Height and depth
2. The height of–
(a)a building shall be taken to be the height from the surface of the ground to the underside of the ceiling of the topmost storey or, if the topmost storey has no ceiling, one-half of the height of the roof above its lowest part;
(b)a storey above the ground, or the depth of a storey below the ground shall be taken to be the vertical height or depth as the case may be from the ground to the upper surface of the floor of the storey, and the expressions “a storey at a height” and “a storey at a depth” shall be construed accordingly.