What is this fleece under the carpet? - Old building

Hello everyone,

I am currently planning the renovation of my attic. It was converted in 1973 (previously a conversion reserve) and altered again in 1992.

The same carpet is laid throughout the entire floor (whether it is still from the original conversion or from 1992, I do not know). It is now supposed to be replaced with something modern. Yesterday, I peeled off a corner to estimate how much work is ahead of me. Of course, it is fully glued down, which I had already expected. What makes me hesitant, however, is the structure: under the carpet there is first a layer of crumbs – that was probably once the bottom side – and then a fleece made of fine, white-gray fibers. When pulling it off, the fleece willingly came off the floor together with the carpet, but the fine fiber structure doesn't quite sit well with me.

Occupational safety is already an issue due to old KMF and fiberglass insulation in the attic, but could there be problematic stuff lurking here? Does anyone know this material and how to deal with it?

Grateful for suggestions and advice,
Your Schwenkgrill

The fleece is part of the backing layer of the carpet. This is how carpet used to be manufactured. The "crumb layer" provided stability to the carpet, acted as impact sound insulation, and above all, prevented the carpet from slipping. Over time, the plasticizer dissolves and the aforementioned crumbs remain. However, there should be no problems. When removing it, simply ensure good ventilation, and if you are very sensitive, get a dust mask from the hardware store.

Thank you for your assessment. We removed the carpet today, and it went without major problems. The air wasn’t too thick afterward, but we were wearing coveralls and respirators anyway. Since we also removed the substructure at the same time (old chipboard), the complete removal was not an issue. Whatever came off with the carpet stayed on the carpet; whatever stuck to the substructure just stayed stuck. I’m just glad that this chapter is now done.