How to Paint over Polyurethane?

Image of a Surface Being Painted

Polyurethane is a kind of liquid plastic varnish that is used as a topcoat over wooden surfaces for enhancing their protection and durability. If you want to renew your old furniture by painting it, you can’t directly paint on top of polyurethane-coated furniture. Now the question arises in your mind “How to paint over Polyurethane” or “Can Polyurethane be painted over?”.

The answer to your questions is an “A Big Yes”, you can paint on the top of polyurethane. But. you need to do a series of steps for the painting over a polyurethane-coated surface. First of all, clean the wooden surface and free it from dust then fills the cracks anywhere on the surface. Then you need to sand off the surface and apply primer so that the paint adheres over the surface properly.

Now your wooden surface is ready for painting.

Steps Involved In Painting Over Polyurethane 

The steps involved in the painting over the polyurethane surface are described below in detail.

  • Sanding the Surface

For sanding the wooden surface, you first need to clean and wipe it properly to make it free from dirt, grime, dust, or any stains. Few people don’t want to invest their efforts in sanding as they find it a quiet mess.

However, you need to sand the wooden surface to take off the layer of polyurethane up to a greater extent. If you don't sand the surface, the paint won’t adhere to the surface properly and you won’t achieve a good new finish for your wooden furniture.

At first, you need to use heavy grit sandpaper to rough up the polyurethane-coated surface as much as you can. Afterward, you can use slightly lighter grit sandpapers to smoothen up the surface from the scratches caused by the heavy grit paper.

You can also use the palm sander instead of the handheld grit paper but it won’t provide you with the fine finish around the edges as you get from the hand-held sandpaper. So, you need to do a little effort if you want a clean finish paint over the polyurethane-coated furniture. 

  • De-Glossing the Surface

After sanding the wooden surface and freeing it from the polyurethane up to a greater extent, the next step is the de-glossing of the surface. If you are going to apply de-glosser over the surface, you won’t have to do excessive efforts in sanding the surface because the de-glosser is also known as liquid sandpaper.

However, the application of de-glosser is a sensitive task. You need to take proper preventive measures to save yourself from its harmful aspects. It is a strong chemical, and the fumes arising from it can damage your eyes and lungs. Therefore, you need to wear proper protection gear (eyeglasses, a protection suit for skin protection, and a mask).

While dealing with the de-glosser, you need to work in an airy place because ventilation is very important to take its fumes away from you. For the application of de-glosser, dip a lint-free piece of cloth in it and rub it all over the wooden surface and let it air-dry. Also, wear gloves to protect your hands.

  • Primer Application

Primer is applied on the wooden surface so that the paint layer goes smoothly over it. Apply a thin coat of primer and let it dry. Here is an important point for you to note down. After drying the first primer layer lightly sand the surface and then apply the second primer layer; it will help the paint to attach strongly to the wooden surface and give a smooth finish.

Primer plays a vital role in giving an even paint finish just as you want. You can apply primer with the help of a brush.

  • Final Application - Paint the Surface

After you are done with all the steps involved in the preparation of polyurethane coated surface, your wooden furniture is ready for taking up its final coat i.e., paint. Before painting the surface, check that the surface is dust free and dry from all the previous coats. You can use a dry lint-free piece of cloth to clean the surface and make sure that it is now dust-free.

Take a fine paintbrush and apply the first coat of paint. Let it dry and then you can apply more coats to reach the color and finish of the furniture as you want it. Keep in mind that after the first coat, let it dry for at least 72 hours before the second coat. Even if it gets dry, must wait for 72 hours before the 2nd coat if you want a smooth and shiny finish to your furniture.

In this way, the paint won’t get thicker anywhere and you will get the even and best results in the end.

Kinds of Paint that Stick On Polyurethane

The most popular paint options for painting over polyurethane-coated surfaces include:

  • Latex Paint

The latex paint will only stick on the top of the polyurethane-coated surface if it is prepared properly with all the preparation steps mentioned above such as sanding, de-glossing, and priming of the surface before painting over polyurethane. You need to use a primer that has compatibility with the latex paint.

  • Water-Based Paint

Water-based paints will go on the surface of polyurethane if you prepare the surface very well and use an oil-based primer having the right compatibility with the water-based paints.

  • Oil-Based Paint

Oil-based paint is a good option for painting over polyurethane surfaces because polyurethane is oil-based itself. Therefore, you don’t need a special kind of primer and the oil-based paint goes very well on top of polyurethane-coated surfaces. 

  • Acrylic Paint

For acrylic paints, you need to first confirm if the paint is water-based or oil-based. If the paint is water-based, it requires an oil-based primer and if the paint is oil-based, it will go well with the water-based primer.

  • Enamel Paint 

Enamel paint is a great choice for painting over the polyurethane surface. It needs oil-based primer after all other preparations. It is durable as compared to the other paint options.

  • Chalk Paint

The sanding and priming of the surface are the important steps for the application of chalk paint. The chalk paint is water-based so oil-based primer is a better option for it.

  • Spray Paint

The spray paint over polyurethane is always the best option. If the surface is prepared properly, it goes well with the oil-based primer. However, painting over polyurethane-coated surfaces is a sensitive and time-taking job. It is better if you look for professional and affordable paint services. For finding the best professional painting companies in no time visit CityLocal101