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Not by itself, but it will help retain the generated heat, something that I know to be rather important in a country that gets down to minus 30C or so in winter.

These are inside walls, meaning there is another room on the other side, so in my opinion this insulation is useless anyways. The original inside walls are raw wood planks, and then usually tension paper on top, wood panels if business has been good, clay has also been used and later on that wood pulp thing. I’ll update when I reveal the original timber frame that is on the outside walls, which I’ve yet to see at all!