Complex sentence: Due to the social level of the envisaged occupants, "chambres de bonne" are characterised by their tight proportions; often around 10 m 2, and sometimes accentuated by being in a garret.
Split into simpler sentences: Due to the social level of the envisaged occupants, "chambres de bonne" are characterised by their tight proportions. The rooms often have a surface area of around 10 m 2, which is often accentuated by being in a garret.