Adhesion Patch Test For Paint Compatibility Perform an adhesion patch test before repainting to ensure paint compatibility for exterior house painting and avoid adhesion failure. This paragraph explains how to identify existing paint types, conduct a small adhesion patch or cross hatch tape test, and when to remove failing coatings to a sound substrate before spot-priming. Learn best practices like using a primer compatible with the existing film, pairing primer and topcoat from the same manufac