- The following appurtenant structures shall not be included in the height of the building unless the aggregate area of such structures including pent-houses exceeds one-third of the area of roof of the building upon which they are erected :-(a)roof tanks and their supports;(b)Ventilating, air-conditioning, lift rooms and similar service equipment;(c)roof structure other than plant-houses; and(d)chimneys and parapet walls and architectural features not exceeding 1 meter in height.
