WAC 296-150C-0950
Roof coverings/membrane/weather
resistant. (1)(a) The roof covering must be securely fastened in
an approved manner to the supporting roof construction and must
provide weather protection for the commercial coach and the
occupants. The roof covering must be installed according to the
manufacturer's instructions and approved by us.
(b) Roofing membranes must be rigid enough to prevent
deflection that would permit ponding of water or separation of
seams due to snow or wind or during assembly or transportation.
(2) Exterior covering materials, including metal coverings,
must be moisture and weather-resistant and contain corrosion
resistant fasteners to prevent wind and rain deterioration.
Note:
Electro-plated, electro-deposited zinc, and electro-galvanized staples are not considered corrosion resistant materials.
(3) All exterior openings or penetrations into the
commercial coach around piping, ducts, plenums, or vents must be
sealed with moisture resistant material.