I want to build attic that are currently isolated by the wool blown (about 20 cm). Should this wool be removed before laying the floor or can we just cover it and compress it a bit?
Blown wool is a very good insulation solution with a good coefficient of thermal resistance compared to the thickness of the product. you can cover it. of a floor, provided that a vapor barrier has been placed on the floor on the side of the hottest room (ie the one that is under the eaves.) You still need to nail these panels on Make sure they can withstand the overweight, or you can make a dry screed with plasterboard or chipboard finish that you can then coat with the coating of your choice.
In fact, if you intend to develop and therefore heat your attic, the wool blown on the ground is not of great thermal interest (it can however mitigate the footsteps on the floor). So you could very well remove it.
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