I need to prepare an interior wall. Currently, the wall looks like this (from inside to outside): a wallpapered, porous wood fiberboard, (Tretex?), studs about 10x10cm with chips in the cavities, some form of old wind barrier/paper, wood paneling. I'm wondering if it's possible to install studs directly on the Tretex and insulate with 45mm mineral wool. My questions are whether I should use plastic or some other form of barrier directly against the Tretex or not. Can as little as 45mm mineral wool cause condensation problems inside the wall? Can the Tretex itself cause problems in the future? The wall will be properly insulated from the outside within 1-3 years in conjunction with an extension.
Construction veteran
· Åland
· 2 076 posts
I would not be worried about installing 45 mm mineral wool internally. However, there is nothing wrong with installing a diffusion barrier on the inside, but there should be asphalt paper or similar inside the porous board.
Construction veteran
· Åland
· 2 076 posts
If there are spån in the wall, there should at least be a papp to prevent spån leakage. Check in a vent or disassemble an electrical outlet and maybe you can see.
Considering that you're going to add even more insulation externally, isn't it appropriate to put the plastic in place already now?
When you have torn down the facade, you should put paper on the outside before the new layer of insulation. Finish with a windbreaker on the outside under the new facade material.
When you have torn down the facade, you should put paper on the outside before the new layer of insulation. Finish with a windbreaker on the outside under the new facade material.