Semi-gloss has a high amount of sheen (or gloss) on its formula, giving the paint a glossy finish. So, how long does semi-gloss take to dry?
It takes semi-gloss 2 hours to dry between coats and 12-24 hours to dry fully (cure). So, you must wait 2 hours before you apply another coat over it and 24 hours before you use the painted surface.
However, the dry time depends on the room temperature, humidity, weather, and the number of coats applied. For example, the paint takes 2 times longer to dry in humid conditions.
How Long Does Semi-Gloss Paint Take to Dry Between Coats?
It takes semi-gloss paint 2 hours to dry between coats. However, water-based semi-gloss dries faster than oil-based semi-gloss. That’s because water-based brands have less gloss on their formula and use water as their solvent. Since water evaporates fast, the water-based type will dry faster.
If you re-coat too soon, the finish will turn sticky or tacky. That’s because the paint coat hasn’t dried yet, and if you apply a new coat, none of the coats will dry. This leads to a sticky and tacky finish. If this happens, you must remove the entire finish and re-apply it.
Semi-gloss will dry faster outdoors than indoors during summer, and slower outdoors than indoors during winter. On average, it takes semi-gloss paint 1 hour to dry enough for a re-coat outdoors during summer. The paint dries faster outdoors than indoors because the coating is exposed to outdoor elements (heat and dry air) that make it dry faster.
During winter, the semi-gloss paint takes longer to dry outdoors because of the increased moisture levels and other weather elements.
You must sand between each coat of semi-gloss paint (except for the final). That’s because semi-gloss forms a glossy finish that repels liquid. So, if you apply another coat over it, the coat won’t stick over the glossy finish. However, sanding will remove the glossy layer of the paint and allow the next coat to stick.
If you don’t sand between semi-gloss coats, the old coat will bleed-through the new paint coat and stain the finish. Also, the paint will have poor adhesion, so the finish will peel off eventually.
Related Read: Gloss Paint Dry Time?
How Long Does Semi-Gloss Paint Take to Cure (Fully Dry)?
It takes semi-gloss paint 12-24 hours to cure (dry fully). When the paint’s solvent evaporates and the particles harden and become compact, the paint has cured. Once the paint is cured, you can use the surface and wash it without the paint coming off.
If you use or clean the surface before the paint cures, the finish will get removed. That’s because the paint particles aren’t compact and hard enough to withstand water and usage.
Also, once the semi-gloss paint cures, the finish will have a glossy appearance that repels water, moisture, and scratches. If you want to paint over a cured semi-gloss paint, you must sand the glossy finish or use a topical paint.
How Long Must Semi-Gloss Paint Dry Before Sealing it?
Semi-gloss paint must dry for 12-24 hours before sealing it. In other words, the paint must dry fully (cure) before you can seal it.
If you seal semi-gloss paint too soon, the finish will become sticky. That’s because when you seal the paint, you prevent moisture (or oils) from evaporating from the coating. If the paint’s solvent hasn’t evaporated yet, the sealer will prevent it from evaporating, so the paint won’t dry and will remain wet.
Also, if you apply the sealer before the paint coating oxidizes, the finish will crack. That’s because, during oxidation, the paint coating hardens and compacts. But, if you stop the oxidization process with the sealer, the coating won’t harden or be compact enough and will crack.
How To Make Semi-Gloss Paint Dry Faster?
Since the paint dries through evaporation, you must increase the evaporation rate to speed up the drying time. To increase the evaporation rate, you must increase the air circulation and heat around the coating.
Here’s how to do it:
1. Use a Hairdryer
To increase the evaporation rate of the solvent, use a hairdryer. The hairdryer will produce heat around the paint coating and increase the evaporation rate. For this method, you must move the hairdryer over the paint coating for a few minutes.
Here is a guide:
- Turn on the hairdryer.
- Use a medium temperature.
- Move the hairdryer around the paint coating for 5 minutes.
- Wait 5 minutes.
- Move the hairdryer around the paint coating for another 5 minutes.
