Another common symptom of a failed paint coat is when the paint peels off from the surface. The paint may commonly appear to curl and flake from the work surface for a number of reasons. Most commonly, the peeling occurs because of poor paint adhesion, due to improper prep work or lack of primer.
Before any new paint is applied to the exterior of your home, the surface must have the necessary roughness for the paint to grip to. Sanding and/or applying a layer of primer is sufficient to provide this roughness.
This condition most commonly occurs on painted masonry surfaces, such as brick or concrete. Efflorescence appears as crusty white salt deposits emerging through the paint film. This situation transpires when salts in the brick or concrete become dissolved with water, and then attach to the surface as the water evaporates.
Some common causes of paint efflorescence include moisture emanating from indoors, inadequately waterproofed below-ground walls, and poor surface preparation. If basement walls are not adequately waterproofed, ground water may penetrate the paint and induce efflorescence. Cracks in walls and other water damage are also common causes. If the concrete or mortar was not entirely cured and dried out when the paint was applied, or if prior efflorescence was not entirely removed before the last paint job, the condition may materialize.
Another common symptom of failed paint is the appearance of mildew and mold. Mildew is easily recognized as dark green, brown, or black splotches on the paint surface, and is usually found in damp, shaded areas. Mildew is actually a living fungus which feeds and grows on paint film.
Mold spores can float through the air and form new colonies where they land. Mold and mildew have been found to cause several health problems, such as chronic fatigue, sinus problems, respiration problems, sleep difficulty, and an impaired immune system.
Mildew and mold is most commonly caused by heavy moisture, poor ventilation, and lack of sunlight. A combination of these conditions will provide an ideal habitat for mold and mildew to thrive and grow. Some of the most common areas on the exterior of your home where mildew may grow include the underside of soffits, eaves, and similar shaded areas.
Paint chalking occurs as a formation of fine powder on the surface of the paint film. Chalking paint will rub off of the surface and get on to skin, clothing, etc. Chalking paint can also have a fading effect on the paint coat. Chalking is actually a natural cleanses process of paint, however, excessive film erosion can result in heavy chalking.
This problem is typically caused by the use of a poor quality paint, or the use of an interior paint on the exterior of the building. Before applying a new coat of paint, be sure to fully remove any excess chalk from the surface. Primer may also be needed.