A significant factor to consider in choosing chemical compounds, especially volatile organic compounds, is their drying rate. Polyurethane is formed by dissolving polyurethane resin in a liquid solvent. It is one of the most used compounds because of its ability to furnish wood. Carpenters and wood engineers, therefore, might need to ask how long does it take Polyurethane to dry?
Let’s see what the quick answer to this question is:
How Long Does Polyurethane Take to Dry?
Polyurethane takes an average of 2-24 hours to dry. The drying time is related to the type of polyurethane used. Water-based Polyurethane typically takes 2-3 hours to dry, while the oil type takes about 8-12 hours. In addition, temperature, humidity, and paint thickness are also important factors affecting curing.
But there’s more to know about it.
In this article, we will discuss:
- Oil-based and Water-based polyurethane sealer dry time.
- Drying time & curing.
- Polyurethane sheen.
- How important is the Polyurethane drying and cure time?
- Factors affecting the Polyurethane drying and cure time
- How to speed up the drying of Polyurethane
These topics are not all that we will be discussing but will form the main crux of this article.
Stay connected and read till the end.
Drying Time Vs cure time
Drying refers to the evaporation or reduction in the moisture content of a substance or material. The result of drying must be solidification.
This is very similar to the liquid form and pastes waxes.
Curing is more of a chemical process. The complete chemical reaction occurs in the finish to transition from liquid form to liquid form. A typical example of a finish that operates this way is the polyurethane varnish.
All two parts catalyzed and water finishes cure like the polyurethane varnish.
The most common types of driers are shellac and lacquer. These substances work by completely absorbing moisture from the material.
How important is the Polyurethane Drying Time?
The Polyurethane drying time is very crucial to the quality of the product the Polyurethane is applied on.
Polyurethane is organic and therefore contains some level of water.
Therefore, the compound must go through a phase of moisture loss to achieve a great sheen.
Please remind: For 48 hours after the final coat, avoid placing heavy objects and furniture as it will not yet have sufficient strength.
Factors Affecting Polyurethane Drying & Cure Time
The drying and curing time of Polyurethane depend on a variety of factors.
Some factors are spontaneous, while others are influenced by the choice of surfaces or the nature of the material.
Types of polyurethane
Water-based polyurethanes can dry in 2-3 hours and fully cure in 24-72 hours. oil-based polyurethanes dry in 8 hours to 12 hours and take 15-30 days to cure fully.
Oil-based Polyurethane Cure Time
The welcome answer is that it takes 8-12 hours for the oil-based polyurethanes sealer to dry.
Let’s analyze this section of the article by using an example of a just painted wooden floor:
- Give it at least 24 hours before you move on to the floors. Ensure that the floors are dry before walking on them. Checking for stickiness is an important method.
- Sanding is also necessary when the dryness is confirmed.
- You can now apply a second coat.
- You can walk on the floors in your shoes after 48 hours.
- You can move back the furniture after four days.
- Keep pets away for now to avoid disruption of the curing process.
- It takes an average of a month to cure completely.
- Keep the floor uncovered for a long time (a month) for best results.
Water-based polyurethane Cure Time
Water-based Polyurethane can be dried in 2-3 hours and fully cured within 24-72 hours.
Here is how you can dry your wood floor with water-based Polyurethane.
- Ensure that you wait for 6 hours before walking on the floors.
- After elapsed above, ensure that the floor doesn’t look wet and feels tacky.
- During this time, don’t walk on the floors with your bare feet.
- Keep pets as far away as possible.
- You can now do the light sanding.
- Give it a day before walking on your shoes.
- It also takes about a month to cure, and it works best when the floor is uncovered.
Temperature
The environment’s temperature plays a crucial role in drying and curing because the increasing air temperature will increase drying. At the same time, a decrease will lead to a delay in drying time.
Humidity
This works together with air temperature. Polyurethane takes longer to dry when the humidity is too high. The ideal humidity level for drying water-based polyurethane is 40-50% and 60-70% for oil-based polyurethanes. High humidity certainly prolongs drying time.
Ventilation
A well-ventilated room can influence drying and curing time. Fans are a great way to promote ventilation and get rid of polyurethane odors.
Kind of Wood
Different woods(Hardwood, softwood, plywood, or MDF) have different surface roughness, and smooth wood surfaces dry easily. In addition, some woods produce natural oils that can inhibit the drying or curing of polyurethane.
