Painting outside before it rains? It is important for you to know how long it takes exterior latex paint to dry before rain. When it rains, if the paint is not fully dry, the water will dissolve your paint and you’ll end up with having to repaint. The time needed for outdoor or exterior latex paint to dry before it rains will always vary depending on factors such as temperature and humidity.
How long does exterior latex paint take to dry?
Exterior latex paint, like most paints, usually takes between four and eight hours to fully dry. It is a good idea to allow for at least twelve hours of drying time before the rain starts.
If you can allow the paint to dry 24 hours before it rains, that is best. If in a high humidity environment, the paint will take much longer to dry. If you have a choice, paint an exterior surface when the humidity is low.
Humidity is a big factor with drying times. Pay attention to what type of paint, substrate, method used, and thickness is applied. Also factor in the sunlight and wind speed as each paint job will vary.
NOTE: Most exterior paints dry in a few hours but may take a few days to cure fully. Always consider the weather when painting.
What about exterior primers?
The drying time for a primer depends on many factors. Different types of primers dry at different rates. Different brands and types of latex paint can also have varying drying times. The key is to always read the package instructions for more information.
How dry or sealed the surface is that you are painting also impacts the time it takes to dry. A dry or porous surface will absorb primer more quickly, which could speed up drying time.
Weather conditions could play a role in the drying time. When painting outdoors, hot dry weather, cool temps and high humidity will all affect how quickly your paint dries. Primer and paint dries faster in hotter dry weather while colder temperatures or high humidity areas can make drying process slower. Another factor is the wind, which can speed up the drying process.
One hour after the primer is dry to the touch, light rain should not be able to penetrate the primer. The primer of an exterior paint job needs to be dry before a heavy rain or it may wash off. If it does rain before the primer is dry you will need to wait for the rain to stop, scuff the area, sand it down, and prime it once again.
What about exterior oil based primers?
An oil based primer will take a little longer to fully dry but can handle rain. If the the substrate is dry when the primer is applied then rain should not effect it 30 to 60 minutes after you apply it. Rain will slow the process of drying and might change the appearance, but it should not affect the quality of surface bonding.
In order to prolong the life of your exterior paint job, it would be best for you to have a general sense of how long it takes for paint to dry. Predicting the drying time for exterior latex paint is difficult as there are many factors. There are general rules for estimating how long your fresh paint job should last before it becomes damaged as a result of exposure to rain.
One popular question asked of paint experts is how long does exterior latex paint need to dry before it can be exposed to adverse weather conditions such as rain or snow. If you live in a region where temperatures fluctuate, rain comes unexpected, or high humidity, then knowing when and what time to paint with exterior latex paint is important.
Have questions about painting with exterior paints? Please leave a comment below and someone can assist you.