Asbestos In Drywall
From the late 1950s through the 1980s, manufacturers of building materials sometimes incorporated asbestos in drywall to strengthen the sheets, aid in sound absorption, and improve fire resistance. This practice was abandoned following the 1980s, but a large portion of the building materials used during construction during that time period now pose potential health risks.
A much greater risk of exposure to fibers exists in the potential presence of asbestos in joint compound. While modern joint compound does not contain asbestos, compounds used during the 50s through the 80s often did. The sanding process necessary to smooth out taped and spackled joints creates large amounts of airborne dust, creating the perfect conditions for inhalation of the asbestos fibers into the respiratory tract and lungs. For this reason, professional drywall installers have historically suffered some of the highest rates of mesothelioma from long-term exposure to the dust.
Due to encapsulation, a paper covering, and layers of paint and/or wallpaper, the risk of asbestos fiber inhalation from existing walls is extremely low. Dangers arise primarily during demolition and remodeling activities. When repairing cracks and holes in existing walls, care must be taken when sanding areas where the gypsum core of the drywall or patches of bare joint compound are exposed. Because most cracks occur at joints, asbestos in drywall compound can become airborne easily if the crack is sanded deeply enough to remove the paint or wallpaper completely.
Unfortunately, it is impossible to distinguish by visual inspection alone between drywall with asbestos and drywall without. Even modern wallboard contains reinforcing fibers, though they are now generally made of cellulose or fiberglass instead. Asbestos in joint compound is also virtually undetectable with visual inspection. Only a professional test can determine for sure whether or not there is contamination present.
Whenever dealing with construction materials of unknown age or composition, always follow this helpful rule of thumb from the EPA:
If in doubt, treat the material as if it contains asbestos or have it sampled and analyzed by a qualified professional.
Don’t disturb, damage, or attempt to remove questionable materials in any way, as doing so can actually create more of a hazard than simply leaving the material in place. Seek professional help in analyzing the material, and always hire an asbestos abatement specialist if contaminated materials need to be removed.