The defects which are commonly found in paint work are as follow.
Formation of bubbles like shapes on the painted surface is known as blistering. The primary cause of this defect is water vapor. When water vapor trapped under the paint layer, it creates bubbles under the film of paint.
Formation of dull patches on the painted surface is known as blooming. The primary cause of this defect is poor quality of paint and improper ventilation.
When there is a gradual loss of colour from the pained surface, it is known as fading. The main cause of this defect is the reaction of sunlight on pigments of paint.
In this type of defect, some portion of the paint film is not sticked properly with the surface; resulting flaking off of the paint layer. This is cause due to poor adhesion between paint and the surface to be painted.
Presence of glossy patches on the painted surface is known as flashing. The cause of this defect is mainly due to poor workmanship, cheap paint or weather actions.
If the thickness of the final coat of paint becomes very thin, the background can be seen clearly. This is known as grinning. Poor workmanship is the main cause of this defect.
This type of defect is seen when the surface to be painted is very smooth. In case of smooth surface the paint runs back and leaves small areas of surface uncovered.
This type of defect is more prominent when a thick layer of paint is applied on a vertical or inclined surface.
Formation of soap patches on the painted surface is termed as saponification. Chemical action of alkalis is the cause of this defect.
This type of defect is more prominent when a thick layer of paint is applied on a horizontal surface.