How to Paint Plywood Subfloors
- 1). Fill all nail holes in the floor with wood putty using a putty knife to press it in. Caulk all cracks between the different sheets of plywood using a caulking gun. Allow the wood putty and caulk to dry for 24 hours.
- 2). Open all windows and doors and set up a floor fan to provide cross-ventilation. Put on a dust mask and sand all wood puttied spots and any rough or high spots on the floor using an electric orbital sander with 100-grit orbital sanding papers. Sand these spots until the floor is relatively smooth.
- 3). Sweep and vacuum the floor to remove all dust and debris.
- 4). Put on a paint respirator and turn on the floor fan. Open a can of oil-based wood primer with a flathead screwdriver and dip the bristles of a 3-inch wide paintbrush into it until about 1-inch of the brushes bristles are soaked with paint. Paint a 6-inch border around the floor where it meets with the walls. Use a mini roller to help apply this border.
- 5). Pour a 1/2-gallon of the primer into a paint tray and then slide a 1/2-inch nap roller cover over the spindle of a 9-inch paint roller frame. Screw an extension pole into the handle of the roller frame. Dip the roller into the primer paint until the nap fibers are soaked with paint and then walk to the side of the room furthest from the exit.
- 6). Set the roller down in the corner so that it overlaps the previously painted boarder by 2-inches and then roll along the border until the roller needs to be dipped in the paint again. Re-dip the roller and then roll some more. Roll a 4-square-foot area of floor at a time in zig-zag patters. Use the up and down zig-zag patterns to even out the paint and roll out all roller track marks or lap lines. Roll the entire floor and work continuously to the exit door so that you avoid painting yourself into a corner. Allow the primer paint to dry for 24 hours.
- 7). Apply a coat of oil-based finish paint over the coat of primer paint by painting the border first and then rolling the floor the same way the primer paint was applied. Wait 72 hours before walking on it.
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