Sheen
Polyurethane is an organic compound that works by polishing the surface of your wood or suitable material. Various types of finishes add to the sheen of your wood surface.
The drying time of different paints has a lot to do with the brand. Generally speaking, the satin type is the fastest drying polyurethane available for products of the same brand, semi gloss polyurethane second, and glossy the slowest.
- Matte: This has a low luster; hence it is not marketable.
- Satin: This is more marketable because it has just the proper luster.
- Semi-gloss: This is also close to neutral but has more luster than Satin.
- High Gloss: This has a very high quality in luster. It is not used often and is only used on exotic and sophisticated hardwood floors.
The type of surface largely influences the choice of finish, and a poor choice could affect the subsequent finishing processes and quality of the work.
Starting Surfaces
Log(bare wood) or sanded wood has an open grain that easily absorbs the first coat of polyurethane in a shorter drying time. Subsequent polyurethane coatings take longer to dry. If you apply multiple layers, the resin in each layer will be cross-linked, so make sure the previous layer is completely dry before proceeding to the next step. Below is an approximate polyurethane cure time table.
| Water-based Poly | Oil-based Poly | |
| Time between each layer | 6-8 hours | 1 day |
| Touch dry | 24 hours | 2-3 days |
| Can place items | 2-3 days | 4-7 days |
| Completely Cured | 14 days | 24-30 days |
Thickness & Layers
Many measurements are used for the thickness of layers. However, the standard thickness is ½ inches. Some woodmen use 11/32, though. In addition, the number of layers of polyurethane is also an important factor. Applying three layers of polyurethane will definitely dry more slowly than applying two layers.
Environmental conditions such as temperature, and humidity are crucial to the drying and curing rate of Polyurethane because they directly influence the curing process. More humidity will increase the moisture of the Polyurethane and vice versa.
How Long Does Polyurethane Take to Dry on Different Surfaces?
On average, it takes 24 hours for Polyurethane to dry generally on different surfaces.
The drying differs when applying polyurethane on metal, furniture, wood, stair, or countertop. When Polyurethane is used on floors, give it at least 24 hours to dry. After it has completely dried and cured, you can safely walk on the polyurethane wood floors.
When applying polyurethane to hardwood floors, you are actually applying a layer of polyurethane resin dissolved in a liquid solvent to the hardwood floor. You should apply at least three coats of polyurethane, or even more, to provide a smooth finish and adequate protection.
| wood furniture | 2-12 hours |
| cabinets | 2-24 hours |
| wood table | 2-12 hours |
| stairs | 2-48 hours |
| paint | 24-48 hours |
on wood furniture
The dry time of Polyurethane on furniture is 2-12 hours when the right atmospheric conditions and temperature are met.
It cannot be overemphasized that painting on wet wood furniture will damage your wood project or result in a bad polyurethane finish. All you have to do is to ensure the right weather conditions and proper ventilation.
on cabinets
It takes about 2 to 24 hours to dry on cabinets. The drying time for cabinets is almost the same as the wood furniture drying time.
However, the type of poly you wish to apply determines the drying time. While water-based poly may take not less than 2 hours, oil-based takes longer, up to 24 hours, on average.
on stairs
It takes between 2 to 48 hours for poly to dry on stairs. Again, you also have to factor in the type of Polyurethane you’re using.
Typically, water-based Polyurethane can take up to 48 hours to dry on stairs. Oil-based Polyurethane takes up to 24 hours. Don’t forget that stairs made of wood will dry at the same rate as their furniture counterparts under the same weather and ventilation conditions.
on wood table
It takes at least 2 hours for Polyurethane to dry on furniture like wooden tables.
It would help if you also remembered that ventilation and weather conditions play an essential role in determining the duration the poly will dry. Besides, the type of polyurethane coatings applied on the wood table can also influence the drying time.
on paint
It takes about 24- 48 hours for Polyurethane to dry on paint, irrespective of which kind.
It takes much less the water-based Polyurethane (12-24 hours). But if the oil-based Polyurethane is your choice, it won’t take less than 24 and 48 hours. Other coats, such as stain, paint, or primer, also take a long time to dry.
5 Ways to Speed up the Drying of Polyurethane
Quickening the drying of Polyurethane can have adverse effects on the delivery of the products if not done correctly.
