How to Fix Uneven Polyurethane

There is nothing quite like the look of a well-done polyurethane finish. It can make wood look rich and luxurious. However, if your polyurethane finish is uneven, it can really detract from the overall look of your project. Thankfully, there are a few things you can do to fix the issue and get your finish looking great again. In this post, we’ll walk you through some easy ways how to fix uneven polyurethane. Let’s get started!

How to Fix Uneven Polyurethane

Summary: If you have uneven polyurethane, there are a few things that you can do to fix the problem. You can sand the area with a fine grit sandpaper to level out the surface, or you can use a filler such as silicone or epoxy to fill in any gaps.

Why Should You Fix Uneven Polyurethane?

Most people don’t think twice about fixing uneven polyurethane. After all, it’s not exactly a high-priority item on most to-do lists. However, several good reasons exist to fix uneven polyurethane as soon as possible. First, uneven polyurethane can create trip hazards. Second, it can make doorways and stairways difficult to use.

Third, it can damage flooring and furniture. And fourth, it can give your home an unsightly appearance. So if you have uneven polyurethane, don’t wait to fix it. By taking care of the problem now, you can avoid multiple potential headaches down the road.

7 Ways to Follow on How to Fix Uneven Polyurethane

Polyurethane is a type of protective finish that is often used on wood floors. It is durable and easy to clean, making it a popular choice for homes with children and pets. However, one problem that can occur when applying polyurethane is that it can look uneven. If you have ever dealt with this problem, you know how frustrating it can be. Luckily, there are a few ways to fix uneven polyurethane and make your floors look new.

1. Sand Down the Floor

One way to fix uneven polyurethane is to sand down the floor and start over. This method works best if the unevenness is not too severe and if the floor is made of hardwood. If you decide to go this route, make sure to use fine-grit sandpaper so that you don’t damage the floor. Once you have sanded down the floor, vacuum up the dust and apply a new layer of polyurethane. 

2. Use a Tinted Polyurethane

If the problem with your polyurethane is that it is not the right color, then you may want to try using a tinted polyurethane. This type of polyurethane comes in various colors, so you should be able to find one that closely matches the color of your floor. Applying a tinted polyurethane is a great way to fix an uneven coat of polyurethane without having to sand down the entire floor.

3. Use a Polyurethane Stripper

If the problem with your polyurethane is that it is too thick, you can use a polyurethane stripper to remove it. First, sand the area with 220-grit sandpaper to rough it up. This will help the stripper adhere to the surface. Next, apply the stripper with a paintbrush and let it sit for 15 minutes. Then, use a putty knife to scrape off the stripper and the polyurethane. Finally, sand the area smoothly with 220-grit sandpaper.

You Can Check It Out to Fix Weathered Wood

Apply the Stripper With a Paintbrush

4. Apply Heat

If the problem with your polyurethane is that it is starting to bubble, you can try using a hairdryer to apply heat. Set the hairdryer on its lowest setting and hold it about six inches away from the bubbling area. Move the hairdryer back and forth until the bubbling stops.

5. Use a Weighted Roller

If you are having trouble getting an even coat of polyurethane with a brush, you can try using a weighted roller. This will help to distribute the polyurethane more evenly and prevent brush strokes from being visible.

6. Use Sandpaper

If the problem with your polyurethane is that it is not smooth, then you may be able to fix it by using sandpaper. Start with coarse-grit sandpaper and sand the entire floor. Then, vacuum up the dust and apply a new layer of polyurethane. Be sure to use fine-grit sandpaper this time so that you don’t damage the floor.

7. Hire a Professional

If you have tried all the above methods and still can’t get your polyurethane to look even, you may need to hire a professional. A professional flooring contractor will be able to sand down your floors and apply a new layer of polyurethane. This may be the best option if you have a large area of uneven polyurethane or if your floors are made of delicate materials.

That’s it! You’ve now learned how to fix uneven polyurethane. Remember, if you are having trouble fixing the problem yourself, you can always hire a professional flooring contractor to do it for you.

You Can Check It Out to Fix Bubbles in Engineered Hardwood Floor

What Causes Uneven Polyurethane

You’ve just applied a fresh coat of polyurethane to your floors, and it looks wonderful – smooth and even with a nice, glossy finish. But then you notice that some areas seem to be drying faster than others, resulting in an uneven appearance. So, what causes this problem, and how can you fix it?

