Now that you have a firm understanding of environmental and economic factors of sustainable development, let’s examine how your steel corrosion protection system affects both life-cycle assessment (LCA) and life-cycle cost (LCC).
Although the LCI and LCA studies conducted by IZA, Five Winds, and PE International focused on hot-dip galvanizing, applying common knowledge about paint systems, the following can be inferred:
- Steel, with its high recyclability and low environmental impact, is the primary component in the LCA of both galvanized and painted steel.
- Hot-dip galvanizing has less environmental impact than paint during the use phase, as HDG requires no maintenance.
- At end-of-life, the zinc of the galvanized coating is recycled, making HDG 100% recyclable, while paint coatings enter the permanent waste stream or create emissions.
Although the mass of the coating, whether galvanizing or paint, may seem minimal compared to that of the steel, when you consider entire structures utilizing thousands or even millions of kilograms of steel, the importance of the additional environmental impact produced by the coating is more evident. Additionally, just as continual maintenance of paint coatings adds environmental impact, it also adds economic impact.
To highlight the difference the coating has on the overall environmental and economic impact, consider the following case studies. The balcony and parking structures case studies utilize published environmental data, and to correlate economic with environmental impact, LCC analyses were run on the same structures with the automated online calculator at galvanizeit.org/galvanizingcost.*
*Some logical assumptions about the mix of the steel products, paint system and application used, etc. were made when the information was unavailable.