Therefore, the right means must be employed to speed up the drying process of Polyurethane.
Here are five great ways to speed up the drying of Polyurethane:
1. Increase the heat of the environment
As earlier stated, the environment’s temperature influences the rate at which your poly dries. For poly to dry fast, it requires much heat. This is why you should heat the entire workspace to speed up the drying rate.
Specifically, you should consider increasing the temperature, preferably to somewhere around 72 Fahrenheit (22.2 degrees Celsius). This way, you can be sure the poly will dry faster than you initially thought.
2. Reduce humidity
Humidity slows down the rate at which your poly dries. Hence, as much as possible, you should boost the drying process by ventilating the room by putting a fan.
Alternatively, you should open the windows to allow enough air to come in. Using air conditions is not recommended. Air conditioning is the only humidity-lowering method you shouldn’t use.
3. Applying Coats in Thin Layers
To ensure that your poly dries more quickly, you should apply them in thin coats. This technique was derived from conventional painting. Applying Polyurethane in thin layers will boost drying.
Besides, keeping the application thin also ensures the even distribution of the polyurethane coatings on the surface. This way, the poly will use neither drip nor pool.
4. Remove all sanding dust and dirt from the surface
Preparing the surface of the wood will significantly help in drying the Polyurethane. Ensure the sand, prime, and clean the surface before applying the poly coat. The drying time will prolong if the surface is wet or dusty.
After a light sanding, make sure to remove all sanding dust grime and deposit them on the surface. The more smooth and clean the surface, the more even the poly coat will spread across the surface. The result is a quicker drying time.
5. Using the correct type of Polyurethane
The drying time for each type of your poly varies. Generally, there are two types of Polyurethane: oil-based and water-based poly.
It’ll take about 4 hours to 24 hours for oil-based poly to dry. This depends on the formula. However, it’ll take up to 30 days before it fully cures.
Water-based takes 2 hours to dry before you apply the next coat. This happens only in optimal conditions. Within three days, water-based poly is fully cured.
Reminder: When using any type of paint, sealant, or stain, ensure that proper protective equipment (respirator or mask, disposable gloves) is used to avoid exposure to volatile organic compounds (toxic) and to prevent contact of polyurethane with skin, mouth, and eyes.
FAQs
How long does Polyurethane take to dry before sanding?
It takes between 24 to 48 hours for Polyurethane to dry before sanding. When applying Polyurethane, you must allow it to dry completely. Applying sandpaper to a dry surface will result in a shoddy result.
However, you’ve got to choose your poly. After drying, you can proceed to the sanding process.
How long to wait between coats of Polyurethane?
The time to wait between multiple coats of poly largely depends on whether you use oil-based or water-based Polyurethane. You may have to wait for 2 to 4 hours for the water-based poly, and the oil-based Polyurethane takes about 24 hours. Regardless, the waiting time to recoat your primer or paint, on average, is 5 hours.
A simple way to judge is: When you can touch the finish without it sticking to your hands, you can apply a second coat of polyurethane finish.
How long does Minwax Polyurethane take to dry?
Minwax Polyurethane takes, on average, 4 to 6 hours to dry. Some allow it to dry for 12 hours before any material usage. It could take much longer, depending on the surface.
After drying, lightly sand the entire surface with fine sandpaper (use 220- or 320-grit) to ensure an even polyurethane finish and proper adhesion. Remove all dust.
Final Words
If you find yourself in a situation where you are asked how long it takes for Polyurethane to dry, this article has provided enough information for a quick answer.
Most water-based Polyurethane dry within 2-3 hours, while oil-based Polyurethane dries within 8-12 hours. However, complete curing may take 3-5 days, depending on the temperature and humidity of the environment.
Polyurethane is a solvent and therefore contains a good amount of water. This could affect the quality of the surface it is applied on.
Therefore, the moisture content must be reduced to the minimum. The effective means of drying and curing are increasing temperature and reducing humidity. The nature of the surface also affects the rate of drying and curing.
My name is Mark, and I am a software engineer and the founder of OnWoodWorkingArt.
I grew up with a passion for woodworking and now have my woodworking studio with a group of like-minded friends who love to create woodworking. My dream is to have a more extensive workshop and be able to make woodworking my main business.
