The main differences lie in weight, appearance, and surface finish. Aluminum is lightweight and can be powder-coated in a variety of colors, while stainless steel is heavier and has a distinct metallic look. Both are durable for outdoor use when the right materials and construction are used. Aluminum forms a protective oxide layer and is further protected by the coating.
For stainless steel, the grade should be selected based on the environment—especially near the ocean—and the surface should be cleaned as needed. The stability of the railing depends on the entire system, not just the material of the posts. Aluminum is a good choice when you want a specific color, while stainless steel is best when the metal is meant to be part of the design.
