Hi, I am looking to buy a 1970 built house. I can see from underneath the roof there is polystyrene. Thin (10mm) sheets which are on top of the roof struts/beams with felt over them, then the outside tiles. The owner says they have been there forever, so cannot prove fire worthiness etc. Do they need to come off? And if so how? Do I just break them off, or does the roof need relaying? Or something else. Thanks
