Great question. If a bench is going to live near a coastal boardwalk, salt spray isn’t a minor detail — it’s the main design driver. Salt accelerates corrosion, gets into joints, and makes standard steel hardware fail quickly. For coastal boardwalk benches, we treat the finish as a system rather than a one-coat solution.
First, we avoid unprotected carbon steel. Our default frame is a marine-grade aluminum bench design, usually 6061 or 6063 alloy, with a chromate conversion primer and a high-solids TGIC polyester powder topcoat. Aluminum doesn’t rust like steel, and the powder-coated bench surface seals the metal. Where steel is required for extra strength, we specify hot-dip galvanized steel and then powder coat it, but aluminum is usually the better call near salt air.
Second, the hardware matters as much as the frame. We use 316 marine-grade stainless steel hardware — bolts, screws, threaded inserts, and leveling feet. Standard zinc-plated parts will bleed rust within months. We also isolate dissimilar metals with nylon washers or plastic bushings to avoid galvanic corrosion.
Third, the shape of the bench is part of the protection. We use slatted seats and open frames with drainage paths so saltwater mist and rain don’t sit on the surface or collect in crevices. Rounded corners and smooth welds reduce salt traps. For wood-look seats, we often specify high-density polyethylene lumber or well-treated hardwoods, and we avoid sealing them tightly against metal without airflow.
Finally, we test for this. Our coastal finish packages are designed for C5-M marine exposure and are salt-spray tested to ASTM B117. In practical terms, that means a salt spray resistant bench should hold up for years on a boardwalk, not just survive one season. We still recommend a simple fresh-water rinse after storms or heavy spray — coastal benches last much longer when maintenance crews hose them down occasionally.
So that’s how we handle salt spray: marine-grade materials, a sealed powder-coated finish, stainless steel hardware, drainage-friendly detailing, and realistic maintenance. No finish is completely maintenance-free near the ocean, but the right combination comes close.