Roofing

Very noisy (as a result of movement) dorma roof

Anonymous user 09/03/2024 - 3.25 PM

Hi, I've got a new dormer loft roof, which is aprox 6m x 4m, it's been on for almost exactly a year. The problem is that we get excessive noise (and I assume therfore at least some movement) from the roof as it heats and cools. It's most noticeable on sunny autumn / winter days, but happens most days with creaks / pops / growns more or less constantly in the morning / evening with some loud enough to be audible downstairs. It's a warm roof make up. As the roof is only about 24m2 no expansion joints were installed. The make up is GRP covering over 18mm interlocking osb ontop of 125mm foil backed insulation which sits directly ontop of the joists (no timber deck, or vapour control layer between joists and insulation). There is a thin plastic sheet vcl between joists and plasterboard, but it's peppered like a culinder with screw and downlight holes. The OSB top deck is screwed down (just screws with naked heads, no plastic inserts) to the joists at about 300mm centre's. My concern is that it's not sufficiently well fixed down and so the movement that serenades our bed times will eventually lead to cracks and water ingress. Is this something that could be fixed by adding more fixings through the grp onto the joists (with the plastic inserts) and then patching / redoing the grp? Is the lack of timber sheets and VCL under the insulation a major problem when the joints between the insulation sheets have been sealed with expanding foam and we do have at least some vapour contol behind the plasterboard? Greatful for your thoughts!