(A) General. Every habitable room shall have at least one window or skylight facing directly to the outdoors. The minimum total window area, measured between stops, for every habitable room shall be 10% of the floor area of the room. Whenever walls or other portions of such structures face a window of any such room and such light-obstructing structures are located less than five feet from the window and extend to a level above that of the ceiling of the room, such a window shall not be deemed to face directly to the outdoors and shall not be included as contributing to the required minimum total window area. Whenever the only window in a room is a skylight-type window in the top of the room, the total window area of the skylight shall equal at least 15% of the total floor area of the room.
(B) Habitable room. Every habitable room shall have at least one window or skylight which can easily be opened or such other device as will adequately ventilate the room. The total openable window area in every habitable room shall be equal to at least 45% of the minimum window area size or minimum skylight-type window size as required or shall have other approved, equivalent ventilation.
(C) Bathroom and toilet rooms. Every bathroom and toilet compartment shall comply with the light and ventilation requirements for habitable rooms, except that no window or skylight shall be required in adequately ventilated bathrooms and toilet rooms equipped with an approved ventilation system.
(Prior Code, § 1606)