Applied a Fresh Coat of Polyurethane

There are several possible causes of uneven polyurethane. If the temperature in the room is too warm, the poly will dry too quickly and will not have time to level out. Alternatively, if the humidity is too high, the poly will absorb moisture from the air and will again dry too quickly. Another possibility is that you didn’t stir the polyurethane properly before applying it, resulting in streaks or an uneven finish.

Fortunately, there are some simple solutions to these problems. If the room is too warm, turn on a fan or open a window to cool things down. If the humidity is too high, use a dehumidifier to remove excess moisture from the air. Finally, be sure to stir the polyurethane thoroughly before applying it – and don’t forget to stir occasionally during application as well to prevent streaking.

With these tips in mind, you should be able to achieve a smooth, even finish on your next project. Keep reading for more information about how to fix uneven polyurethane.

10 Mistakes People Make When Fixing Uneven Polyurethane

Trying to fix an uneven polyurethane job can be frustrating. Uneven polyurethane is often the result of user error, and it can be tricky to figure out how to fix it without making things worse. Here are ten mistakes people make when attempting to fix uneven polyurethane and how to avoid them:

  1. Not sanding before applying a new coat. Over time, polyurethane can become dull and sticky. So if you’re applying a new coat of polyurethane over an old one, it’s important to sand the surface first to create a smooth, even surface. Otherwise, you’ll just end up with another layer of uneven polyurethane.
  2. Applying too much pressure when sanding. When sanding uneven polyurethane, it’s important to use light pressure. Otherwise, you risk creating more unevenness.Applying Too Much Pressure When Sanding
  3. Sanding in only one direction. Sanding in only one direction will create streaks in the polyurethane. To avoid this, sand back and forth in a criss-cross pattern.
  4. Not using enough paint thinner. Paint thinner plays an important role in thinning the polyurethane so it can be evenly applied. If you don’t use enough paint thinner, the polyurethane will be too thick and will not spread evenly.
  5. Apply the polyurethane too thickly. Polyurethane should be applied in thin coats for the best results. If you apply it too thickly, it will take forever to dry and will likely be full of bubbles. Not to mention, it will be very difficult to remove any excess polyurethane once it’s dried!
  6. Not giving the first coat enough time to dry before applying the second coat. Each coat of polyurethane needs time to dry before the next coat can be applied properly; otherwise, the coats will start to meld together and will be difficult to sand smooth later on. For best results, wait at least 24 hours between each coat of polyurethane.
  7. Applying a second coat before the first coat is fully cured. Even though each individual coat needs time to dry, the entire project will go faster if you can apply subsequent coats before the previous one is fully cured. This way, you won’t have to wait as long for the overall project to complete. Just be sure not to apply the second coat too early, or you’ll risk creating more unevenness.
  8. Not removing all of the dust before applying a new coat. No matter how hard you try, some dust particles will always be left behind after sanding. These dust particles can create streaks and imperfections in the next coat of polyurethane, so it’s important to remove them before continuing. The best way to do this is with a vacuum equipped with a small attachment, such as a soft brush or dusting wand.
  9. Applying heat to speed up the drying process. It’s tempting to want to hasten the drying process by applying heat, but this is a big mistake! Applying heat will cause bubbles in the wet polyurethane, which will then be difficult ( if not impossible ) to remove later on.
  10. Not allowing enough time for the final coat to cure fully. The final coat of polyurethane needs time to cure before it can withstand heavy use properly. Depending on environmental factors, such as humidity and temperature, this could take anywhere from 24 hours to a week or more.

Be patient and allow adequate time for curing; otherwise, you’ll have to redo the entire project!

Polyurethane Needs Time to Cure

What Is the Best Way to Apply Polyurethane?

Polyurethane is a great way to protect wood and add shine to its appearance. It is important to follow a few steps to achieve a smooth and even finish. Firstly, prepare the surface by removing any dust or debris and sanding lightly to remove any roughness. Before applying the polyurethane, always test it on a small, inconspicuous area to ensure proper adhesion and drying.

