New Haven, Conn., Code of Ordinances tit. V § 301

No person shall occupy as owner-occupant or let to another for occupancy any dwelling or dwelling unit for the purpose of living which does not comply with the following requirements: (a)
Windows, skylights for lighting habitable rooms. Every habitable room shall have at least one (1) window or skylight facing directly to the outdoors. The minimum aggregate glass area of windows for habitable rooms shall be not less than one-tenth of the floor area of the room served by them and not less than ten (10) square feet. Whenever walls or other partitions of structures face a window of any habitable room and such light-obstruction structures are located less than three (3) feet from the window and extend to a level above that of the ceiling of the room, such a window 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 such room, the minimum aggregate glass area of such skylight shall be not less than three-twentieths of the total floor area of such room.
(b) Ventilation of habitable rooms. Every habitable room shall have at least one (1) window or skylight which can easily be opened, or such other device as will adequately ventilate the room. The total of the openable window area in every habitable room shall be equal to at least forty-five (45) percent of the minimum aggregate glass area of the window or skylight-type window as required in subparagraph (a) of this paragraph except where there is supplied some other device affording adequate ventilation and approved by the enforcing officer.
(c) Light ventilation for bathrooms. Every bathroom and water closet compartment shall comply with the light and ventilation requirements for habitable rooms contained in subparagraphs (a) and (b) of this paragraph except where the bathroom or water closet compartment is adequately ventilated by a ventilation system which is kept in continuous or automatic operation.
(d) Electrical fixtures. Every dwelling unit and all public and common areas shall be supplied with electric service, outlets, and fixtures which shall be properly installed, shall be maintained in good and safe working condition and shall be connected to the source of electric power in a manner prescribed by the ordinances, rules and regulations of the city. The capacity of such services and the number of outlets and fixtures shall be as follows:
(1) Every habitable room shall have at least one (1) duplex convenience outlet for every twelve (12) lineal feet of usable wall space, and every bathroom shall contain at least one (1) electrical convenience outlet.
(2) Every water closet compartment, bathroom, laundry room, public hall, and exterior stairway shall contain at least one (1) supplied ceiling or wall-type electric light fixture.
(e) Heating facilities. Every dwelling or dwelling unit shall be supplied with heating facilities which are properly installed, are maintained in safe and good working condition, and are capable of adequately heating all rooms, bathrooms and water closet compartments located therein to a temperature of at least sixty-five (65) degrees Fahrenheit at a distance of three (3) feet above floor level when outside temperature is ten (10) degrees Fahrenheit. Either central or space heating facilities may be used but must meet the following requirements:
(1) Central heating, central hot water facilities. Every heating unit and/or central hot water heating unit shall:
(A) Have every heat duct, steam pipe and/or hot water pipe free of leaks and functioning properly to provide an adequate amount of heat and/or hot water to the intended place of delivery;
(B) Be provided with seals between sections of hot air furnaces to prevent the escape of noxious gases into heat ducts;
(C) If employing electricity, be connected to an electric circuit of adequate capacity in an approved manner; and
(D) Be provided with automatic or safety devices and be installed and operated in the manner required by the statutes, ordinances and regulations of the State of Connecticut and the city.
(2) Space heating, unit hot water facilities. Every space heating unit and/or unit hot water facility shall:
(A) Not use gasoline as a fuel;
(B) Not be of the portable type if using solid, liquid, or gaseous fuel;
(C) If employing a flame, be connected to a flue or vent in the manner required by the statutes, ordinances and regulations of the State of Connecticut and the city;
(D) If employing solid or liquid fuels, have a fire-resistant panel beneath it;
(E) Be located at least two (2) feet away from any wall or be equipped with insulation sufficient to prevent the overheating of any wall in a manner prescribed by the current standards of the American Standards Association and the National Fire Protection Association;
(F) If employing gaseous fuel, be equipped with other than rubber tube connector;
(G) If employing electricity, be connected to an electric circuit of adequate capacity in an approved manner;
(H) Be installed and operated in the manner required by the statutes, ordinances and regulations of the State of Connecticut and the city. The standards of the New Haven Plumbing Code are those of the American Standards Association and the National Fire Protection Association.
(3) Oil-burning and other liquid fuel-burning space heaters prohibited after October 1, 1963; exception. Effective October 1, 1963, it shall be unlawful to use or maintain in any dwelling, dwelling unit, or rooming unit any oil-burning or other liquid fuel-burning space heater with the exception of existing kitchen ranges which are used for heating and/or cooking until July 1, 1967 [see § 13-828 ].
(f) Stairway, hall lighting. Every common hallway and stairway in every multiple dwelling shall be adequately lighted with lighting facilities sufficient to provide at least three (3) footcandles of light at the floor or stair tread level at all times. Every common hallway and interior stairway and exterior stairway and stairways in structures devoted solely to dwelling occupancy and containing not more than four (4) dwelling units may be supplied with conveniently located light switches controlling an adequate lighting system which may be turned on when needed, instead of full-time lighting.
(g) Screening. During that portion of each year when the enforcing officer deems it necessary for protection against mosquitoes, flies, and other insects, every door opening directly from a dwelling unit to outdoor space shall have supplied screens and a self-closing device; and every window or other device with openings to outdoor space, used or intended to be used for ventilation shall likewise be supplied with screens; provided that such screens shall not be required during such period in rooms deemed by the enforcing officer to be located high enough in the upper stories of buildings as to be free from such insects, and in rooms located in areas of this city which are deemed by the enforcing officer to have so few insects as to render screens unnecessary.
(h) Screens to basement openings. Every basement or cellar window used or intended to be used for ventilation, and every other opening to a basement which might provide an entry for rodents, shall be supplied with a screen or such other device as will effectively prevent their entrance.
State Law reference-- State requirements as to heat and hot water in dwellings, § 19-65, Conn. Gen. Stat. (Rev. 1958).