We recently bought a house and are in the process of renovating.
The intermediate slab from the upper floor to the attic (currently not insulated at all) needs to have the insulation renewed.
The structure from below is as follows:Sheetrock/ Blue foil (vapor barrier)/ Mineral wool (destroyed and not airtight -> replacement)/ Particleboard.
Now we want to remove the chipboard on top, take out the old mineral wool, install new mineral wool and lay the boards on top with a spacing of about 1-2 cm.
In addition, the attic should be insulated between the rafters (-> mineral wool and just sheetrock in front of it). We were advised not to use vapor barrier to insulate between the rafters, or it was not considered necessary, as it will not be 100% waterproof afterwards anyway, and air circulation should be guaranteed in the old house anyway.
So far so good, but I have two big questions:
— What is the best way to remove the old mineral wool and get it out of the house?
There is only a mini-window in the attic, large bags of mineral wool won't fit in there.
Should I pack the absorbent cotton as tightly as possible in the blue bags on top of the attic and then move it through the house to the outside (or through the first floor window)?
I don't want to spread fiber all over the house, but I don't know how to get around that problem. Or am I being too fussy?
— Is this procedure normal? According to the roofer, it can be done the way we planned.
We also had to dispose of a lot of stuff when we demolished it. I stuffed it in blue bags and then put it in big bags at the junkyard that we got to use for it. I worked in a mask and goggles. But even though I showered, I still noticed these things on my body for a while. So pack the top as carefully as possible, closing all the doors (if possible) and then dropping them into closed bags.
I have a hard time accepting the idea that the mineral wool should have collapsed with horizontal installation. I rather suspect that the fill height was intentionally lower than the construction height of the ceiling joists. According to the description, there is only drywall under the joists, so only lightweight inserts are recommended. For that reason alone, I would put a question mark in front of the idea of installing more material there. Even if the joists underneath have a stronger deck, you don't have to put more material in there – that's the last word of wisdom. With insulation between the rafters, further insulation is planned anyway. I don't understand the idea of recycling at all, for if the same material is to be used again; then I would just add to it.