To avoid drips and unevenness, use a high-quality brush or foam applicator to apply the polyurethane in thin coats. Sand lightly between coats to promote adhesion and create a smooth finish. Depending on the desired level of protection, repeat the process until you achieve the desired level of shine and protection. Always work in a well-ventilated area and wear protective gear while working with any chemicals.

What Is the Best Type of Polyurethane to Use?

There are different types of polyurethane that can be used for a variety of purposes. The best type of polyurethane depends on the specific application and the desired end result. For example, water-based polyurethane is great for protecting surfaces from scratches and stains, while oil-based polyurethane is best for protecting wood floors from heavy foot traffic.

Some types of polyurethane are also better for outdoor use, as they are more resistant to UV rays and weathering. Additionally, high-performance polyurethanes are available that offer superior abrasion resistance, scratch resistance, and chemical resistance compared to standard options.

When choosing a polyurethane, consider factors such as durability, application method, drying time, and whether it is compatible with the surface being coated. Ultimately, selecting the best polyurethane involves evaluating the performance properties and finding the right fit for your specific needs.

What Are Some Common Mistakes to Avoid When Applying Polyurethane?

Polyurethane is a popular finish used to protect and enhance the beauty of wood furniture, floors, and trim. However, applying this finish can be tricky, and mistakes can ruin the final result.

Here are some common mistakes to avoid when applying Polyurethane:

  1. Not properly preparing the surface: Before applying Polyurethane, it’s crucial to ensure the surface is clean and free from any dirt, dust, or debris. Sanding the surface using fine-grit sandpaper can also help improve adhesion.
  2. Applying too much Polyurethane: Applying too much Polyurethane can result in brush marks, bubbles, and drips on the surface. It’s essential to apply a thin and even coat and allow it to dry completely before applying another.
  3. Applying Polyurethane in a humid or dusty environment: Humidity and dust can affect the drying time and final finish of Polyurethane. Applying Polyurethane in a clean, dry, and well-ventilated area is best.
  4. Not stirring the Polyurethane thoroughly: Polyurethane can separate in the can, which can result in an uneven finish if not stirred properly. Stirring the Polyurethane thoroughly and frequently throughout the application process is crucial.
  5. Sanding too aggressively: Sanding can help remove imperfections and smooth the surface before applying Polyurethane. However, sanding too aggressively or using coarse grit sandpaper can result in scratches and ruin the final finish.
  6. Not allowing enough drying time: Failure to allow sufficient drying time between coats can result in a tacky or uneven finish. It’s essential to follow the manufacturer’s instructions and allow each coat to dry completely before sanding or applying another coat.

Can Uneven Polyurethane Finish Be Corrected After It Has Dried?

An uneven polyurethane finish on a wood surface is certainly an annoyance, especially if it has already dried. However, if you are facing this issue, there are still a few ways to correct it. The first and easiest way to correct uneven polyurethane finish is by sanding. You can sand off the excess polyurethane on the higher areas of the finish using fine-grit sandpaper.

Remember not to sand too much, or you may end up sanding the wood underneath. Once you have removed the excess, you can apply a new coat over the entire surface to achieve an even finish. Another way is to use a specialized thinning agent to even out the finish. This process involves rubbing a small amount of the thinning agent on the surface of the finish, which can help to level out the uneven finish.

However, this method may not be as effective as sanding, and you should be careful not to put too much thinning agent as it can damage the finish. Ultimately, it is always better to ensure your polyurethane finish is even before it dries by carefully applying a consistent amount of polyurethane coating.


Uneven polyurethane can be frustrating, but luckily there are a few ways that you can fix it. The best method for fixing uneven polyurethane will depend on the problem’s severity and the type of floor you have. However, by following these steps, you should be able to get your floors looking like new again in no time! Thanks for reading our post about how to fix uneven polyurethane.

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Adrian Green

Adrian has been interested in woodworking since he was a child. His father had a woodworking shop, and Adrian would help him out and learn from him. He gained basic carpentry knowledge as well as an understanding of how to work hard and take care of business. He enjoys woodworking as a hobby. He loves the feeling of creating something with his own hands, and the satisfaction that comes from seeing his finished products used by others. So he started this blog to spread his passion and knowledge to those interested in DIY wood-working projects. He knows that with a little guidance and practice, anyone can create beautiful pieces of furniture or décor from scratch.

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