I've had an extension built with a flat roof, the roof has been felted and looks tidy. But when the building inspector came out he questioned the fire rating of the materrial, and that if the material doesnt meet a certain spec I will needto put bitchumen chipoping on top. The chap who did the roof is proper old school i asked him what stuff he used his reply was 'good stuff' following that all he could tell me that its polyester based 2 layers of 2mm & 1 layer of 4mm, and its got a silver finish. I would have thought most products now have a suffucient fire rating so you don't have to have the chippings on top. Is this the case, does anybody know what product he might have used or something similar with suffucient fire rating so i can tell the inspecter a certain 'brand' that he would be happy with.
Any help would be gratefully received.