Section 602.3 of the International Property Maintenance Code is hereby amended and shall read as follows:

602.3 Heat supply. Every owner and operator of any building who rents, leases or lets one or more dwelling units, rooming units, dormitory or guestroom during the period from October 1 to April 30, shall provide facilities capable of maintaining a temperature of not less than 68ºF (20ºC) in all habitable rooms, bathrooms, and toilet rooms.

Exception: When the outdoor temperature is below the winter outdoor design temperature for the locality, maintenance of the minimum room temperature shall not be required provided that the heating system is operating at its full design capacity. The winter outdoor design temperature for the locality shall be as indicated in Appendix D of the International Plumbing Code.