Staining near a coastal metal roof can involve environmental deposits, runoff, corrosion, or other local conditions. Its appearance alone does not establish the mechanism. Cleaning before documenting the pattern can remove useful diagnostic evidence.
What to do next
Photograph the affected areas and nearby components. Ask the contractor or manufacturer to review the condition before treatment. Keep the repair or cleaning method compatible with the finish, and avoid treating every stain as proof of general material failure.
Related Perkins guidance
Contact Perkins Roofing to discuss your roof and the appropriate next step.