Popcorn ceilings, more accurately called acoustic ceilings, are a spray-on or paint-on texture that was used to finish drywall in residential construction between the 1950s and 1980s. The textured material was first made of a mixture of styrofoam and white asbestos fibers. In 1978 the use of asbestos was banned because of the negative effects it was found to have on a person’s health (shortness of breath, mesothelioma, lung cancer). Since then, the material is primarily made of paper-based styrofoam.
To apply the texture, builders would add the mixture with water and stir until it had a cottage cheese texture. Once the walls or ceilings were cleaned and primed, they would spray the mixture on and in some cases would apply a coat of paint over the texture.
Popcorn texture was used for a quick finishing technique to cover imperfections and create better acoustics in the room it was applied.