Surfactant leaching appears most often as a thick, brown syrupy deposit, though occasionally it assumes a white, crystalline form. It is an ingredient in all latex paints.

What Causes It?
When surfactant leaches from dried film, it dissipates in small amounts. Normal weathering removes it from exterior surfaces. But under certain conditions, such as low temperatures or on surfaces with condensed moisture, it can occur rapidly and build up. It can occur on both exterior surfaces and interiors, such as bathrooms or other areas where moisture condenses on walls. In these instances, it will appear as a clear, amber, glossy rundown.

How to Solve It
On exterior surfaces, normal weathering will usually remove any visible surfactant leaching. On exteriors protected from the elements, however, it can accumulate. To remove buildup, use a garden hose to spray it with a fine mist, or rub it lightly with a wet cloth. Often, the best solution is simply to allow the weather to remove it naturally, as surfactants will cause no harm to walls or other surfaces. They must be removed, however, before starting any painting project. Note: Images provided by The Rohm & Hass Paint Quality Institute.