I'm renovating our top bedroom and half the room is dormer style. I've no idea how to insulate this, could use some advice. The roof felt appears to be the old bitumen type. I'd obviously like the room to retain heat better but just as importantly, I want to reduce noise as we're on a main road. Its never been insulated before so no signs of damp/condensation and I'd like to keep it that way. Currently I think air can flow in under the eaves between rafters.
Do I need to keep a gap between the felt and insulation? Do I insulate between the pitched rafters up to the flat ceiling level and stop there or keep going? I guess it should be ok to insulate the flat ceiling part between the joists with loft roll above that. Do I use rigid type or Rockwool or a mix?
The rafters are only 75mm deep. I was thinking metal furring channels fixed across the rafters might be useful to give me another 25mm depth. Do I insulate between the metal channels? I thought 2 layers of plasterboard screwed to that would help down. Should one of the plasterboards be the insulated type with a vapour barrier? Thanks in advance all
keep the noise
Do I need to keep a gap between the felt and insulation? Do I insulate between the pitched rafters up to the flat ceiling level and stop there or keep going? I guess it should be ok to insulate the flat ceiling part between the joists with loft roll above that. Do I use rigid type or Rockwool or a mix?
The rafters are only 75mm deep. I was thinking metal furring channels fixed across the rafters might be useful to give me another 25mm depth. Do I insulate between the metal channels? I thought 2 layers of plasterboard screwed to that would help down. Should one of the plasterboards be the insulated type with a vapour barrier? Thanks in advance all
