(1) A building classified as Group F, Division 3 is permitted to be of heavy timber construction or noncombustible construction used singly or in combination provided,
(a) it is not more than 1 storey in building height, and
(b) it has a building area not more than,
(i) 5 600 m2 if facing one street,
(ii) 7 000 m2 if facing two streets, or
(iii) 8 400 m2 if facing three streets.