During most of the 20th century, thermal insulators as well as decorative acoustic material contained asbestos. While its main use was as a material for insulating, asbestos was used for a number of things in construction, including as an ingredient in troweled coatings that were meant as insulation for both walls and ceilings. When sprayed on or troweled on, coatings that contained asbestos presented a definite danger to those who faced exposure.
Troweled on coatings with asbestos are possibly better known as “popcorn ceilings” or “cottage cheese ceilings”. These were decorative textured coatings that were popular from the 1950s through the 1970s. These coatings often contained asbestos until 1978 when the EPA banned them.
This use of asbestos is likely one of the most hazardous that there is. Removing it is nearly impossible to do without asbestos dust permeating the air. This also makes the renovation or demolition of buildings with asbestos trowel coating hazardous as well. The asbestos fibers that make up the dust can result in mesothelioma, a cancer that affects the lining of vital organs like the lungs, heart, and abdomen.