REPRINT FROM THE INTEGRAL NEWSLETTER ……….
Unfortunately there are no hard and fast rules that determine when you must test for asbestos in drywall.
In 1972 the manufacturing of products containing asbestos was banned in Canada. However problems ensued with newer drywall compounds manufactured after 1972. Issues included the inadequate adhesion of the compounds to the board. They would flake, crack and virtually fall off the surface of the drywall board, affected by the atmospheric conditions existing around the application.
Manufacturers in North America were allowed to continue to produce and distribute drywall compound with asbestos up until 1980 when this problem was resolved.
After 1972, the raw asbestos stockpiles in North America continued to be sold to the compound manufacturers until the late seventies. These products were sold into Canada during that period even though in 1972 the manufacturing of asbestos products had been banned in Canada.
As of 1980 there was no longer the new manufacture of any asbestos products in North America, but there continued to be the sale of the pre 1980 stock of asbestos drywall compound products that were available in warehouses all over North America.
Extending the sale period was the factor that the drywall compounds of 1980 era were of a dry mixture, not the wet mixture of today. Therefore the shelf life of the dry mixture was virtually endless. The resolution became to set time limitations for the retail sales. 10 years was selected as a reasonable time period and 1990 became the cutoff point.
The easiest segment to target to achieve the elimination of the products was warehousing. The wholesalers controlling the warehouses storing the drywall compounds sold to the drywall contractors and would move the old stock through their systems quite quickly.
The next level was the lumber yards and building materials stores that sold these products to not only the contractor but the building owner as well. Because these box type stores had large warehousing distribution centers, it took a little longer to get rid of the asbestos drywall compound products from this segment.
The most difficult segment were the contractors themselves. They retained products, for example in their shops, and did not dispose of or use up the old hazardous products within the prescribed time period. Included in this segment were the DIY’s who retained and used product beyond the 1990’s.
I recently read an article that talked about asbestos being found in the drywall compound of a full renovation completed in 2001 – 11 years later than 1990. In 2007, when liquidating the stock of a hardware store in Ontario, there was found a supply of asbestos drywall compounds that had been available for sale right up until the liquidation date. There were no written rules regarding the sale and/or storage of these dry mixture compounds which had an unlimited shelf life.
A restoration contractor determining the need to test for asbestos would probably follow these guidelines:
- A building constructed after 1990 would probably not require testing, provided that no major renovation was done after it was originally built.
- A building constructed before 1990 would probably require normal testing.
- If any building has been extensively renovated, remodeled, converted to a different design use, by a large renovation contractor after 1990, it would probably require minimal testing.
- Any building that has been extensively renovated, remodeled, or converted to a different design use before 1990 would probably require normal testing.
- Any building that has been renovated, remodeled, converted to a different use by its owner or a small contractor would probably require normal testing.
Are there any hard and fast parameters to determine when testing should be done for asbestos in drywall compound? Bottom line is that every building should be tested for asbestos regardless of whether restoration, remodeling, or renovation work has been or is going to be done by a contractor or building owner. There is no way to know what dangers lurk hidden behind a wall or floor or even out in the open on the surface in, for instance, an attic or a basement.