Chapter-7 General Building Requirements/ General Building Requirements/Provisions, Section 7.20 Lighting and Ventilation of Habitable Rooms

  1. All habitable rooms shall have, for ventilation, an opening directly to the external air or into an open verandah. The opening may not be more than 2.40 m in width. In case the owner/builder wants to construct an internal courtyard, the minimum dimensions of such a courtyard shall not be less than 3.0 m x 3.0 m for buildings below 15m in height unless mechanically ventilated.
  2. Where the lighting and ventilation requirements are not fully met through day lighting and natural ventilation, the same shall be further ensured through artificial lighting and mechanical ventilation. the minimum aggregate area of openings of habitable rooms and kitchens excluding doors shall not be less than 1/10 of the floor area. No portion of a room shall be assumed to be lighted if it is more than 7.50 m from the opening assumed for lighting that portion.