Exterior painting presents a different set of challenges than does interior painting. Building heights, terrain and most notably weather are all factors that painting technicians must navigate in order to complete an exterior painting project. One factor that sometimes gets overlooked is extreme temperatures, especially North Carolina heat and humidity!
Many people are familiar with the old rule of only painting when the temperature is above 50 degrees. That rule no longer applies with current exterior latex paints and most high-end exterior paints may be applied to substrates with a surface temperature as low as 35 degrees. While that is obviously uncomfortable for the technician, it gives painting companies much more flexibility painting exterior projects in the fall and winter seasons.
But what about hot weather? There really isn’t a widely understood rule for how hot is too hot to paint. Most technical data sheets will only specify a “do not paint below this temperature” but not a “do not paint above this temperature” or maximum surface temperature. The ones that do may specify a maximum surface temperature of 100 degrees or in the case of a new product hoping to capitalize on hot weather painting, 120 degrees!
Not only can such temperatures be dangerous for the technicians attempting to work in them, but they also make for a less than ideal paint job. When paint is applied to a surface that is 95 degrees and above it dries almost instantly causing “flash”. Meaning everywhere the paint is lapped it is like another coat creating excessive lap marks and may cause the paint to cure improperly and fail to bond to the substate which may in turn lead to bubbling and or peeling and ultimately shortens the life of the paint film.
They are several methods to alleviate such a situation. The first is to paint early and shorten the working day. Starting just before sunrise and stopping by about 2pm before the most extreme heat of the day can help to keep surfaces from becoming too hot to apply paint. Working in the shade is also key. Planning the painting so that if there is one side that is gets sunlight all day is painted first thing in the morning and then moving around the building following the shade can make surface temperatures significantly cooler. Finally, surfaces can be sprayed with water using a hose or pressure washer directly before painting. If the surface is hot enough the water will evaporate quite quickly lowering the temperature by up to 25 degrees.
Ideally most exterior painting would take place in spring and fall when the weather and temperatures are most conducive to a good-looking and long-lasting paint job. However, as all painters know, exterior painting is never ideal! By managing surface conditions, a fine exterior paint project can be achieved almost any time of year.
Are you ready to behold the power of paint? Schedule your free estimate here!