Don't use a nylon brush, as this will leave flaws in the finish.
If you would like to paint Styrofoam ceiling tiles, consider a couple of critical points before you get started. Certain types of paint will melt Styrofoam surfaces. Select the appropriate base and finish coat, or you may permanently damage the ceiling. Many times, Styrofoam ceilings tiles are hung within a metal frame. Unfortunately, metallic surfaces require a special acidic base coat before they will accept a painted finish. Prepare each surface in the appropriate manner, or your final finish may flake and fall to the ground.
Instructions
1. Clear all items from the room.
2. Dust the Styrofoam ceiling tiles with a broom.
3. Line the tops of walls adjacent to the Styrofoam ceiling tiles with professional painter's tape. Cover the floor with fabric drop cloths.
4. Fill a 1-gallon painter's pot to one-quarter capacity with metal self-etching primer. Use a polyester paintbrush to apply etching primer to the exposed metal frame between each tile. Wait three hours for the frame to dry. Skip this step if there is no frame. Wash the brush with water.
