When painting a home, one of the first questions often asked is, “How long does oil based primer take to dry?”
While the correct time depends on the manufacturer, paint formula, and application, oil-based primer typically takes 24 hours to dry completely.
After one full day, you can apply the second coat. Of course, inside and outside temperatures, humidity, and coating thickness may also impact the drying time.
How Long Does It Take Primer to Dry in General?
In general, oil-based primer generally takes 24 hours to dry.
You can usually touch it before the day ends and not get a sticky residue on your hands, but you will want to wait the full drying time to ensure that you will not damage the paint job.
The second coat of oil-based primer will further prepare the surface for the colored paint.
Water-based primers are other popular options, the most renowned being a latex primer. Latex primer takes around 30 minutes to dry, but you will want to wait three or more hours before applying the paint on top.
Many experts still recommend waiting 12 to 24 hours before painting to guarantee complete dryness.
No matter what type of primer you use, you will want to apply it in thin layers to avoid clumps. Depending on the painting surface, you may need to brush on multiple coats.
A spray painter will atomize the primer and make sure you only apply a small layer.
Which Factors Affect Drying Time?
Numerous factors affect the drying time of primers, but primarily the temperature and humidity. Primers will dry faster in warmer locations with less humidity and slower in cooler, humid rooms.
Cold air can thicken an oil-based primer and freeze a water-based one, so try not to paint outdoors in winter.
The composition of primers affects their drying time as well.
Oil-based primers will almost always take longer to dry than water-based ones because of their material density.
General Considerations When Applying Primer
As the temperature of air increases, it can absorb more liquid and reduce humidity, which accelerates drying time. If you paint outdoors, you do not have much control over the humidity or temperature.
Cool or humid air will increase the drying time.
However, placing your primed surface indoors in a warm space with dry air will reduce the drying time. If possible, installing a dehumidifier in the painted room can speed things along.
Make sure to ventilate the room by opening windows and doors to allow fresh air to circulate as well.
Shut doors may cause you to inhale toxic paint fumes that could harm you or a loved one. Fans can also help with air circulation if the room does not have a window.
Things to Avoid
Here are some things to avoid when using oil-based primer:
- Do not apply latex paint over oil paint without using an oil-based primer. This can crack the paint and lead to unsightly walls.
- Try to eliminate all traces of loose paint before applying primer as they can damage the surface.
- Avoid priming the walls before performing a lead test.
- If you make a mistake, do not start brushing over the spot again because you can roughen the surface and leave brush marks. Instead, you should wait until the area dries completely and sand the surface until it smooths.
Tips to Apply the Primer
Following the below steps can help you apply oil-based primer flawlessly.
- Stir the primer with a traditional wooden stick to mix the oil and pigment as these components separate when the primer rests on a shelf. Keep stirring until you are sure that the mixture is homogeneous, and then stir some more.
- Pour the primer into a separate container like a plastic cup or bowl before use. This step prevents blobs of dried primer from infiltrating the unused mixture and creating drag marks and lumps on the painted surface.
- Once you have reached the bottom of the can, you will need to add mineral spirits to thin the liquid. You want the brush strokes to fade as the primer dries, but the thick primer can lay on unevenly. Thinning it slightly will make it more workable. Start with a teaspoon and increase as necessary.
- A high-quality bristle brush made for oil-based products allows you to spread the primer more evenly.
- You can gently sand any imperfections with a sanding sponge when the primer dries thoroughly.
Frequently Asked Questions
Here are some common questions concerning the time oil-based primers take to dry.
Should I Sand the Wall Before Painting?
Once you have applied the primer and waited for 24 hours for it to dry entirely, you can start sanding.
Ideally, you would wait even longer than one day, but that is the minimum period before sanding becomes safe.
Try to test a small patch after the wait to make sure you do not scratch up the primer.
You should sand the wall before painting if you notice any imperfections in the primer and want to smooth the surface.
It can make the paint coat glide on smoother and provide a fresher appearance if the wall has any dents or protrusions.
How Do I Prime Wood?
You can prime wood the same way that you prime a wall. You will still want to wait around 24 hours for an oil-based primer to dry.
The issue with wood is its absorbency. You need to apply several coats of primer to prevent the paint from seeping into the wood.
Do Any Oil-Based Primers Dry Faster?
Even then, you will still want to play it safe and wait a little longer before sanding or applying another coat.
Oil-based primers take much longer to dry than water-based ones, but they provide a smooth surface for your paint.
As long as you apply it in long, even strokes and thin coats, you will be able to prime any surface.
Ventilating the room and adding a dehumidifier can accelerate the drying process, but you will still want to ensure it is thoroughly dry before painting, sanding, or applying another coat of primer.
We wish you fun with your next paint job!