ᐅ Insulation between roof rafters using Armaflex?? Question!!!!
Created on: 31 Jul 2018 09:55
K
Kiwi&Tina
Hello, I have a question about insulation between rafters.
We removed the ceiling on the upper floor and want to insulate and cover the sloped roof in some rooms.
From the outside, there are slate tiles, underneath are boards with bitumen membranes attached. My idea is to install 19mm Armaflex from the inside, then add fiberglass insulation on top of that.
I am an insulator but mainly in industrial settings, not roofs. Armaflex is vapor diffusion tight, which also concerns me...
The assembly from outside to inside would be: slate – bitumen membranes – boards – Armaflex – 140mm (5.5 inches) fiberglass insulation – vapor barrier – counter battens – 30mm (1.2 inches) fiberglass insulation – interior cladding.
Maybe someone has an opinion on this and could kindly share their thoughts.
Best regards
We removed the ceiling on the upper floor and want to insulate and cover the sloped roof in some rooms.
From the outside, there are slate tiles, underneath are boards with bitumen membranes attached. My idea is to install 19mm Armaflex from the inside, then add fiberglass insulation on top of that.
I am an insulator but mainly in industrial settings, not roofs. Armaflex is vapor diffusion tight, which also concerns me...
The assembly from outside to inside would be: slate – bitumen membranes – boards – Armaflex – 140mm (5.5 inches) fiberglass insulation – vapor barrier – counter battens – 30mm (1.2 inches) fiberglass insulation – interior cladding.
Maybe someone has an opinion on this and could kindly share their thoughts.
Best regards
G
garfunkel6 Aug 2018 19:48So the cross beams will form the new ceiling? The ceiling goes on these beams, and then the insulation is installed on top of that. Therefore, you would keep the cold roof and just raise the ceiling slightly higher?
Your main concerns would then be the sloped sections of the ceiling extending down to the floor or knee wall?
This would probably be less complicated to implement, although I’m not sure how to properly finish such a joint, especially regarding the vapor barrier.
You can likely find a professional through an online search; otherwise, I’m not sure how else to do it.
When I did this, I asked a local roofer and then sourced the materials through them.
I’m also just a DIY enthusiast without formal training, so I can’t give you precise advice.
Your main concerns would then be the sloped sections of the ceiling extending down to the floor or knee wall?
This would probably be less complicated to implement, although I’m not sure how to properly finish such a joint, especially regarding the vapor barrier.
You can likely find a professional through an online search; otherwise, I’m not sure how else to do it.
When I did this, I asked a local roofer and then sourced the materials through them.
I’m also just a DIY enthusiast without formal training, so I can’t give you precise advice.
K
Kiwi&Tina6 Aug 2018 22:46garfunkel schrieb:
So the crossbeams form the new ceiling? The ceiling goes on these beams, and then the insulation on top of that. So you would keep the cold roof and just raise the ceiling a bit? Not exactly, actually there should be no ceiling installed anymore, that’s the issue. It wouldn’t be a cold roof anymore. The rafters are to remain completely visible, only the roof slope up to the top would be covered...
G
garfunkel7 Aug 2018 16:03Then you should be able to create ventilation between the sheathing and insulation using battens. However, due to the thickness of the assembly, the rafters will likely no longer be visible. The only option would be a fake rafter, which can also look good.
An alternative would be external roof insulation. In that case, there should be no attic or loft remaining, and the ceiling up to the ridge beam would have to be removed throughout.
In this situation, there is really no way around consulting an expert or specialist.
An alternative would be external roof insulation. In that case, there should be no attic or loft remaining, and the ceiling up to the ridge beam would have to be removed throughout.
In this situation, there is really no way around consulting an expert or specialist.
C
Caspar20207 Aug 2018 16:17garfunkel schrieb:
In that case, you should be able to create a ventilation gap between the sheathing and the insulation using spacer battensProviding ventilation will be difficult anyway, since the lower part of the roof is sealed. Currently, ventilation is achieved through the wall vents.
garfunkel schrieb:
In this case, consulting an expert/professional is really unavoidableThat’s a good approach.K
Kiwi&Tina7 Aug 2018 17:58Ok, thanks for all the replies. I will look for a professional to handle this, everything else is a bit too much for me...
Best regards, Kevin
Best regards, Kevin
Similar topics