Michael Nixon
Hi David, Apologies for the slow reply I've only just checked ask an expert, the best solution is as follows and will comply with building regs (an absolute must these days). If the existing felt is sound then overlay fully adhered insulation Kingspan TR27 150mm with 6by2 timbers to perimeter edges. Install 300mm deep upvc fascias to cover concrete and insulation upstand. Fit gutters and waterproofing membrane, we use EPDM with a 20yr guarantee. Fit trims and flashings. Need to look out for waste pipes etc we have done quite a few like this, I like to think it turns a concrete outhouse into a flat roofed extension. Rgds Mick Approved Rubber Roofing Contractors Ltd
