I have a 1 1/2-story house with a basement from the 40s, built in white aerated concrete all the way up to the ridge on the gables. The intermediate floor is made of wood, the ground floor is concrete (as is the basement floor), and the roof structure is wood with incorrect additional insulation of sawdust and mineral wool done in the 80s. The house has two dormers in wood, where the walls also need to be addressed.
Moisture condenses on the roof sheathing because there is mineral wool in the roof, directly against the sheathing. An inspector has looked at it and determined that the roof needs ventilation, i.e., tear everything down, clean out old insulation, build up with spacers on the rafters, and make new insulation as well as new sheathing. BUT - he also says you should wrap the interior walls and ceiling from the inside and recommends installing mechanical ventilation at the same time.
I am going to hire this out but am unsure since I have read that it can be difficult to seal the film tight in old houses. Also, consider that there is aerated concrete on the gable walls (how good is it to wrap them?)
From what I understand, there are different alternatives that I would need help assessing:
1) Wrap interior ceiling and walls and create ventilation space in the roof, according to the inspector's suggestion.
2) Replace all wood (possibly not the rafters) and build as before, i.e., with sawdust or organic material, but not wrap interior walls and ceilings.
3) Other options?
I would be incredibly grateful if someone who has done this (and who has had moisture problems in a similar building) could give their recommendation on the best method. It seems to get different opinions depending on whom you ask.
But all well-founded experiences and tips are gratefully received by a confused homeowner...
If you also have tips on a GOOD company in the Stockholm area with experience in this, that would be excellent!
Thank you in advance!
