ᐅ Thermozell Eco 400 insulation layer too thick

Hello, I have a question. In the bedroom, we filled a bound fill layer to level out a slope of about 11-13 cm (4-5 inches). The lowest point was almost zero, and the highest was 11-13 cm (4-5 inches). So, we poured leveling compound in part of the room and then filled the rest with the bound fill.

Now, during the construction process, I made a measuring error, and the surface ended up 1 cm (0.4 inches) too high. Leaving it as is won’t work because I will end up too high compared to the living room. I already tried scraping it off manually and sanding it with an orbital sander. Even the wall sander only removed a thin surface layer.

Has anyone experienced a similar situation and can offer advice?

Best regards,
Natascha

Tool Rental: Screed/Concrete Grinder

Would it be possible to apply a 1 cm (0.4 inch) layer of Knauf leveling compound and then install our flooring on top? We would skip using the underlayment boards. I’m just not sure if the 1 cm (0.4 inch) layer would hold up or if it would crack under the weight of the furniture.

Does no one have experience with this? I thought there would be experts here, which is why I started this topic.

Here are laypeople building houses, not specialists for questions outside the standard scope.

I wouldn’t do it as suggested, but simply spend about half an hour milling calmly.

When I read about 13cm (5 inches) of loose fill and leveling compound, I think of many bags and, above all, a lot of weight. Is the ceiling load capacity sufficient to accommodate that much loose fill?