Stone Metal Coated Roofing Tiles

Superior Corrosion Resistance
The exceptional longevity of color-coated stone chip tiles, particularly in challenging environments, is rooted in a multi-layered defense system engineered for superior corrosion resistance. This begins with the foundation: high-grade galvanized steel (G300/AZ150) with a thick, hot-dip zinc coating (Z275+). Zinc sacrificially protects the steel substrate. Over this, a high-performance chemical pretreatment (often chromate-free) enhances adhesion and provides additional passivation. Next, a specialized corrosion-inhibiting primer coat is applied, often epoxy-based or containing active anti-corrosion pigments like zinc phosphate, which further blocks the electrochemical pathways for rust. The high-quality acrylic topcoat (base color) acts as another barrier, and finally, the dense layer of stone granules provides the ultimate physical shield against moisture, salt, and pollutants reaching the underlying metal. Crucially, all cut edges created during manufacturing or installation are factory-sealed or require field sealing to prevent exposed steel.

This multi-barrier approach provides comprehensive protection against various corrosion mechanisms. The zinc layer fights galvanic corrosion and protects scratches via sacrificial action. The primers and topcoats prevent moisture and oxygen ingress, stopping uniform surface corrosion. The stone granules provide exceptional barrier protection against abrasion, impact, and direct exposure to corrosive elements like salt spray, acid rain, or industrial fallout. The system is rigorously tested to withstand thousands of hours in salt spray (fog) chambers (ASTM B117) and cyclic corrosion tests (like Prohesion or CCT) that simulate years of real-world weathering, far exceeding the performance of single-coat painted metals or traditional materials like untreated steel or wood. Unlike materials that can rust through (like corrugated iron) or rot (like wood), this layered defense ensures the structural core remains intact for decades. This makes stone chip tiles ideal for coastal regions, areas with high pollution, industrial settings, and anywhere humidity and moisture are persistent challenges, outperforming asphalt shingles (which degrade) and requiring less maintenance than materials prone to rust or rot.