Pickup: Accumulation of dirt, dust particles and/or
other debris on the paint film; may resemble mildew.
Use of a low quality paint, especially lower grades of
satin or semigloss.
Soil splashing onto siding.
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 Mildew). 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.