Cobblestone - Styrofoam Ceiling Tile (Package of 8 Tiles) Easily Glues directly to Popcorn Ceilings, Stucco, Plywood, Sheetrock, Knock-Down. Paintable with any water-based paints, metallic or non-metallic. Cuts with razor knife Adds sound, heat & cold insulation. Looks like real tin or plaster ceiling, depending on the finish.