What factors influence the choice of metal panels for walls in coastal or humid regions1

Selecting metal panels for coastal or humid regions demands a specification approach that prioritizes corrosion resistance, moisture management, and long-term durability in saline, humid atmospheres. Material selection is the first determinant: marine-grade aluminium alloys with appropriate temper, or stainless steel grades such as 316, provide superior resistance to chloride attack compared with standard alloys. Anodized aluminium with a thick, hard anodic layer can offer good protection, but in severe salt-spray environments a high-quality PVDF or advanced powder coating over a corrosion-treated substrate is often preferred for long-term color and substrate protection. Fastener and connector materials must match or be galvanically compatible with the panel alloy to avoid bimetallic corrosion—this typically means specifying stainless steel fasteners or coatings that prevent metal-to-metal contact. Detailing to prevent ponding and salt accumulation is crucial: vertical joints, integrated drip edges, and ventilated cavity design facilitate drainage and drying, reducing prolonged wetting that accelerates corrosion. Sealants and gaskets must be specified for UV- and chloride-resistance and be accessible for replacement during maintenance cycles. Consideration of sacrificial or replaceable elements—lower-edge kick plates, water table panels—allows targeted maintenance without major rework. Coating system warranties, accelerated salt-spray testing results, and local field sample exposure tests are advisable to validate performance under project-specific conditions. Finally, lifecycle planning should include inspection and maintenance intervals adapted to the environment; coastal sites typically require more frequent checks of sealants, fasteners, and panel edges. With appropriate alloy selection, coatings, detailing, and maintenance planning, metal panels deliver durable façades even in challenging coastal and humid climates.