How to Fix Paint Blocking

What Is Paint Blocking?

Paint blocking happens when a coat is painted on top of another fresh coat and the paint sticks to itself. This undesirable adhesion leaves bare patches on the painted surface.

What Causes It?

  • Not allowing sufficient time for the paint to dry before closing doors or windows.
  • Using a paint with low block resistance – when two painted surfaces touch, the paint tends to adhere to itself.

Solutions for Paint Blocking

  • Paint with an oil-base coating or use a high quality semi-gloss or gloss latex paint with good block resistance.
  • Remove all loose paint by scraping or other methods, and sand the surface to smooth out any rough edges. Wash away all surface contamination, rinse thoroughly and allow to dry. Glossy surfaces should be sanded until dull.
  • Prime as needed and add topcoat. Follow paint label instructions regarding dry times.
  • Application of talcum powder, wax, or soap may temporarily relieve blocking.

Paint Blocking Repair Products

Interior Repairs

If you're working on a wood door or trim, remove any paint with adhesion issues, then apply Premium Wall & Wood Primer. Once dry, add a fresh coat of ProClassic® Interior Waterbased Acrylic-Alkyd.

Exterior Repairs

For exterior wood surfaces start with Exterior Latex Wood Primer and finish your project with SuperPaint® Exterior Acrylic Latex.