Winters can be fairly mild in most parts of California, but the state still sees temperatures drop down to chilly, or even freezing. How does this type of environment affect the painting process? There are potential problems for commercial painting contractors whenever the temperature falls to around 40 degrees or less.
What happens to cold paint?
When the temperature is sluggish, so is paint. Cold can thicken or freeze the carriers—the water used in water-based formulas, or the solvent contained in solvent-based paints. This means a slowdown in the drying and curing process. If a commercial painting contractor doesn’t allow extra time for drying between coats in cold weather, the paint can blister and bubble, or may fail to adhere to the coating beneath.
Another problem during cold weather is moisture. Cool temperatures cause dew to form on the substrate or the surface of the paint that has already been applied—while cold or freezing weather produces frost. Both of these forms of moisture can lead to premature paint failure or erosion.
Cold weather workarounds
Skilled commercial painting contractors will use various methods to ensure that exterior paint is properly applied and cured during cold weather. The most common solution is to avoid painting in the early mornings and evenings, when the temperatures are lowest. While painters “follow the shade” in the summer, the opposite rule is used in winter. Following the sun, or painting in direct sunlight whenever possible, helps to dry the paint at normal rates.
It’s also important for contractors to have a strong working knowledge of paint types and substrates. Not all kinds of paint are rated for cold-weather application, but some can be used in temperatures as low as 35 degrees. The contractor should also measure the moisture content of the substrate, and prepare the surface thoroughly with the correct primer.