Choosing the right material for an outdoor bench by the sea is crucial. Salt spray is incredibly corrosive, quickly rusting metals and degrading unsuitable woods. Your best bets are materials engineered for marine environments.
First, consider Marine-Grade Aluminum. It's lightweight, incredibly strong, and naturally rust-proof. The powder-coated finish provides an extra layer of protection against salt. It requires minimal upkeep—just an occasional rinse with fresh water.
Next, Teak Wood is a classic, premium choice. Its natural oils repel water and resist rot, insects, and salt damage. It weathers to a beautiful silvery-gray patina without treatment. While expensive, its longevity by the coast is unmatched.
For a modern, eco-friendly option, look to High-Density Polyethylene (HDPE) Lumber. Made from recycled plastics, it's impervious to salt, moisture, rot, and insects. It won't splinter, crack, or fade severely and needs no painting or sealing.
Stainless Steel (Grade 316) is another excellent, though often costlier, option. Known as "marine-grade stainless," it contains molybdenum for superior resistance to chloride corrosion from salt.
Avoid ordinary steel, wrought iron (unless with a superb, maintained finish), and untreated softwoods like pine. They will succumb to rust and rot rapidly in this harsh setting.
Ultimately, for a blend of durability, low maintenance, and coastal resilience, marine-grade aluminum, teak, and HDPE stand out as the top-tier materials for your seaside bench, ensuring beauty and function for years to come.