I want to isolate my attics lost. Q1: Being in a windy area, does the project make sense? Q2: Does cellulose wadding have better summer comfort than rockwool? Q3: A professional offers me to blow rock wool on old glass wool. Is it because he does not want to bother to remove the glass wool?
Loose insulation blown on the ground floor is a good solution. It is obvious that the lack of under-roofing screen is problematic in certain attics lost.
Cellulose wadding is supposed to have a better "phase shift" and thus offer a better summer comfort. I do not think that the thing was checked by a test laboratory... Disadvantage of cellulose wadding in bulk: its sensitivity to moisture in case of roof leak or snow penetration (always in the absence of under-roof screen).
I am always in favor of product consistency. So you guess my answer about keeping the "old" glass wool and adding a layer of cellulose wadding...
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