Redb00l
2013-02-27 19:30:24
- #1
Hello
I would like to carry out internal insulation as shown in the attached picture.
Briefly - Outside: 240´ wall with plaster
Inside: air gap of 8 cm then PU rigid foam boards and then plasterboard.
According to calculations with wufi, I have a moisture content of 132 kg/m³ in the masonry and also 18 kg/m³ in the air gap.
If I indicate in the calculation that the external wall is "tight", e.g., as a test, I hang a PE foil in front of it, I still get values:
Masonry: 16 kg/m³
Air gap: 1.7 kg/m³
For fun, with ETICS still 6 kg water in the masonry.
What is best in this case I know - external insulation.
1st question: What can be done so that as little moisture as possible penetrates from outside but, if possible, water can still diffuse outward.
Or in other words - if I want to insulate like this - what must I especially consider so that moisture in no case condenses in the air gap?
The dew point lies in the insulation layer between the 1st and 2nd PU board.
The 2nd question: Should I place the vapor barrier directly behind the plasterboard, i.e., the battens, or could I also place it between two PU boards? Otherwise, I would have to use counter battens to be able to attach the recessed boxes.
Thank you very much in advance
Best regards Mirko
I would like to carry out internal insulation as shown in the attached picture.
Briefly - Outside: 240´ wall with plaster
Inside: air gap of 8 cm then PU rigid foam boards and then plasterboard.
According to calculations with wufi, I have a moisture content of 132 kg/m³ in the masonry and also 18 kg/m³ in the air gap.
If I indicate in the calculation that the external wall is "tight", e.g., as a test, I hang a PE foil in front of it, I still get values:
Masonry: 16 kg/m³
Air gap: 1.7 kg/m³
For fun, with ETICS still 6 kg water in the masonry.
What is best in this case I know - external insulation.
1st question: What can be done so that as little moisture as possible penetrates from outside but, if possible, water can still diffuse outward.
Or in other words - if I want to insulate like this - what must I especially consider so that moisture in no case condenses in the air gap?
The dew point lies in the insulation layer between the 1st and 2nd PU board.
The 2nd question: Should I place the vapor barrier directly behind the plasterboard, i.e., the battens, or could I also place it between two PU boards? Otherwise, I would have to use counter battens to be able to attach the recessed boxes.
Thank you very much in advance
Best regards Mirko