Blush or Haze with Shellac Primer

Heat is a remedy. December 1, 2009

I'm going to start priming cabinets soon with BIN primer. It says on the can to apply between 0-90 degrees, below 85% relative humidity, and to keep the substrate 15 degrees above the dew point. It's supposed to get pretty humid here tomorrow and I don't know how the primer might react to the weather. Can anybody tell me what might happen?

Forum Responses
(Finishing Forum)
From contributor J:
If you are using the pigmented version (white), don't fret - spray away. If you are using the clear version, in my experience, if the relative humidity is at or above 75% and you are moving enough air to be legal, then the shellac primer will blush or 'haze' (trap water vapor and look milky'). Heating the surface before or after spraying will mitigate the blush in that it is a condensation effect enacted by the evaporative cooling of the alcohol in the shellac.