Hidden treasure ceiling tile from A La Maison Ceilings collection offers a beautiful Victorian design. It can be glued over most stable ceiling surfaces including popcorn ceilings and painted to your likeness. The tiles are made from extruded polystyrene. The size is 19-5/8 in. x 19-5/8 in. coverage is 21.6 sq. Ft. Per pack. Depth of the design is 1/4 in. these tiles will add beauty, sound dampening and insulation.