Highly recommend this product. I knew they were styrofoam but was surprised at how thin they were, but with some chalk lines and loctite adhesive, a local handyman was able to hang them through our living room and dining room (my husband and I decided we will do this ourselves to our bedrooms, but the intricacies and size plus wanted new crown molding, so we hired someone for downstairs instal) We are putting these right over old cardboard tiles from the 60s. I do recommend painting them (we went with a cream) as they have a glossy Styrofoam look, but not “bad” unpainted.