The paint on a galvanized surface – think metal doors, garages, roofs, gutters, downspouts and fascia – has lost its adhesion and is starting to lift, crack and peel.

• If you're working with a painted galvanized metal surface experiencing peeling, we recommend removing all the peeling paint before repainting. Painting over the damaged area may seem like an easy fix, but this could affect the paint's adhesion and leave an unsightly texture.
• To remove the peeling or cracked paint, apply chemical stripper (be sure to follow all packaging instructions), wait a few minutes until you see the paint bubbling off, then use a scraper to chip off the paint. Prime your fresh surface before adding a fresh coat of paint.
• If you're working with a new or unpainted galvanized metal surface, to prevent paint from peeling off galvanized metal, the protective layer of oil or passivator must be completely removed. Typically cleaning with a water-soluble agent will remove the oily residue. However, passivator will not be affected. This can be easily confirmed by cleaning a small test area with a water-based or solvent-based cleaner. Once that area is dry, test the clean galvanized area with a copper sulfate solution. If the galvanized surface does not turn black, the passivator remains on the surface. This must be removed by SSPC-SP7 in order to coat the substrate.
• Most hydrocarbon solvents, including mineral spirits, leave a thin layer of residue that leads to adhesion failure of the paint film. Instead, use a water-based cleaner or degreaser to clean a galvanized surface. Most acrylic coatings will adhere directly to cleaned galvanized metal.
• A weathered galvanized surface can develop a layer of white rust, which must be removed to ensure good coating adhesion. Try removing white rust with a wire brush or scrubbing with a stiff brush or abrasive pad. Add primer to bare steel the same day it is cleaned. Severely rusted gutters should be replaced.