Painting steel near the sea

In Visakhapatnam, salt in the air reaches every steel structure within a few kilometres of the coast. Untreated steel starts to rust within weeks, and a poorly painted shed can need repainting in three years.

The most important step is the one you never see: surface preparation. We shot-blast every member to remove mill scale and rust down to bare metal, which gives the primer a rough surface to grip. Paint applied over mill scale looks fine for a year and then peels off in sheets.

After blasting, we apply a zinc-rich or epoxy primer within hours, before the steel can flash-rust, followed by an intermediate coat and a polyurethane finish for structures exposed to sun and salt. We measure dry film thickness at several points on each piece.

For platforms and handrails right on the coast, hot-dip galvanising is often worth the extra cost. Tell us how far your site is from the sea, and we will suggest a paint system and show you its expected life.