How Long Does Polyurethane Take to Dry? The Most Complete Guide
Polyurethane is the perfect finish for wood, and many wooden projects are not complete without a polyurethane coating. Before you start to apply it though, it’s important to understand the polyurethane dry time. There are various different types of polyurethane available – each one with unique properties and curing times. If you are asking the question “how long does polyurethane take to dry?”, then follow our complete guide below for everything you need to know about the drying time for polyurethane, and the different products available.
- 1 How Long Does Polyurethane Take to Dry?
- 2 The Different Types of Polyurethane
- 3 Polyurethane Cure Time Table
- 4 Polyurethane Drying and Curing
- 5 Factors That Influence Curing Times
- 6 Tips and Tricks for a Faster Drying Time
- 7 How Long for Polyurethane to Dry in Layers
- 8 Frequently Asked Questions
- 8.1 How Long Does Polyurethane Take to Dry?
- 8.2 How Long Does it Take for Water-Based Polyurethane to Dry on Hardwood Floors?
- 8.3 What is the Oil-Based Polyurethane Dry Time?
- 8.4 What is the Water-Based Polyurethane Cure Time?
- 8.5 How to Speed Up Polyurethane Drying Time?
- 8.6 How Long Does it Take for Minwax Polyurethane to Dry?
How Long Does Polyurethane Take to Dry?
For water-based polyurethane, the drying time is about 48 hours. For oil-based polyurethane, it takes around 48 hours to dry. After this time, you can walk on the surface or touch it. The complete drying takes much longer.
This depends on the type of polyurethane you use, how you apply it, and what the external conditions are like. We have outlined all of these factors in detail below.
The Different Types of Polyurethane
Before looking into drying times, you will need to understand exactly which product you are working with. There are various different types of polyurethane coatings available, each one with a unique drying time. To better understand this, we have outlined some of the main considerations below for polyurethane coatings.
Water-Based or Oil-Based Polyurethane
First, you will need to understand exactly what polyurethane is and how it is formulated. Polyurethane coatings, or varnish, is made up of polyurethane resins that are dissolved and carried by a liquid solvent. This basically forms a type of plastic in liquid form. When looking at the liquid base of polyurethane, there are two options: water or oil. Both of these produce very different products with unique polyurethane dry times.
Water-based polyurethane is a safer and less toxic option. These products contain far fewer amounts of VOCs – that is if they contain any at all. Water-based products do not produce strong odors, and they are safer and easier to work with. Because water evaporates quickly, this type of polyurethane is much faster drying. The polyurethane cure time for water-based products is also lower because these finishes produce much thinner coatings. You will likely have to apply more coatings though – especially because water-based products are typically less durable.
Oil-based polyurethane is a different story. Unlike water-based products, these finishes are applied slightly thicker. This thickness, combined with the oil composition, makes the polyurethane dry time significantly longer. However, you will achieve a stronger, more durable finish. Oil-based polyurethane can contain high levels of VOCs, and these products can be fairly harmful due to the many chemicals. Oil-based products also release a stronger odor.
An important difference between these two types of polyurethane is their clarity. Both types of finish go on clear, but oil-based products will often yellow or darken over time. Water-based polyurethane generally maintains a better level of clarity over the years.
The Type of Sheen
Another factor to consider on the drying time for polyurethane is the type of sheen that the product has. Polyurethane varnishes come in three different types of sheen. These are the level of glossiness, or lack of gloss, that the finish offers after it has dried. We have outlined the different sheen types below:
- Satin: A satin finish is not as shiny as others. This type of polyurethane has an almost matte look, with a very minimal, subtle shine to it. How long does polyurethane take to dry with a satin coating? This type is the fastest drying polyurethane available.
- Semi-gloss: Semi-gloss polyurethane offers a finish that has some shine, but is not as shiny as high-gloss options. This is the middle ground between glossy and flat. Semi-gloss polyurethane is a popular choice thanks to its versatile nature and durability. This type of polyurethane dries faster than high-gloss but slightly slower than satin products.
- High-gloss: High-gloss polyurethane offers a completely shiny and slick-looking finish. This type of varnish is really durable and provides great flexibility. High-gloss polyurethane can be used indoors and outdoors for various wooden surfaces. This type of finish takes slightly longer to dry.
Polyurethane Cure Time Table
Now that we have covered the basic types and formulations of polyurethane, we can compare the different styles side by side. How long does polyurethane take to dry? Take a look at our polyurethane cure time table below to gain a better understanding of the drying times for each type. This is just a general overview. It depends on the temperature and humidity, as well as the surface.
|Ready for another Layer||8 hours||24 hours|
|Dried to touch||24 hours||48 hours|
|Placing things on the surface*||> 2 days||> 4 days|
|Fully cured||20 days||30 days|
*Wait for a month before you place materials with plasticizers (e.g. rubber mats) on the surface. Otherwise, you will have visible marks on the floor.
Polyurethane Drying and Curing
When talking about polyurethane dry time, or polyurethane cure time, there is a distinct difference between the two. Dried polyurethane is not cured polyurethane. When asking how long does polyurethane takes to dry, it is important to understand these two definitions.
Drying is when the external finish of the polyurethane hardens. This just means that the polyurethane is no longer in a liquid form, and it isn’t tacky or wet. This does not mean that the coated surface is ready for use though. Dried polyurethane can still easily get damaged or wrinkled by too much pressure. If you have a floor or countertop coated in polyurethane, make sure that you do not put it under heavy use when it is just dry.
Curing is a more thorough process where the polyurethane completely hardens throughout. This is when the polyurethane has been completely exposed to oxygen and has gone through a complete chemical reaction with the oxygen. Cured polyurethane is the finish in its final, hardest form. Once cured, you can apply regular pressure to the surface. Curing is a much longer process and can take anywhere between 24 hours to a month.
