Asbestos was popular among home builders and manufacturers in the mid and late 1900's.  Widely used for its affordability and its resistance to fire, heat, electrical and chemical damage.  Asbestos was commonly used in electrical insulation and as an application for the exterior of heating ducts.  When asbestos fibers are airborne, they can cause serious illness, so it is recommended that any asbestos in your home is encapsulated or removed.  If you are looking at a property to purchase, do not be alarmed if you learn that the house contains asbestos, as I have first hand witnessed hundreds of homes with asbestos ducting.  Every homeowner is different and you may opt to encapsulate the asbestos or remove it.

After living in a 1951 home with the original heating ducts intact that contained asbestos, I finally had the ducts removed when I replaced my furnace. The process entailed several guys from Synergy taking  great care to tape off the the area surrounding the ducts that they were removing to ensure that no fibers would penetrate my home.  After a FULL day of hauling 21 long ducts out of my home, they came back to check the air quality to ensure the asbestos levels were safe.  The cost was $1500.