Duplex systems, painting or powder coating over hot-dip galvanizing, have steadily grown in popularity over the last decade. Specifiers often utilize duplex systems on projects where corrosion protection is pertinent, but aesthetics, namely color selection, is also a high priority. The combination of hot-dip galvanizing and paint ensures the designer does not have to sacrifice either desire. But to consider a duplex system as merely a cosmetic extra to the durability of hot-dip galvanizing is a gross misrepresentation. In addition to visual benefits, duplex systems provide cost savings and extended service life. To calculate how you can save money over the life of your next project by utilizing a duplex system, visit the AGA life-cycle cost calculator at lccc.galvanizeit.org. 

This handout details the life-cycle savings of utilizing a duplex system of paint over galvanized steel. It explains how duplex systems work and focuses on the maintenance cycle, life-cycle, and return on investment of this type of corrosion protection system. (2 pages, revised in 2012)