Factors That Influence Curing Times
Polyurethane can also dry at different times depending on external factors. If you use the exact same product in two different conditions, the drying time will change. We have outlined some of the most important factors that will influence drying time below.
One of the most important factors when applying a wood finish is the external temperature. The best conditions would be anywhere around 70 degrees Fahrenheit. If the temperature is too cold below this, then the polyurethane will take far too long to dry. Drying in cold conditions can cause a strange white film to develop over the polyurethane. If the temperature is too hot, then this might affect the resulting finish of the polyurethane.
Ideally, you want a humidity of 50 – 70% when applying polyurethane finishes to the wood. If the humidity is too high, the finish will struggle to dry properly, and the resulting finish could be affected in the way it looks and adheres to the wood. If humidity is an issue, then it’s best to use oil-based polyurethane. This is because water-based products are more sensitive to humidity.
Thickness of Layers
The other factor that determines the polyurethane drying time is the thickness of the layers applied. Quite simply, the thicker the coats, the longer the polyurethane will take to dry. This is influenced by two different factors. These are the method of application and the product used.
If you paint polyurethane on with a brush, the layers will generally be a bit thicker. This will take longer to dry. If rolled or sprayed on, the layers of polyurethane will be thinner. This will result in a significantly faster drying time. You can also get certain special wipe-on polyurethane products for, particularly thin and fast-drying layers.
Then there is the type of polyurethane used that will influence this. Water-based products tend to be a lot thinner than oil-based products. If you are using a water-based solution, the thinner layers will result in a speedier drying time. Thicker oil-based polyurethanes will be much slower.
Tips and Tricks for a Faster Drying Time
Now that we know what makes polyurethane dry and what influences its curing time, we can try to add our own influences if we want to make the product dry faster. If you are struggling to get the polyurethane to dry quickly, then follow our top tips below to help get the process going faster.
- Apply heat in cold conditions. If the weather is too cold for the polyurethane to dry properly, you can simply apply a heat source to speed up the process. This can include things like a wall heater or hairdryer. Just make sure that you apply a gentle layer of heat – too much and the finish will be affected.
- If the polyurethane comes on too thick, you can smooth it out for a faster drying time. Using a paint roller works very well. Simply roll over the applied finish to create even, thin layers. This also allows the coating to be completely smooth.
- Check the weather. This may sound silly, but it is so important. Always check the weather report if you are applying polyurethane outdoors. If there is rain or humidity heading through, then reschedule your DIY project.
- Water-based polyurethane is particularly sensitive to humidity. If you are applying the finish in humid conditions, then rather choose an oil-based product. This will dry faster in very humid weather, and it will leave you with a longer-lasting result.
- Make sure that the surface you are applying the polyurethane to is properly prepared. A clean, sanded, and smooth wooden surface will help the polyurethane to adhere better and dry faster.
How Long for Polyurethane to Dry in Layers
How long does polyurethane take to dry when painting in layers? This is important to understand because when you apply this finish, you will need to do it in multiple coats. You will need to know when to apply the next layer and when the underlying coat is dry enough.
To know when the polyurethane layers can be applied, you will need to understand the difference between dry times and cure times. Apply the first layer and leave it to dry. Depending on the product, this could take anywhere from 1 hour to 8 hours. When we say dry in this case, we don’t mean fully cured though – just dry to touch.
The polyurethane should not be tacky or wet anymore. When you can touch the finish, you can apply a second coat. The same rule applies to a third coat. After the last coat, you will need to leave the polyurethane to cure fully before use.
You can use a paint sprayer to apply this finish in the thinnest layers possible. This will allow you to apply the finish much faster and in much thinner layers. Just make sure that the sprayer can handle polyurethane. Otherwise, rolling or painting on the finish is recommended.
Frequently Asked Questions
How Long Does Polyurethane Take to Dry?
Water-based products dry in around 6 hours, and oil-based products usually take around 24 hours. Be sure to consult the manufacturer’s guidelines on the specifics of this.
How Long Does it Take for Water-Based Polyurethane to Dry on Hardwood Floors?
One of the most popular applications for polyurethane is over wooden flooring. Many will then ask “How long does it take for water-based polyurethane to dry on hardwood floors?”. As mentioned earlier, the product and environmental conditions play an important role here. Typically, water-based finishes dry in about 6 hours and are cured in about 48 hours. You should wait around 24 hours before walking on the floors.
What is the Oil-Based Polyurethane Dry Time?
Typically, an oil-based polyurethane dry time is around 24 hours. This could be 48 hours for certain products. Always consider the specific product and application conditions for a more accurate drying time.
What is the Water-Based Polyurethane Cure Time?
A water-based polyurethane cure time can be around 24 hours to 72 hours for a full cure. Drying times for water-based products are usually around 6 hours. Of course, this varies depending on the product and environmental conditions.
How to Speed Up Polyurethane Drying Time?
The drying time for polyurethane can be sped up by altering the temperature or thickness of layers. Ideally, you want a temperature around 70 degrees Fahrenheit without too much humidity. Thin layers dry faster.
How Long Does it Take for Minwax Polyurethane to Dry?
Minwax is one of the most popular polyurethane brands, so naturally many people ask “How long does it take for Minwax polyurethane to dry?” This depends on the product specifications and external conditions. Their fast-drying products can dry in 4 – 6 hours for recoating but should be left for 24 hours before use.
Drying time for polyurethane is something that you should know before starting a new woodworking job. This popular finish comes in many varieties, each one offering a different drying time. When wondering how long for polyurethane to dry, follow our guide above and you should have a better understanding of the different products dry times and what you can do to make sure the finish dries as efficiently as possible. Happy DIYing!