Yes we did . My architect was against it because he was concerned about concrete onto grp ; the mass of that 35mm reinforced concrete . Now though it’s only the parking area that would have concrete on it . No idea if my architect will be happy with this . Went down the EPDM routine because that’s what he wanted .
As my architect said too me a few days ago “ it’s a learning curve “ - yeah , for both of us but with my money ? ?