Aluminium is corrosion-resistant by nature, but the visible surface — the powder coat — is what your clients touch and judge. A well-specified finish is a multi-stage system, not a single spray.
What good looks like
Start with an etched, cleaned substrate (no oils, no mill scale). Apply a zinc-rich primer where coastal exposure is expected, then a UV-stabilised polyester top coat cured at full temperature. Cheap lines skip the primer and under-bake; the result chalks within two seasons.
Specification checklist
Ask suppliers for salt-spray test hours (1,000+ for coastal), film thickness (60–80 microns), and a stated UV-stabiliser. Request a cured-sample scratch test — a proper coat resists a sharp key without flaking.
Colour that lasts
Mid-tones and textures hide minor wear better than pure whites or blacks, which show chalking fastest. For a premium, low-maintenance fleet across many sites, a restrained warm grey is the safe hero colour.
