Alligatoring is the patterned cracking in the surface of the paint film resembling the
regular scales of an alligator.

Possible cause

  • The application of an extremely hard, rigid coating (like a solvent-based enamel) over a more flexible coating, like a water-based primer
  • Applying your topcoat before the undercoat is dry
  • The natural aging of oil-based paints as outdoor temperatures fluctuate. The constant expansion and contraction of the paint based on the temperature can result in a loss of paint film elasticity



Old paint should be completely removed by scraping and sanding the
surface; a heat gun can be used to speed work on large surfaces, but take care to avoid igniting paint or substrate.

The surface should be primed with a high quality water-based primer and then painted with a top quality exterior water-based paint. Dulux recommends Dulux Weathershield® for a premium exterior paint.

More problem solving advice

When droplets appear on acrylic paint

Have you noticed small droplets appearing on your fresh coat of acrylic paint? Don't panic – it’s a normal part of the curing process. Find out more.


Yellowing describes the development of a yellow cast in aging paint solvent-based enamels. Find out more.


Wrinkling is a term used to describe a rough, crinkled paint surface occurring when paint forms a 'skin'. Find out more.

Tannin staining

Tannin staining is the brownish or tan discoloration on the paint surface due to migration of tannins from the substrate through the paint film. Find out more.