How to Paint Oriented Strand Board

A close-up image of oriented strand board.
  • 1-3 hours
  • Beginner
  • 50-75
What You'll Need
Stain-blocking primer
Oil-based paint in your choice of color
Rollers
Paint trays
What You'll Need
Stain-blocking primer
Oil-based paint in your choice of color
Rollers
Paint trays

OSB, or oriented strand board, is an engineered wood product often used as sheathing in walls, floors, and roofs. It is cheaper than plywood and, with no internal gaps, more rigid. Manufacturers of OSB often cover it with a water-resistant film and add borate compounds to the wood, making it toxic to insects like termites and wood-boring beetles.

Many people prefer OSB to plywood or other alternatives as it is easy to remove and screw into, as well as more environment-friendly. It’s formed by layering strands of wood, which forms a variegated surface making it hard and frustrating to paint properly. Although difficult compared to painting plywood, it is not impossible, and many DIY fans have found different ways of performing the task.

Step 1 – Choose the Best Primer

Prolonged moisture exposure to OSB can cause the wood fibers to lift and separate, destroying your paint job. Primer is essential to eliminating that potential problem for a much more professional look. Acrylic latex stain-blocking primer will hide any stains on the OSB. This also seals the paint and prevents any bleed-through. Use a block-filler primer to fill in the gaps between strands of wood, thereby giving it a smoother look. Apply two coats of primer and allow it to dry completely before painting.

Step 2 – Pick the Right Paint

Using oil-based paint is essential. Just painting the OSB like you would paint plywood will leave the OSB rougher and the paint will bleed through regular primer, while using water-based paint causes the OSB to peel over time, making it look unattractive and requiring regular maintenance.

Step 3 – Apply the Top Coat

Apply a top coat of oil-based paint in the color of your choice and allow it to dry. Repeat the process. In the end, you will have a beautifully painted OSB wall, roof, or floor that should last a long time.

Since the 1990s, oriented strand board has proven to be an economical and competitive structural panel, its production far exceeding that of plywood. Pound for pound, it is stronger than steel and concrete, and unlike those, it is made from a completely renewable resource. Due to its low impact on the environment, high availability, and low cost, it is a great alternative to plywood.