Asbestos in homes

Most of Silicon Valley has pre-1978 homes,  and most of them contain some amount of asbestos, commonly on the HVAC ducts and, more visibly, in some popcorn or acoustic ceilings. It can also be in less known areas, such as vinyl flooring or perhaps the glue under the flooring.  Homes built after 1978 are far less likely to be effected. Asbestos can be found in almost any product, especially in older parts of the home where fire retardancy would be beneficial.

Very few people test their for asbestos in homes. Seeing that a seller has “no reports” on items like asbestos or lead on their home is not uncommon, but it does not mean it is not there, particularly in older properties.

Undisturbed asbestos is not supposed to pose a health risk. I know for a fact that my 1977 built home has asbestos on the boots, where the ducts come up to the heat register. Since it is on the external part of the ducting, not the inside, the air in our house should be clean and free from asbestos.

What is it?

Like mold, asbestos is a naturally occurring substance found in some soils, and sometimes mined. (Click on the image below to see a map of sites in California in which there is or is suspected to have asbestos present.) In the San Jose area, it’s known that asbestos was found or mined at the New Almaden Mine and also in the area near Communications Hill where KB Homes built a large subdivision.

Santa Clara County - naturally occuring asbestos

Asbestos is the common name for a group of silicate minerals made of thin, strong fibers, best known for their use as excellent fire retardants. Not many realize that it occurs naturally in certain areas, including California. The most common naturally occurring Asbestos is Chrysotile, often found in serpentine, common to the Sierra foothills and the Coast Ranges.

What does that mean? Since Asbestos are minerals, that means they are generally stable and will not evaporate. However, the mineral can be crushed into a fine dust which will float in air – this is referred to as friable asbestos. Friable asbestos, suspended in air and breathed by humans is a carcinogen linked to the development of lung cancer.

What are the risks of asbestos in homes?

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