How to measure the primary area
The primary area is measured to the inside of the surrounding walls for the primary part of the dwelling. Internal walls between primary areas must be included.
The ceiling height must be at least 1.9 m and the width at least 60 cm. In the case of areas with a sloping ceiling, the area up to 60 cm outside the height of 1.9 m must still be included in the measurement. In other words, the surrounding area where the height is less than 1.9 m.