Hot-dip galvanizing means dipping the finished steel in molten zinc. EN ISO 1461 is the general standard for fabricated items (ASTM A123 is the US equivalent). The minimum coating depends on how thick the steel is. Typical values for items that aren’t centrifuged:
| Steel thickness | Minimum local | Minimum average |
|---|---|---|
| 6 mm and over | 70 µm | 85 µm |
| 3 mm to under 6 mm | 55 µm | 70 µm |
| 1.5 mm to under 3 mm | 45 µm | 55 µm |
| Under 1.5 mm | 35 µm | 45 µm |
Values as published by galvanizers’ associations. Check the thickness bands against the current EN ISO 1461:2022 text. Actual coatings usually come out thicker.
Where exposure is harsh or a colour is needed, a paint system over the zinc adds life. The zinc needs proper surface prep for paint to stick, so write the full system and RAL code rather than just “painted”.
We design the steelwork for galvanizing and deal with the galvanizer for you. Related: industrial guardrails and platforms.
Answer a few questions and you get a list of what to attach, plus a summary you can send us straight away.
You can, but the weld burns off the zinc around it and that area then needs repair. It's better to finish all welding and drilling first.
Both cover hot-dip galvanizing of fabricated steel, but the thickness tables and test methods differ. Tell us which one your spec uses.
Yes. We fabricate for it, send the steel to the galvanizer, and deliver it back to you or to site.
Check the numbers against the current edition of each standard and your project spec.