Steelwork coating for corrosivity categories
What it looks like
Incorrect coating specification or application for the environmental corrosivity, leading to premature corrosion and structural degradation.
Why it happens
The minimum coating thickness and number of coats for steelwork protection varies depending on the corrosivity category of the environment it will be exposed to. Different categories require specific surface preparation methods and protective coating types, with higher risk environments demanding more robust protection.
What it costs if it is missed
The minimum coating thickness and number of coats for steelwork protection varies depending on the corrosivity category of the environment it will be exposed to. Different categories require specific surface preparation methods and protective coating types, with higher risk environments demanding more robust protection.
How to inspect for it
Verify that steelwork coatings match the specified type and thickness for the relevant corrosivity category, and that surface preparation was completed as per manufacturer and design requirements.
How to prevent it
The minimum coating thickness and number of coats for steelwork protection varies depending on the corrosivity category of the environment it will be exposed to. Different categories require specific surface preparation methods and protective coating types, with higher risk environments demanding more robust protection.
Basis in regulation
BS EN ISO 12944
Read the source
Last updated 23 August 2026. This is our editorial summary of publicly available regulation and site practice, not building control approval or a warranty determination.