Cleaning

• Unless your vinyl siding is new, it is likely marred with a dusty, chalky coating. This coating greatly inhibits primer adhesion, resulting in eventual paint failure. You must use a pressure washer to eliminate this coating, or you will end up with extensive paint failure. Point the washer at a downward angle to prevent water from collecting underneath the siding.
  
  

Sanding

• Vinyl siding is not suitable for primer and paint adhesion. You can enhance surface adhesion by abrading the siding with 180-grit sandpaper. Once the vinyl feels slightly rough to the touch, it is ready to accept a coat of primer.
  
  

Application

• Acrylic latex primer is appropriate for vinyl siding, because its elasticity allows for contracting and expanding in varying temperatures. Acrylic latex paint is best suited for vinyl siding for the same reason. Ordinary latex paint is not as elastic as acrylic latex and may crack in extreme temperatures.