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Before selecting architectural metals for any project, it is first necessary to define the environment in which the building will be located.  Among the factors that must be considered are: 

• Atmospheric contaminants/pollution

• Proximity to salt water

• Nearby application of deicing salts

• Airborne abrasives (sand, soil, debris)

• Ultraviolet exposure

• Humidity range

• Externally induced fire risk (airborne sparks or brush fires)

• Frequency of maintenance on the part of the owner

As a rule, pure zinc is extremely durable, corrosion resistant and fire resistant.  When properly specified, fabricated and installed, it will last indefinitely with little maintenance in all but the most severe environments. 

In general, zinc is suitable in most environments, including those described below: 

• Moist climates, where moss, algae and fungus propagation is a problem.  These organisms will not survive in contact with zinc.

• Marine environments not subjected to airborne sand and salt spray.

Zinc, which is alloyed with copper and titanium, is appropriate for most applications.  Other grades are also available with differing mechanical properties.  Once a grade has been selected, a finish choice can be made to create the desired visual effect.  Untreated zinc is quite reflective in its initial state.  Once installed, it takes years for the surface to mature into a dull, medium gray patina.  If it is desirable to have an aged appearance upon installation, pre-weathered material that has been chemically treated to replicate years of weathering is also available.  Unlike copper, zinc does not produce undesirable runoff that can stain masonry and paving materials below.  Since it is a natural tendency for zinc to eventually look like the pre-weathered finish, scratches will blend into the surface over time.  In arid climates, either product will eventually develop a white oxide (while it is not detrimental to the performance of the material, it may not be visually desirable).