If a DECRA roof system is installed with the panel resin coat underside left exposed to the outside air, the panel resin coat alone is not sufficient protection against the elements. This is especially true when such structure is near saltwater.
An example of an open air, open rafter building would include structures like a gazebo, boathouse or other outdoor roof cover not using a solid roof deck and roofing underlayment prior to installing a DECRA roof system, thus leaving the DECRA roof panel underside resin coat exposed to outside air.
If DECRA roof panels are installed in this manner, the panel underside resin coat surface must be coated with a finish paint coat system of sufficient quality to protect against potential future surface corrosion. Consult your paint store specialist to recommend an industrial primer and finish paint coating suitable for a protective anti-corrosion metal surface finish. Follow the coating manufacturer’s surface preparation directions prior to applying the protective finish paint coat system.
The combination of the DECRA metal roof panel anti-corrosion hot dip alloy coating — a blend of both aluminum and zinc in proper proportion and thickness for maximum effectiveness — along with a quality metal finish paint coating system will provide overall optimal protection for exposed underside resin coat roof panel surfaces.
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