Paragraph 1 Area
The area of–
(a)
a single-storey building for the purpose of regulation 3 shall be taken to be the total area, excluding any gallery or openwork floor;
(b)
a storey shall be taken to be the total area of the floors within that storey or, if the building is compartmented, within a storey of a compartment, excluding any gallery or openwork floor;
(c)
a room excludes any built-in fixture extending from the floor to the ceiling.