How to Identify, Fix, and Prevent Surfactant Leaching
Despite its name and appearance, surfactant leaching is an aesthetic concern, and not harmful to the paint or the surface it is on.
Surfactants are necessary water-soluble ingredients of latex paint. These water-soluble components migrate over time to the surface of the paint. When newly applied latex paint is exposed to high moisture or humidity while it’s drying and/or curing, surfactants can rise prematurely to the film’s surface, producing a residue or splotches. This residue can be sticky, discoloured, glossy or soapy in appearance.
Surfactant leaching frequently shows up in bathrooms and other humid environments on ceilings or walls. It is important to note that the discolouration from surfactant leaching is not the same as water stains or spots and should not be treated as such.
What Causes Surfactant Leaching?
- Paint drying in cool, humid conditions—common during early fall when frost can form overnight
- Condensed moisture—common on outdoor surfaces and in bathrooms
- Deeper tints—common when using deeper colour paints tinted with universal colorants which contain extra surfactants
How to Fix Surfactant Leaching
- Do not paint over stains
- Rinse the surface with water or wipe with a damp cloth as soon as you notice stains
- On exterior surfaces, normal weathering will usually remove surfactant stains naturally
