Yes—in most real-world coastal settings, salt air will damage a basic metal outdoor bench faster than a solid wooden park bench. I have seen it happen in my own yard: the metal bench by the fence started rusting around the bolts and base within two seasons, while the wooden bench only turned a little silver-gray on the surface.
The main reason is how salt air works. Coastal air carries tiny droplets of seawater or dry salt particles that become salty again when humidity rises. On metal, salt acts as an electrolyte. It pulls moisture from the air and creates the perfect conditions for oxidation. Bare steel, wrought iron, and even thin or scratched powder-coated metal can start rusting quickly. The damage usually appears first at joints, welds, scratch marks, and hidden areas where salty moisture lingers. Once rust gets under the coating, it spreads underneath and flakes the finish off.
Wood is not immune, but the failure is usually slower and less aggressive in the short term. Salt air can dry out wood, draw out its natural oils, cause surface checking, and turn it gray. Cheap pine or fir may swell and shrink repeatedly, leading to cracks, warped slats, or rot if water sits in the joints. But a dense hardwood bench—especially teak, ipe, shorea, or white oak—handles coastal exposure far better. These woods contain natural oils and tight grain that resist moisture and salt penetration. A quality wooden park bench might need cleaning and oiling once or twice a year, and it can still last 10 to 20 years near the coast.
That said, the comparison depends heavily on the type of metal and the quality of the finish. A cheap painted steel bench will probably show rust in the first year or two near salt water. A marine-grade aluminum bench, 316 stainless steel bench, or properly galvanized steel with a thick exterior powder coat can last decades with just occasional rinsing. On the other hand, a cheap untreated softwood bench can fail faster than a well-finished metal bench. So material grade matters just as much as material type.
For coastal outdoor furniture, I follow a few practical rules. Rinse benches with fresh water every few weeks during dry, breezy weather to remove salt film before it can do damage. Touch up scratches on metal immediately because scratches expose bare metal to salt air. Choose dense, naturally weather-resistant woods for wooden benches, or use a high-quality exterior sealer on softer woods. For metal benches near the coast, look for aluminum, marine-grade stainless steel, or hot-dip galvanized steel with a strong powder coat. Keep wooden benches slightly off the ground and allow air circulation so the underside does not stay damp.
So, will salt air damage a metal outdoor bench faster than a wooden park bench? In the typical budget-to-mid-range comparison, yes—it usually will. But if you choose marine-grade metal or a dense hardwood, the difference shrinks, and maintenance matters more than the material label. By the coast, the most important habit is not simply choosing metal over wood or wood over metal—it is planning for salt exposure and keeping the salt rinsed off.