You might be wondering how long polyurethane wood floors take to dry. Polyurethane is a type of finish that is applied on the surface of the floor to protect and give it a shine. Once you have finished applying polyurethane, your floor will need time to dry before anyone can walk on it again. In this blog post, we will discuss 6 things you should know about polyurethane wood floors drying time!
What Determines Polyurethane Wood Floors Drying Time?
Polyurethane on wood floors needs to dry and cure before you resume normal activities. This will take time, depending on the type of poly varnish being used, how absorbent your wood is, temperature and humidity.
- The polyurethane varnish: there are a variety of polyurethane types, each with different properties. For example, oil-based will dry faster than water-based and heavier grades may take longer to cure or dry.
- Wood type: maple is more absorbent than oak for instance. The denser the wood, the longer it will take to dry.
- Temperature and humidity: polyurethane on wood floors needs a temperature of at least 50 degrees Fahrenheit for proper drying; more time is required during colder temperatures or humid conditions.
- Weather conditions: rain or snow may cause your flooring project to stay wet longer than normal. Extreme heatwaves can also affect how long poly takes to dry unless precautions are taken such as air conditioning.
- Surface: The “open grain” of wood will make it easy to absorb the first coat, but subsequent coats may take longer.
- Impurities: Dust or other debris can delay the polyurethane wood floors drying time by causing imperfections on the surface. Clean and let dry the surface before applying the poly.
All these factors will affect how long polyurethane takes to dry.
Polyurethane Drying and Curing Time
It may seem like the words “drying” and “curing” are interchangeable but there is a difference. Understanding this helps in understanding finishes because they each refer to different ways of forming that film.
Drying time
For a polyurethane finish to be considered dry, the surface shouldn’t feel sticky or appear wet. At this point, you can walk on it barefoot without your feet feeling tacky. To avoid causing any scratches or other blemishes to the flooring though, make sure that everybody walks in socks and avoids placing anything heavy like furniture pieces until you’re 100% confident that the finish has dried.
The time it takes for water-based polyurethane to dry varies. They can require up to 8 hours but are often done in 4. Oil-modified polyurethane on the other hand takes 12 – 24 hours!
Drying time is what allows you to access your polyurethane wood floors in between coats. In some cases, you can even apply 2 coats of finish in a single day.
Your floors will be off-limits for 24 hours after the final coat and it is the best way to avoid any damage. If you can, hold off moving your furniture back into that room for 3-7 days after finishing the flooring project.
Curing time
After the drying process comes curing, where it undergoes three key processes:
- The first is the crosslinking of polyurethane molecules with oxygen. This creates a tough bond between the finish and your wood flooring as it hardens.
- Second, all the solvents will evaporate.
- The third and arguably the most important, the strong odors cease. The odor is an indicator that the curing process is still taking place.
This process takes a few weeks on average but can be shortened if humidity levels are low or temperatures are very high during the day (depending on your environment).
Typically, water-based polyurethanes need between 7 and 14 days to cure while oil-modified ones take 30.
Once cured, you can allow foot traffic to resume on it once more.
Frequently Asked Questions
How long does it take for the first coat of polyurethane to dry?
The first coat of polyurethane usually takes between 4-12 hours to dry, depending on the factors mentioned above.
How can I speed up the drying process?
Low humidity and high temperature will speed up the polyurethane wood floors drying time. For example, try opening your windows for a day to allow some fresh air in! Using a dehumidifier in the room can also help speed up drying time.
You can also use a fan over freshly polyurethaned wood to blow away some excess water vapor from wetter areas before it cures. This will allow for faster curing time as well.
How do you know when polyurethane is dry?
Check the polyurethane surface for tackiness. The dryer it is, the less sticky it will feel to your finger.
Always test tackiness between coats.
Can you stay in the house while floors are refinished?
Yes, you can stay in the house while polyurethane wood floors are drying. Just make sure to avoid any areas of wet poly for at least 24 hours after application! Once cured, you can allow foot traffic on it once more.
In the case of oil-based polyurethane finish, they will emit strong odors so it is advised to stay out of the house for a day or two.
How long until you can walk on polyurethane floors?
To walk on polyurethane floors, you can wait 24 hours for the first coat to dry or a maximum of 48 hours after you’ve applied your second coat.
In general, polyurethane floors should not be walked on until they have been left alone for at least 12-24 hours.
Generally, it’s best to keep people off of freshly coated finishes (once dried) while still leaving them exposed to good ventilation as much as possible because this reduces off-gassing odors that may linger.
Why is my polyurethane still sticky?
If your polyurethane floor is still sticky, it is probably because you’ve applied too many coats. See this article on how many coats of polyurethane for hardwood floors.
You should wait at least 12 hours, or more preferably 24-48 hours for each coat to dry before applying another one.
If the poly is still tacky after 48 hours of drying time you may need an additional sanding and recoating session. In that case, it’s best to apply two light coats instead of three heavy ones so as not to overload the finish with product that could cause problems down the line such as being overly difficult to refinish if necessary (i.e., peeling).
