Mud Cracking

Deep, irregular cracks resembling dried mud in a dry paint film.

Possible Cause

• Paint is applied too thickly, usually over a porous surface.
• Paint is applied to thickly, to improve inherent poor hiding (coverage) of a lower quality paint.
• Paint is allowed to build up in corners of application.

Solution

Remove coating by sanding and scraping. Prime and repaint, with a premium water-based paint, and a roller with an appropriate nap length. Sanding the surface smooth before repainting with a premium water-based paint can also repair mud cracked areas. Premium quality paints have higher solids, which reduces the tendency to mud crack. They also have very good application and hiding properties, which minimises the tendency to apply paint too thickly.

Images courtesy of the Paint Quality Institute from Dow Coating Materials