§ 63. Two story transient dwellings. 1. All nursing and convalescent homes, homes for the aged, and boarding and nursery schools, two stories in height, shall conform with all of the provisions of article four.

2. Except as provided in subdivision one of this section, the only provisions of article four which shall apply to two story transient dwellings in existence on July first, nineteen hundred fifty-two, shall be sections sixty, sixty-one, sixty-five, title two and the following:

a. Every such transient dwelling shall have at least two means of egress. The first means of egress shall be by an interior stair closed off at the top or bottom. The second means of egress shall be by an additional interior stair closed off at the top or bottom or a fire stair or fire escape. A second means of egress shall not be required in a dwelling containing less than thirty sleeping rooms if the sill of the second story window does not exceed fourteen feet in vertical height above the ground or other safe landing place immediately below such window sill.

b. Where it is impractical in such transient dwellings to provide a second required means of egress, the department may order, in lieu thereof, additional alterations to the first means of egress and to shafts, stairs and other vertical openings to safeguard the occupants of the dwelling, may require the public halls providing access to the first means of egress to be equipped on both stories with an automatic sprinkler system, and may also require automatic sprinkler heads in the stair which serves as the only means of egress.

c. Where two means of egress are required by this section and one is an ornamental stair, the provision for closing off the stair at top or bottom shall not be applicable to the ornamental stair.