How Weather Affects Paint

In an earlier post I wrote about the difference between drying and curing in reference to paints. Now to bore you even more we'll go over the factors that affect these processes, these factors are, Temperature, Air Movement, Relative Humidity, and Dew Point. Each of these factors affect the drying and curing differently and should be taken into account when applying both oil and latex paints.

The Sun in ultraviolet.  Click for more wavelengths   

 Temperature can be a big factor in the drying and curing process. With oil paints high temperatures, generally above 95 F surface temperature, will lower the viscosity, while low temps, usually below 45 F, will increase viscosity. Latex is affect differently, high temps will interfere with surface bonding, while low temps tend to limit coalescence. Air Movement also affect oils and latex paint differently. Increased air movement will cause oil paints to dry quicker and will speed the degradation of odors. With latex, too much air movement may result in flash drying, causing the paint to crater. Next up is Relative Humidity. For oil paints, high humidity may lower the sheen and cause color shift. With latex, high humidity will increase the drying time, while low humidity may cause poor surface adhesion. Dew Point is another major and an often overlooked factor of drying and curing. If the temperature of the air is lower than the dew point of the substrate, the presence of moisture will affect adhesion, drying time, color, and sheen (or gloss). This is true for both oil and latex paint.

 Weather is just one factor in creating the perfect finish. Other factors include, application method, surface preparation, product, and tool quality, all will affect on the surface finish. All of these factors are taken into account for every project I do. To get the best possible finish give me a call and I'll be glad to warm up your interior spaces.

by Jeff Hartford