Hello.
I live in a 1950 house on a busy road and it has a dormer roof. I'm accustomed to the traffic noise, but am now selling the house and some viewers have said it is too noisy, so I'd like to try and tackle that.
When I had the rooms decorated, I had insulation put in between the rafters and they used some blue acoustic plaster board. This didn't seem to have a great deal of effect. I think that's most likely because they used thermal insulation that wasn't designed for acoustics, I don't know. Certainly, I don't think the hollows between the inner walls and the roof have insulation in them, so that could be the issue. The window is new, double-glazed with laminated glass of different thicknesses so it shouldn't be that.
What could I do to improve matters? The loft has insulation, but there is a gap at the edge - I think insulation could be slipped into the gap so that it slid down the angle of the roof and into the 'cheeks' of the dorma. Would that be a viable option? I'm loathe to cutting away the plasterboard inside the rooms because of all the extra decorating, but if it has to be done, so be it.