The long-term durability provided by galvanizing is achieved at relatively low environmental burden in terms of energy and other globally relevant impacts, especially when compared to the energy value of the steel it is protecting.
Attention to durability of steel structures and components has important environmental, economic and social consequences. Some of these are less obvious than others.
Several studies have demonstrated the high economic and environmental costs associated with the repeated maintenance painting of steel structures. These burdens can be significantly reduced by an initial investment in long-term protection.
In 2016, EGGA completed an extensive Life Cycle Inventory (LCI) study to determine average environmental burdens required to give lifetime protection for steel products. The study was carried out by Life Cycle Engineering srl (Italy) and collected detailed environmental information from 66 galvanizing plants producing over 1 million tonnes of coated steelwork in 14 countries. LCE worked closely with EGGA’s national associations to collate the sample. The sample was then carefully checked to be representative of the mix of technology used across the industry. The LCI data are fully comprehensive – covering every aspect of the galvanizing process, from raw materials to process energy and ancillary operations. EGGA’s LCI data is available, on request, to LCA professionals who are engaged in relevant life cycle studies for galvanized products.
EGGA has published an Environmental Product Declaration (EPD) for ‘Batch Hot Dip Galvanizing of Steel Products to EN ISO 1461 – European Average’.
The EPD has been generated under the International EPD System® and is verified in accordance with ISO 14025:2010 and EN 15804.
Batch galvanizing is most often specified early in the design of steel components and structures with the coating application being sub-contracted much later in the supply process. For this reason, a sector-based EPD is the most informative approach for architects and designers when considering environmental information. Environmental burdens of the galvanized coating are separated from that of the steel plate – to demonstrate that the additional burden of providing lifelong protection for steel components is extremely small.
Statement on Existing EPD Status
The formal expiry date for the existing EGGA EPD was September 2021 and this was extended to October 2022 due to data collection delays during the COVID period. A new update of the EGGA EPD has since been delayed by the ongoing revision of the Product Category Rules for ‘Corrosion Protection of Fabricated Steel Products’ 2011:16 Version 2.2. However, the existing EPD remains available at the International EPD System (see link above).
The EGGA Market Development and Product Sustainability Committee considers that the technical basis of the published EPD remains representative as a sector average for the galvanizing of steel articles in Europe. We also note that any future update would likely reflect lower environmental burdens associated with (i) wider use of renewable energy across the sector (ii) lower embodied energy burdens associated with the availability of zinc metal with lower embodied carbon and (iii) other improvements in environmental performance. The use of the existing EPD is therefore a worse case pending the ongoing update. EGGA is not aware of a more representative and appropriate dataset for batch hot dip galvanizing in a wide range of applications and locations.
An updated EPD is scheduled alongside the revision of PCR 2011:16 during 2025. Meanwhile, we therefore recommend using the existing EPD data in building assessments until the update is completed according to a revised PCR
Articles and Useful Documents
Case Study 1: LCA Example – Balcony Structures
Case Study 2: LCA Example – Car Parks
Case Study 3: Durability – Bridge in the Netherlands after 60 Years
Case Study 4: Durability – Marina in Switzerland after 38 Years
Case Study 5: The Bridge of Sustainability
‘Life cycle studies show galvanized steel lighting columns have best environmental credentials’, Gert-Jan Vroege, Search Consultancy B.V., the Netherlands, Hot Dip Galvanizing Magazine, Issue 03/2014
‘A Life Cycle Approach to Comparing Galvanized Steel with Aluminium for Lighting Poles’, Gert-Jan Vroege, Search Consultancy B.V., the Netherlands, EGGA Assembly 2014
