How do you mean “used on a roof”? Do you have pictures? We don’t know your location and it may make a difference.
Many energy companies state that it needs to be protected from mechanical damage and corrosive environments e.g. Flexible gas piping OK for exterior? post # 21 from 11 years ago.
This is from Duke energy:
When installed outdoors, CSST shall be protected from mechanical damage. A conduit or chase is required for installations in exposed unprotected areas within 6 feet of grade. Conduit shall be supported with proper size pipe hooks, pipe straps, bands, or hangers.
Protective coating must remain intact outdoors. Mechanical joints and associated exposed metal tubing shall be wrapped or protected by shrink sleeves. Appropriate measures must be taken to shield CSST from corrosive environments such as exposure to acid or chloride based cleaning solutions for brick or masonry.
Where passing through an outside wall, CSST shall be protected. CSST must be sleeved where passing though.
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