Hi, thanks for your response. Why would you use a second deck and how would you fix it? Any sort of nail or screw through the decking and PUR would surely compromise the performance of the VCL?
After researching and watching Celotex video guides I have started to build a flat roof to my extension. The roof is 7.2m long by 2.2m wide. The decking will be T&G 18mm OSB3, a VCL topped with 100mm of PUR insulation and a finishing layer of EPDM. There will be two roof lights on the roof. A...