THE BEST MATERIALS FOR EXTERIOR RAILING PROJECTS
From a scientific standpoint resisting corrosion is preventing iron molecules from reacting with oxygen and water resulting in what is commonly called “rust”. Corrosion resistance should be one of the largest deciding factors when we choose an exterior railing system. Oxidizing and corrosion are not one and the same; one is a film vs. a complete degradation of the metal itself. So what are the best metals to consider when we have harsh environments like sun, salt and water?
There are four basic types of metals that fit into what we consider a “corrosion resistant” category:
Aluminum is a lightweight and popular choice for the aircraft, car and building materials industries. This metal contains almost no iron; thus resulting in spectacular corrosion resistance. It does however have a potential to oxidize over time, forming a film on the surface. Although the film may not be the desired aesthetic, it does not negatively affect the durability of the metal.
Stainless Steel comes in different grades like 18-8, 304 and 316. Each grade of stainless contains a mix of elements. The higher the grade of stainless steel, the lower the amount of iron will be contained in the mix. Chromium, nickel and molybdenum also add to the corrosion resistance. Stainless steel is heavier and stronger than aluminum considering a like for like size comparison. Railing posts made from stainless steel are preferred for constructing stainless steel cable railings because like metals offer the best corrosion resistance.
Copper and Brass contain little to no presence of iron in the metals. They do not typically rust but do tend to oxidize and “patina” over time. This actually protects the metal from corrosion but it is a matter of preference when it comes to the aesthetic. Decorative exterior statues and/or garden art pieces, plumbing fixtures and some graspable handrails are fabricated using these metals. We do not see them commonly used for structural purposes like railing posts, support beams, etc.
Galvanized Steel is very corrosion resistant when compared to regular mild steel. Galvanizing is a zinc coating applied to steel that prevents oxygen and water from reacting directly with the steel. Galvanized steel works excellent in non salt spray environments , but it will eventually corrode when exposed to marine environments. We see a lot of galvanized material used as guardrails in commercial applications because the cost of galvanized steel is typically lower than stainless and aluminum.
San Diego Cable Railings fabricates cable railings and glass railing systems using corrosion resistant metals like galvanized, stainless steel and aluminum. If you are wondering which material is right for your application, or you would like a quote for an extremely corrosion resistant railing system; give us a call or visit the quote request page.
