a screw extractor set which didn’t work and I drilled the heads off one of the smaller sheets and this still won’t budge. Due to some of musky smell transferring from the carpet to the floor I am planning on replacing the floor (and insulating at the same time) so with this in mind could someone give me some advice on the best way of removing the floor for the surveyor. It will still need it to function as a supporting floor until I replace it properly. My thinking was to circular saw around the edge over with the joists and use a special drill bit for cutting holes around the screws. My thinking is then it should just lift up and it will still be usable until I get a new floor.