How poorly built is this wall construction/gable

[martin h82]

Wondering how common or poorly constructed my wall is and how it should have been done instead? I've made a simple cross-section view of my gable wall to describe the problem, but the stud marked with ? is black on the underside and my theory is that indoor air has entered the wall, risen up, condensed on the underside, and the moisture then has nowhere to go. House built in 1960.

 

[Huddingebo]

Is there a vapor barrier in the wall?
Are all the building elements you have drawn original?

 

[martin h82]

Is there any vapor barrier in the wall?
Are all the building elements you have drawn original?

Yes and yes, the vapor barrier is a paper but aluminum foil

 

[Isakare]

Had the same construction and problem on my house built in '66

 

[martin h82]

Had the same construction and problem on my house built -66

What did you do about it?

 

[justusandersson]

In 1960, vapor barrier was an almost unknown concept, at least among ordinary builders. It was required according to BABS 1960, but probably didn't become widespread until a few more years later. The most common vapor barrier that emerged was asphalt paper. Building plastic did not exist at all in the 60s. The main reason for the introduction of vapor barrier was that condensation reduced the insulating ability of mineral wool. You can't talk about construction defects when a house is built in the manner that was customary when it was built. Then I find the section through the gable wall a bit unexpected. It is usually the case that the wood shaving insulation goes all the way out to the gable panel.

 

[martin h82]

Then I think the section through the gable wall is a bit unexpected. It is more common for the wood fiber insulation to extend all the way out to the gable panel.

Thanks for the info, regarding the wood fiber, it extends over the wall and out towards the panel, just a slightly unclear sketch

 

[Isakare]

What did you do about it?

Steam barrier according to advice from a carpenter.
Removed all ceiling moldings, sealed all joints in the plasterboard with latex sealant. Painted 3 layers of paint carefully on walls and ceiling, 2 layers of 20 or 30 gloss and then a layer of regular wall paint 7 gloss, wallpaper on the walls we wanted it after the paint.
The paint acts as a layer of plastic and drastically reduces the vapor pressure.
I cleaned the damage with chlorine and painted on Cuprinol wood preservative (probably no longer available for purchase).
Furnished the attic after that, so I never accessed the area again to check.