House paint can “fail” for several reasons. This newly revised FinishLine reviews the most common causes, including:
- Wood was wet when it was painted
- Unfinished siding was exposed to several weeks of sunlight before painting
- Temperature was too cold when the wood was painted
- Wood was too hot when it was painted or was heated soon after painting
- Weather was too humid when the surface was painted
- Humidity in the house was too high during the heating season
- Wood was installed directly over foam or foil-faced insulation board
- House has no interior vapor barrier
- Wood siding was dirty
- Wood has mill glaze
- Wood has decayed (rotted)
The following tips can help prevent house paint failure (not applicable
to semitransparent or solid-color stains):
- Sand or power wash the surface of the wood if it is smooth.
- Apply paint during recommended weather conditions and temperatures.
- Treat the surface of the wood with a paintable water-repellent preservative (especially the end grain).
- Prime the surface of the wood with a stain-blocking primer.
- Install siding properly.
- Properly apply caulking material
- Apply two latex topcoats over the primer.
In the baker’s dozen of revised FinishLine publications, you will find no mention of specific commercial products. Although FPL wood experts such as Mark Knaebe can recommend specific techniques or methods for working with wood; FPL employees must refrain from recommending one product over another.