Accumulation of dirt, dust particles and/or other debris on the paint film; may resemble mildew.
Use of low quality paint
Soil splashing onto the substrate
Air pollution, car exhaust and flying dust collecting on house body and horizontal trim
Wash off all surface dirt before priming and painting. If unsure whether the problem is dirt or mildew, conduct a simple spot-test (see Mould).
Clean off dirt with a scrub brush and detergent solution, followed by a thorough rinsing with a garden hose. Heavier dirt accumulations may require the use of a power washer.
While dirt pickup can't be eliminated entirely, top quality exterior latex paints typically offer superior dirt pickup resistance and washability. Also, higher gloss paints are more resistant to dirt pickup than flat paints, which are more porous and can more easily entrap dirt. Dulux recommends the use of Dulux Weathershield® Gloss for exterior surfaces.
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 ageing paint solvent-based enamels.
Wrinkling is a term to describe a rough, crinkled paint surface, which occurs when uncured paint forms a 'skin'.
Tannin staining is the brownish or tan discoloration on a painted surface due to migration of tannins from the substrate through the paint film.