2. This act applies to a building the construction of which begins after the date of the coming into force of this section but does not apply to a building intended exclusively for the use of a natural person and his family if that person himself carries out the construction of the outer shell of the building, nor to buildings excluded by regulation.
It applies also, and with the same exclusions, to an addition made to a building and on which construction work begins after the date of the coming into force of this section.