For a coastal area with salty air, the most durable type of outdoor furniture is made from materials inherently resistant to corrosion and degradation. The top contenders are cast aluminum and marine-grade polymer.
Cast Aluminum Furniture is exceptionally durable for salt air environments. High-quality aluminum frames are often finished with a thick, powder-coated layer that acts as a robust barrier against salt corrosion. It is heavy, stable in wind, and requires minimal maintenance—just occasional washing with fresh water.
Marine-Grade Polymer (HDPE) Furniture is arguably the ultimate choice. This solid material is impervious to salt, moisture, UV rays, and extreme temperatures. It won't rust, rot, peel, or splinter. Brands like Trex® and POLYWOOD® offer this furniture, which is essentially maintenance-free and can be simply cleaned with soap and water.
While stainless steel (Grade 316) is excellent, it is costly. Teak is a natural option but requires regular upkeep to maintain its appearance in harsh coastal conditions. Avoid ordinary steel, wrought iron, and low-quality materials that will quickly succumb to rust.
In conclusion, for maximum durability and minimal upkeep in salty air, invest in powder-coated cast aluminum or marine-grade polymer furniture. These materials are engineered to withstand the harsh coastal environment beautifully for decades.