Section 14 in Tamil Nadu District Municipalities Building Rules, 1972
14. Ventilation of building.
(1)Every room, which is intended for human habitation, shall be furnished with sufficient number of windows and ventilators totally providing a ventilation area of not less than one-eighth of the floor area of the room, affording effectual means of ventilation by direct communication with the external air.(2)Windows and ventilators which open into a verandah shall be deemed to communicate with the external air, provided that such verandah is not more than 3.75 metres wide and open throughout its entire length, into space open to the sky, £he width of such open space being double width of the verandah, and in no case less than 1.75 metres.(3)Every domestic building shall be so constructed that every room intended to be used for purposes of human habitation shall have at least one side abutting for a length of not less than 2.5 metres on an open space, either external or internal. Such open space shall be not less than 1.7 metres in width.(4)A building shall not be held to contravene sub-rule (3) if one side of a room abuts on an external or internal verandah which in turn abuts for not less than half of its length on such open space.(5)Every open space external or internal required by the rule shall be, and be kept, free from any erection thereon and open to the sky.(6)This rule shall apply to kitchens and storerooms but not to lavatories and bathrooms which shall have windows or ventilators of not less than 0.5 square metres abutting such open space:Provided that the rule shall not apply to rooms provided with mechanical ventilation or air-conditioning:[Provided further that this rule will not apply to the plots in respect of the layout approved by the Director of Town and Country Planning or [Chennai] [Added by C. O. Ms. No. 3. R. D. & L. A., dated 2nd January 1982.] Metropolitan Development Authority in respect of [Chennai] [[Substituted for the word'Madras' by the City of Madras (Alteration of Name) Act, 1996 (Tamil Nadu Act 28 of 1996).]] Metropolitan Area or by the officers to whom such powers are delegated by them, for development by the Tamil Nadu Housing Board, the Tamil Nadu Slum Clearance Board and Quasi-Government Agencies.]
