ᐅ Insulating the roof with kitchen paper/toilet paper

Hello,
I am not an expert, and before insulating my roof as described below, I would like to hear some opinions.
For simplicity, I am uploading a few pictures to help with understanding.

To begin with, I can get standard kitchen rolls very cheaply.

There is old fiberglass insulation with aluminum foil between the rafters, which is only about 60mm (2.4 inches) thick. The kitchen rolls are simply pressed onto it, and the 12mm (0.5 inch) OSB boards (12mm chosen for flexibility) are screwed onto the rafters. (Rafter thickness 160mm (6.3 inches))

The visible OSB boards are sealed at the joints with Isover tape, serving as the vapor barrier.
Additionally, I want to insulate the floor, possibly using 20mm (0.8 inch) polystyrene and OSB boards.

The questions I have regarding the method shown and described in the pictures are:
- Could this lead to mold?
- Is this prohibited from a fire safety perspective? Or are there roof insulation materials with similarly flammable properties that are nonetheless commonly used?

Honestly, my first thought was: April Fool’s Day is still a month away.

If the question is serious, hardly anyone has thought of that so far, and I don’t believe it would provide a controlled, even insulating effect. In my opinion, it’s possible to save money in the wrong place. You probably shouldn’t expect to hear something like “that’s doable” here.

I also had to double-check that today marks the beginning of March and not April.

Keep in mind that kitchen paper is designed to absorb moisture quickly. If your roof has a lot of moisture, you have to expect that it could turn into a soggy paper mess. To put it somewhat bluntly.

You can insulate with paper, but is it treated to be fire-resistant, or am I mistaken?

From a fire safety perspective, I think what you are planning is something that should be reconsidered very quickly.

It’s better to buy insulation materials that are specifically manufactured for this purpose.

I did the same, but with toilet paper. However, fire safety regulations only allowed three-ply rolls, so I had to remove an entire layer from the four-ply roll and then re-roll everything. It was a bit tedious, but it was worth it.

So, I know that my father used to insulate with cardboard... in old buildings, we have found fabric scraps and basically anything you can imagine. Considering the price of insulation wool at the hardware store, I’m not even sure if toilet paper wouldn’t be more expensive.

Sounds reasonable to insulate that way ☺. I have an apartment for rent where they used newspaper and other waste materials for insulation and construction. Oops, the building was from the 1950s, so there weren’t many options back then...

... and by now I have had it properly renovated.