How to Paint an Oriented Strand Board

What You'll Need
Oil-based paint
Stain blocking primer
Paint trays
Latex top coat

An oriented strand board (OSB) is used in walls as a sheathing. This is an engineered wood product and may also be used on floors and roofs. Much cheaper than plywood, OSB has no internal gaps and is therefore much preferred. Most manufacturers also put a water resistant film on the OSB because of which it becomes more durable. Also, addition of boric compounds makes it toxic to termites and other wood boring pests. A lot of people prefer this product because it can be easily screwed in and removed from the wall, floor or roof surfaces.

OSB is also considered environment-friendly because it is made up of veneers of wood, making the surface variegated. This makes the OSB extremely difficult to paint. As compared to painting plywood, painting OSB boards can be much of a challenge. However, it is not completely impossible. Here’s how you can paint an OSB.

Step 1 – Applying the First Coat

Regular primers just make the paint bleed from the OSB, and therefore, OSBs cannot be painted in the way normal plywood is painted. Hence, you should choose the right kind of oil-based paint. You can use water based paints too; however, these will bleed more quickly and leave the OSB looking extremely unattractive. Water paints also require regular maintenance because the paints would peel easily. After you have chosen an oil paint of your choice of color, apply the first coat to the OSB and allow it to dry.

Step 2 – Choosing the Best Primer

Stain blocking primers are the best for OSB painting. This is because the acrylic latex compound in the primer allows it to hide the stains and prevent bleeding of paint. This is excellent for sealing the first coat of oil paint that you have put. After the first coat has dried sufficiently, apply a single coat of the primer. You may also apply a thick layer of block filler primer on top of the first layer of primer. This helps to fill in any gaps in the layers of the wood and gives the OSB a smoother finish.

Step 3 – Finishing with the Top Coat

Even after the primer has been applied and dried, you may still see some stains on the OSB. To remove these, apply a final top coat of latex paint. Allow the paint to dry out completely. If there are still some marks that are visible, this will help cover them all. You can apply another top coat on the OSB after the first coat has dried. The top coat not only seals the primer and the paint but also gives a glossy finish to the boards, making it perfect to be used on the walls. Apart from this, the top coat also allows the paint to stay for longer, preventing it from fading due to weather conditions and leeching. The top coat makes the color last long and also protects your wall surfaces from getting dirty since dust and grime can be cleaned off easily.