Copper Availability and Attributes

November 13, 2020

Basics of copper

  • Natural metal family of materials which develops patina naturally over time
  • Has been used for centuries
  • Ability to form complex shapes due to malleability
  • Prestigious appearance
  • Durable and corrosion resistant
  • Long lasting metal requiring minimal maintenance
  • Low thermal expansion values falls in between aluminum and steel
  • May be soldered

Copper and sustainability

  • Due to its value, copper roofing and wall cladding doesn’t end up in landfills, but is salvaged and recycled
  • Copper is 100% recyclable
  • Can be perpetually recycled without loss of performance or qualities

Copper facts

  • 16 oz Copper > 24 ga> .022” thickness
  • 20 oz Copper > 22 ga > .027” thickness

Patina finish – natural

  • The natural weathering of copper to the characteristic bluegreen or gray-green patina is a direct consequence of the mild corrosive attack of airborne sulfur compounds.
    • In industrial and seacoast atmospheres, the natural patina generally forms in five to seven years
    • In rural atmospheres, it may not fully patina until 10 to 15 years, or longer
    • In arid desert environments, patina formation may never occur and the copper surface may weather to a dark brown or bronze color

Pre-patinated finish – factory

  • Copper mills have developed pre-patinated (aka preoxidized) copper sheet products due to requests from the architectural community
  • The patina is a chemical conversion process whereby the top molecular surface of the copper sheet is enhanced and forced to produce a natural patina
  • It is very important to have physical samples when choosing a color
  • Some pre-patinated sheets have a variation in their color


  • Gloves should be worn when handling copper, as oils from fingerprints can be quite visible on that material
  • Copper specific training for contractors is highly recommended
    • Copper Development Association offers programs
  • Refer to building panel transit, jobsite handling and storage procedures document on the ATAS website