What Does Crackled Paint on a Wall Mean?

Moisture

• Moisture can cause a number of problems with paint, including crackling. In this case, the moisture comes from the paint itself. More specifically, from the previous layer or base coat of paint applied. If this paint is not allowed to dry properly before it is painted over, the top coat will crackle. All paints list a recoat time that is the minimum time you need to wait before applying another layer of paint. This time may need to be extended, however, if the temperature is below 70 degrees Fahrenheit or the humidity is above 50 percent. Both of these conditions slow down the drying time of paints.

Incompatible Coats

• If two layers of paint are incompatible, crackling will also appear. This can occur in two ways. The first is if you paint a rigid paint over a flexible one. Oil-based enamels are not as flexible as latex paints, which is why you should never use oil-based paints over water-based ones. Alligatoring may also occur if you try to paint over a glossy surface without sanding it first. In this case, the paint has nothing to adhere to and cracks or peels.

Age

• Crackling is not always a problem on newly painted surfaces. It is also a natural occurrence with most oil-based paints. Over time, temperature fluctuations cause surfaces to expand and contract. As oil-based paints age, they lose their elasticity and become even more rigid so that when the surface expands or contracts, the paint cracks.

Correcting

• When crackling appears, your only option is to stand or scrape away the paint. Once the old paint is removed, wash the surface thoroughly to remove any dust or loose paint. You can then repaint the surface with a good quality primer followed by a top coat of paint. Don't try to paint over the crackled paint as it will only cause the new paint to fail.