Section 410.501 - Weathertight Elements(A) A window shall be considered weathertight only if: (1) all panes of glass are in place, unbroken and properly caulked; and(2) the window opens and closes fully without excessive effort; and(3) exterior cracks between the prime window frame and the exterior wall are caulked; and(4) one of the following conditions is met: (a) a storm window is affixed to the prime window frame, with caulking installed so as to fill exterior cracks between the storm window frame and the prime window frame; or(b) weatherstripping is applied such that the space between the window sash and the prime window frame is no larger than 1/16 inch at any point on the perimeter of the sash, in the case of double hung windows and 1/32 inch in the case of casement windows; or(c) the window sash is sufficiently well-fitted such that, without weatherstripping, the space between the window sash and the prime window frame is no larger than 1/16 inch at any point on the perimeter of the sash in the case of double hung windows and 1/32 inch in the case of casement windows.(B) An exterior door or a door leading from a dwelling unit to a common passageway shall be considered to be weathertight only if:(1) all panes of glass are in place, unbroken and properly caulked; and(2) the door opens and closes fully without excessive effort; and(3) exterior cracks between the prime door frame and the exterior wall are caulked; and(4) one of the following conditions is met:(a) a storm door is affixed to the prime door frame, with caulking installed so as to fill exterior cracks between the storm door frame and the prime door frame; or(b) weatherstripping is applied such that the space between the door and the prime door frame is no larger than 1/16 inch at any point on the perimeter of the door or(c) the door is sufficiently well-fitted such that, without weather-stripping, the space between the door and the prime door frame is no larger than 1/16 inch at any point on the sides of the door or c inch at any point on the top or bottom of the door.(C) A wall, floor, ceiling or other structural element shall be considered weathertight only if all cracks and spaces not part of heating, ventilating or air conditioning systems are caulked or filled in as to prevent infiltration of exterior air or moisture.