Hello there, I'm thinking of having my flat roof insulation repaired. I am waiting for one of the tradesman of the community to reply to me but I know there is a certificate that needs to be provided that lasts 10 years. My question is: how do I make sure the certificate is the right one? Does it have to carry a specific name ? I lost so much money for the roof insulation in the past that now I'm very careful. Please help me... thank you very much