- Turn off the hairdryer and allow the paint to dry.
You shouldn’t completely dry the paint using a hairdryer. That’s because the paint will dry too fast, and the paint particles won’t have enough time to harden or compact. If semi-gloss paint dries too fast, the glossy layer will be soft and won’t withstand water or moisture.
2. Using a Dehumidifier
If the humidity levels are high, the paint takes longer to dry because there’s a lot of moisture (or water) in the room. The high amount of moisture prevents the paint from drying fast.
A dehumidifier will decrease the humidity levels and help the paint to dry faster. The dehumidifier will suck (pull) the moisture in the air and replace it with dry air, so the semi-gloss paint dries faster.
Here is a guide:
- Open all vents.
- Turn on the dehumidifier.
- Set the dehumidifier between 30 and 50%.
- Leave the dehumidifier to work until the paint dries.
3. Use a Paint Dryer
A paint dryer is an additive that can be added to the paint before applying it, making it dry faster. The paint dryer will speed up the autoxidation process and make semi-gloss paint dry faster.
Here’s how to use it:
- Open the paint dryer.
- Add the paint dryer to the semi-gloss paint.
- Stir the mixture.
- Test the paint to check if it has a consistent color.
- Apply the paint.
Note: You must add the paint dryer just before the paint is applied (5 minutes before applying). Also, you can only use one paint dryer in the mixture.
Here are some other drying speed-up tips:
- Allow proper circulation while applying the paint.
- Apply light coats.
- Thin the paint before applying it.
- Use a paint sprayer.
Why Isn’t Semi-Gloss Paint Drying?
Semi-gloss paint isn’t drying for the following reasons.
1. You Applied Thick Coats
If you apply a thick semi-gloss coating, the paint will take longer to dry because the evaporation and oxidization rate will be slower. So, you must thin the paint before applying it.
2. You Didn’t Sand Between Coats
If you don’t sand off the glossy finish before applying a new coating, the new paint coating won’t stick or dry. So, sand between coats of semi-gloss paint with fine-grit sandpaper before re-coating.
3. The Temperature is Too Low
During low or moist temperatures, the paint takes longer to dry. For example, if you apply paint when the temperature is lower than 40 degrees (F), the paint will take 2 times more than usual to dry. So, only apply paint when the temperature is between 50-90 degrees (F).
4. The Surface Is Wet
If you apply paint over a wet surface, the paint won’t dry because of the moisture on the surface. Therefore, you must clean and dry the surface before applying paint. Optionally, you can use a stain-blocking primer before applying paint.
How To Know if Semi-Gloss Paint has Dried?
To know if semi-gloss paint has dried, do the following.
- Sand – If the paint has dried, you can sand it without the sandpaper clogging into the wet glossy coat. The sandpaper will move freely and smoothly over a dried paint coating.
- Hard Coating – Once the paint dries, the top layer will be hard and slick. If the top layer feels damp, cool, wet, or sticky, the paint hasn’t dried yet.
- Water – Once semi-gloss paint dries, the glossy layer will be moisture-resistant and won’t allow water to penetrate its coating. So, apply a few drops of water over the finish. If the water penetrates the finish, the paint hasn’t dried yet. If it doesn’t penetrate and stays on top of the paint, it has dried.
- Cleaning – To know if the paint is fully dry, clean it. If the paint color comes off after cleaning, the paint hasn’t dried yet. If the paint color doesn’t come off, the paint has dried.
- Glossy Finish – When the semi-gloss paint dries, the finish will have a glossy and reflective appearance. If the paint isn’t dry enough, the surface will look wet and not glossy.
It takes semi-gloss paint 2 hours to dry enough for a re-coat and 12-24 hours to dry fully (cure). The semi-gloss dry time depends on the humidity levels, room temperature, the thickness of the coat, and the number of coats.
To make semi-gloss paint dry faster, use a hairdryer or dehumidifier, or apply paint dryer additives. You can also speed up the drying time by increasing the evaporation and oxidization rate.