Hello, I am trying to build a lightweight roof, about 2.5x6.3m. A very simple pitched roof on a "attefallshus" with a 3° angle. I'm considering using sheet metal since it weighs the least. But then comes the problem with the condensation that forms underneath. Here I thought I would glue 30mm XPS insulation under a sheet metal roof that is corrugated on one side and smooth on the other, to break the thermal bridge without room for condensation to form.
The question is whether this is even possible. I envision the construction like this, from above: metal sheet, XPS 30mm glued with PU glue along the edges to the metal sheet and the joints, plus a few dabs here and there. And this rests on the roof beams with either roofing felt or age-resistant plastic. Then insulation between the beams leaving room for an air gap and finally age-resistant plastic and paneling.
My feeling is that this should prevent the severe condensation that comes from the metal sheet. By creating a "bubble" between the XPS and the metal where moisture cannot travel.
I hope someone can support my theory, or improve it
The question is whether this is even possible. I envision the construction like this, from above: metal sheet, XPS 30mm glued with PU glue along the edges to the metal sheet and the joints, plus a few dabs here and there. And this rests on the roof beams with either roofing felt or age-resistant plastic. Then insulation between the beams leaving room for an air gap and finally age-resistant plastic and paneling.
My feeling is that this should prevent the severe condensation that comes from the metal sheet. By creating a "bubble" between the XPS and the metal where moisture cannot travel.
I hope someone can support my theory, or improve it