(1) The roof covering must be securely fastened in an approved manner to the supporting roof construction and must provide weather protection for the vendor unit and the occupants.

(2) Exterior covering materials, including metal coverings, must be moisture and weather resistant and contain corrosion resistant fasteners to prevent wind and rain deterioration.

(3) All exterior openings or penetrations into the conversion vendor unit or medical unit around piping, ducts, plenums, or vents must be sealed with moisture-resistant material.