Dirt Pickup

Accumulation of dirt, dust particles and/or other debris on the paint film; may resemble mildew.

Possible Cause

• Use of a low quality paint.
• Soil splashing onto the surface.
• Air pollution, car exhaust and flying dust collection on house body and horizontal trim.

Solution

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 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.

Images courtesy of the Paint Quality Institute from Dow Coating Materials