How to Spray Polyurethane?

One of the popular materials used for wood finishing and floor finishing is the Polyurethane. This is used as a shielded coating for a number of projects like wooden projects. The reason for using this material for wooden and floor finishing is it provides high durability and hard gloss for the surface. Another reason for using this is the paints made with polyurethane can be applied to any type of surface.

One of the general questions arises to many users while using this material for painting is how to spray Polyurethane? In general, there are various kinds of this material available in the market. Based on the formulation of this compound and some other factors spraying polyurethane varies. As it is available in different types, spraying this material also differs. The forecast use and the size of the project fix the best method of application and type of finish.

Spraying this material depends on the surface for which it is used for, the formulation used with it water or spills, exposure of the sunlight etc. Based on these the uses of polyurethane also change. It serves as a good heat resistant which makes it as a good kitchen furniture coat. Another question related to this spraying is whether it can be sprayed perfectly or not. It is a coating material which is normally used to protect wooden surfaces. Once used it offers a number of benefits to the user and that’s the reason why most of the people consider polyurethane for their wooden coating.

Water Based Polyurethane vs Oil-Based Polyurethane

Waterbased vs OilbasedBefore going to apply polyurethane for the surface and know how to spray this material, first we have to decide which type polyurethane is best, water based or oil based? Both type of polyurethane are best in its own way and exhibit different qualities. Both types are highly durable and offers good look to the surface but there are some differences between them. You have to choose the right one for your project

Drying Time

The first difference between these two types is the drying time. Water based polyurethanes take a less time to dry, on the other hand, oil based polyurethanes take quite much time to dry. Once sprayed, the water based polyurethanes take two hours and you can recoat them and clean with water. Even you can sleep in the room overnight. But, the oil based polyurethane take five to twelve hours to dry. This is a long time and you can use your room only after this time

Finished Effect

The next factor to consider is the finishing effect. When comparing these two, the polyurethanes based on water won’t give a good finish to the surface. Whereas the polyurethanes made with oil give an amber glow to the surface. Also, the water based polyurethanes give a perfect finish on its final coat. While oil based polyurethane requires fewer coats for a final finish. Thus, at the finishing point the oil based polyurethanes are best than the water based one.

Working Environment

Working EnvironmentThe working environment for these two types also differs. As the water based Polyurethanes dry quickly one can use this in any working environment. The oil based polyurethanes take much time to dry, therefore, one should in a working environment that should be clean and dirt or bugs free. This is because if the working environment is not clean in the case of oil based polyurethane then, as the time goes the bugs and dusts get stick to the surface. This will affect the quality of the work and finish.


After spraying, the water based polyurethanes need two or three touchups. That is after drying you need to give another coat to the surface in order to achieve a good finish. But, oil based polyurethanes are best in this aspect. It gives a good glow and look to the surface on its first coat and it does not require any additional coats. Fewer coats are enough in the case of oil based polyurethanes.

Touch-upsThe water based polyurethanes has only 30 to 35 solid percent of solids, whereas the oil based polyurethanes contains 45 percent to 50 solids. Therefore, water based polyurethanes need extra coats when as it contains small solid percent. This is because these solids are the factors that give a good protective finish.


The most important one to consider is the cost. When coming to the price, water based polyurethanes cost more than the oil based one. The cost of water based polyurethanes is twice more than the cost of oil based. Therefore, if you are money concern you can go for oil based polyurethanes

Long Lasting

The polyurethanes based on the water lasts for a long time than the oil based ones. This is because as these polyurethanes require more coats than oil based one, it has a long life. Whereas, the oil based polyurethanes need only fewer coats and fade soon.

Tools and materials

Following are the tools and materials needed for this project

Tools and materialsTools needed

Before going to start your spray you need necessary tools. This will help you to avoid frustration at the time of painting and it will save your time to a greater extent. The tools needed for spraying this polyurethane are

  • Roller tray
  • Rags
  • Floor finish applicator and
  • Knee pads

In the case of polyurethanes based on oil you need a brush with a fine bristles and a foam brush and clean cloth.

Materials needed

Like the tools you also need to make arrangements for you materials also. The following materials are needed

  • Polyurethane
  • In the case of polyurethanes based on oil paint thinner is required

How to spray polyurethane paint?

So far we have seen about polyurethanes, its type and which one is better water based one or oil based one. Now we are moving into the spray. Let us see how to spray polyurethane paint. This step by step guide will be very useful for you if you are in need of spraying polyurethane paint for your wooden painting project or any other surface painting project. Follow the below given steps

Step 1: Set up the work area

Set up the work areaThe first and foremost step you need to do is to set up your work area. Make arrangements for the area on which you are going to work. You have to concentrate on your working area whether it is clean or not. A clean working area is needed for spraying this material. Also, keep all the things needed at the time of spraying nearer to you but not so nearest. This will be very helpful for you at the time of painting

Step 2: Surface preparation

preparationAfter setting up the working area, you need to prepare the surface on which you are going to spray your polyurethane paint. Keep the surface area clean and dirt free. If there is any dust or bugs on the surface then you can’t able to get the perfect finish. It is better to clean the surface area with a neat cloth before spraying. This will remove any dust or dirt on the surface and the paint will sits perfectly on the surface. Keep in mind that a well cleaned surface is must

Step 3: Spraying

SprayingBefore starting your spray, prepare the spraying material correctly. As polyurethanes need thicker coats, you need the help of thinner. But, first spray the paint without using thinner and see the finish. Based on the finish consider whether you need to add thinner or not and then add it.

In order to attain good finish, you have to spray the paint in thinner coats. This is because thinner coats will give a good finish and removes ruins. Between your coats, sand the surface. This will provide a surface for the next round of coat. Spray a number of thins coats and this will give the thicker coat that you want to achieve

Step 4: Drying and Cleaning

Drying and CleaningAfter successfully spraying your paint, allow it to dry. Let it take some time to dry. Once the surface is dried, clean your surface with water. If you use oil based polyurethanes it take quite a much time to dry. Hence, check once the surface is dry or not and then clean the surface.

Tips for safely spraying polyurethane

  • While spraying polyurethane on vertical surfaces, you need to be careful of runs and drips.
  • It is better to spray thinner coats on these types of surface
  • Even though you face a run, you have to handle this with extra care.
  • Use some sharp razor blades to remove this run and to achieve a clean finish
  • Before starting your spray, be prepare with all the safety measures
  • Also, while applying the paint you have to look in different angles. This will help you achieve perfect finish
  • Always do your painting work in a clear light and stand in the reflective direction of the surface and look in various angles
  • This will help you identify your areas that are missed and over brushed. Hence, you can correct that areas and attain a perfect finish


On the whole, if you want to achieve a perfect polyurethane finish for your surface, you have to concentrate on all the above mentioned factors. Starting from the type of polyurethane to the surface are you need to concentrate each and everything. Then only you will be able to attain the productivity on your painting project. Thus, clearly arrange all the needed things, make your spray, pat it dry, recoat it, and finally clean your surface and enjoy it.