Striped insulation?

[Karl_Pedal]

I'm lowering a ceiling and therefore removed the existing inner ceiling. Then the insulation became visible and I was startled when I saw it. Dark color! Oh no, mold? However, it doesn't seem so because it is regularly striped all over the insulation, and if you touch these stripes, you can feel that it's a slightly stiffer surface than where it's not dark. What is this and what is it good for?

 

[Klasklättermus]

looks like you have insulation with paper on it.
which is then used incorrectly.
normally placed against the ventilation. not at the bottom against the plastic

 

[Karl_Pedal]

That is something the previous owners did about 13 years ago. What function do the stripes serve?

 

[Klasklättermus]

That is something that a previous owner did about 13 years ago. What function do the stripes serve?

normally it's nothing at all except brown paper (it can be product name and manufacturer).
would cut a slit and smell what it smells like.

 

[Karl_Pedal]

It smells like nothing at all.

 

[Needas]

I'm lowering a ceiling and therefore removed the existing inner ceiling. The insulation became visible and I was startled when I saw it. Dark color! Oh no, mold? However, it doesn't seem so because it's regularly striped across the entire insulation and when you touch these stripes, they feel a bit firmer than where it's not dark. What is this and what is it good for?

[image]

Insulation known as byggmatta, which was commonly used for insulating attic floors in the past! A combination of insulation and windproof paper that is impregnated to withstand small amounts of moisture.