How Long Does HDG Last?

Hot-dip galvanising (HDG) provides steel structures with an indefatigable barrier against corrosion in even the harshest and most demanding environments, guaranteeing decades of maintenance-free longevity in any environment. While its corrosion resistance varies according to environmental conditions, HDG typically exhibits a corrosion rate of approximately 1/30th of the corrosion rate of uncoated steel in similar settings.

As galvanised coating consumption rate increases during its initial years of service, it can provide valuable insights for projecting a conservative estimate of its remaining life before needing maintenance. Over time, a fascinating phenomenon emerges: as zinc corrosion products accumulate on their surface, they form an adhesive protective layer which usually remains relatively insoluble under most environmental conditions and reduces corrosion rates overall, prolonging the galvanised coating’s longevity further.

Zinc coatings’ corrosion resistance is determined primarily by their thickness; however, environmental conditions also play a factor. Each environment can impact hot-dip galvanising differently due to specific corrosion variables that require consideration during hot-dip galvanising processes. Planning and budgeting accordingly for required maintenance ensure longevity for zinc coatings.

Hot-dip galvanised steel products are resilient enough to withstand exposure to atmospheric elements such as, UV rays, snowfall and other forms of weather; being submerged in water bodies; being embedded into the soil or concrete structures; or in various other environments; without incurring significant corrosion and fulfilling their intended design life spans.