Generally, you should be ready to give the current coat about 2-4 hours to dry. While this estimate can differ from one type of paint to another, even from one coat to another, it usually doesn’t vary too much and is a great guideline to use. So let’s dive into why this is the case and what might happen if you decide to jump the gun and get started on that next coat too soon.
The dry time for your specific painting project will depend on a couple of variables. The biggest factor in dry time is the type of paint you’re using, and another significant influence is the application method and resulting thickness of the coat.
For those using latex paint, painting with a brush will usually lead to a thicker coat, which will add to the time needed to dry. A brush will also be suitable for both smooth and textured surfaces. The first coat of brushed latex paint can take 1.5-2 hours to dry to the touch and about 5-6 hours for a second coat.
On the other hand, using a paint roller will give you a thinner and more even coat that can faster. However, a roller can often only be used on relatively smooth surfaces. When using a roller, the first coat will generally be dry to the touch inside of 90 minutes and should be ready for the second coat in 4-5 hours.
Whether applied by brush or roller, oil paints will require far longer waits. Your first coat of oil-based paint likely won’t be dry to the touch for at least 6-8 hours and will require a full 24 hours to become ready for a second coat.
Each type of paint has a different base to it, either latex or oil, which is what makes it a spreadable medium. Once you apply the paint, the base begins to evaporate, and as it does, the paint dries. The difference in dry times is primarily due to how quickly the base can evaporate, which varies by material.
Latex-based paints, sometimes referred to as water-based, have relatively quick dry times since the water can evaporate easily. However, oil-based paints have some VOCs in them (volatile organic compounds, the “oil”) that take longer to evaporate and fully dry. This is also why painting should be done in a well-ventilated area since the evaporation of the base can produce dangerous fumes.
If you don’t give the first coat enough time to dry before adding a second or third coat, you run the risk of there being too much moisture left in the base coat. This will lead to poor adhesion, which can be seen as bubbling, peeling, or failing to dry to the touch for long periods.
The biggest problem with this is that it’s unpredictable. While you might see the paint begin to bubble or slough off while you’re painting the next room, this isn’t always the case. Sometimes it can be weeks or even months before the top coat of paint becomes visibly damaged, which can lead to you having to strip and repaint the entire surface.
In a Hurry?
While there is no one, singular way to hasten paint drying, there are some things you can do to give it the best environment possible to dry. While brushing applies the thickest coat, and roller painting gives a thinner and more uniform coat, a paint sprayer will beat them both. A sprayer will apply the thinnest and most uniform coating, but you may need to rent or buy a quality sprayer.
Additionally, be sure there is enough ventilation and air circulation so that the evaporation process can continue unimpeded. Finally, if you’re really under a time crunch, you can lower the humidity and raise the temperature a few degrees to speed up the evaporation. Portable dehumidifiers can be invaluable here. Alternatively, you can set your furnace-mounted dehumidifier to 50% relative humidity or less if you can.
Gearing up to paint can be exciting, and it can make you feel like you’re in a different space, but it comes with its caveats. Patience is a virtue, so make sure you give that first coat as well as any subsequent coats ample time to dry, and you’ll have a quality paint job that should last for years.