Before the 1980s, many homes had siding manufactured from composite cement that contained asbestos. This siding was made to look like shingles or panels, and was attached to the outer walls of the house. Asbestos was used in the cement composite, as it was known for its ability to resist high temperatures. Ideal for stopping the spread of fires, the siding also acted to insulate the home and keep heat in. Today, siding is often manufactured from vinyl or composite cement panels that do not contain asbestos.
Asbestos Rule #1: If it Ain’t Broke, You Probably Shouldn’t Fix It
If you have vinyl siding over asbestos siding and the siding remains in good condition, consider the Consumer Product Safety Commission’s advice: “If you think asbestos may be in your home, don’t panic! Usually the best thing is to LEAVE asbestos material that is in good condition ALONE.” Vinyl siding installation may involve drilling, screwing, or nailing objects into the existing siding, creating an exposure hazard where none may have existed before.
Asbestos is most dangerous when it is friable, meaning that it crumbles easily. Generally, asbestos found in siding is not considered to be friable unless it has been damaged in some way, causing small fibers to be released into the air where they can be inhaled.
Asbestos fibers can also be carried on hair and clothing, where they may be inhaled by other people who have close contact with the person carrying the fibers. These tiny fibers settle inside the linings of the lungs, where they cause changes to occur and disease to develop over a period of time.
Asbestos siding that is not damaged is generally not considered to be friable. If the asbestos siding on your home is damaged from normal erosion, repair work, or has been drilled for any reason, consult an asbestos inspector and/or licensed asbestos professional immediately. Do not attempt to remove or otherwise disturb the siding.
If you would like to freshen up the look of your old asbestos siding, consider adding a fresh coat of paint. Before you begin however, remember that you cannot sand, chip, or otherwise disturb the material. The Puget Sound Clean Air Agency cautions against aggressive power washing prior to painting: “If the washing abrades the surface, breaks, or otherwise disturbs the siding, then the project becomes subject to the asbestos regulatory requirements.”
Vinyl Siding Over Asbestos Siding: Protect your home by exercising caution
Although you may be tempted to simply cover vinyl siding over asbestos siding, consider that in doing so you may create an exposure hazard where none had existed before. If you discover damaged asbestos siding, do not undertake repair or removal on your own. Most states offer some type of formal certification for asbestos inspectors, as well as contractors who specialize in asbestos abatement (removal and encapsulation). Check with your state to find a properly licensed contractor in your area.