In the context of painting, term used to describe poor adhesion of paint film.
As with blistering, moisture beneath the paint or varnish film is a frequent cause of flaking as is the application of paint to a powdery or friable surfaces and previous coatings. Dirt, oil, grease and polish residues on the surface impair adhesion and may result in flaking.

Excessive movement of the substrate, (e.g. at joints in woodwork), may impose stresses on the paint film causing cracking and untimely flaking.

Small areas of flaking paint can often be dealt with by removing the loose material back to a firm edge, touching-in and bringing forward as necessary, then recoating. If the flaking is extensive, or the overall adhesion of the system is doubtful, the surface should be stripped completely before repainting.