Galvanising is designed to stop rust, not to hold paint. Its smooth, slightly waxy zinc surface gives ordinary primer almost nothing to grip, which is why a coating applied without preparation can peel away in complete sheets within a season.
Even a good-quality topcoat fails on galvanising if the surface underneath has not been treated to accept it. This is a mechanical and chemical adhesion issue, not a case of using a better brand of paint.
New galvanising sometimes needs a period of natural weathering before it will accept paint at all, or a mordant solution to etch the surface chemically where waiting is not practical. Skipping straight to primer on fresh, shiny galvanising is asking for early failure.
Once the surface will accept paint, a primer formulated for galvanised or zinc-coated steel, followed by suitable undercoat and topcoat, gives a durable result outdoors. Railings and gates in coastal locations still benefit from a system rated for that extra exposure.
Yes, but rust breaking through the zinc layer needs treating on its own before the galvanised-specific primer goes on, otherwise it bleeds through the finish.
It varies with exposure, which is why we assess the surface rather than quote a fixed number of weeks for every job.
It needs careful handling and containment, and we protect surrounding surfaces and plants before it is applied.
Send a photo of your railings or gate and we will confirm whether weathering, washing or mordant treatment applies.
Galvanised steel needs its surface treated for adhesion first, or even good paint peels away in sheets.
Speak to a Hampshire commercial decorating contractor that turns up, communicates clearly and delivers a finish that lasts.
