Asbestos Cement Siding

Asbestos Cement Siding


Asbestos cement siding is most commonly seen as rectangular shingles measuring about 18 by 24 inches. It is also seen as horizontal lap siding. Finishes include smooth and textured. Thickness is about ⅛ inch. It was installed by fastening siding to sheathed walls, preferably over a water-resistive barrier. It was first available in the early 1900s and was most popular from 1920s to 1950s.

Asbestos was banned in most building products in 1973. This siding is no longer available, but some fiber cement siding manufacturers produce products that mimic some common types of asbestos cement siding. More information about asbestos products is available at:

Inspection for and reporting of hazardous materials, such as asbestos, is out of scope of a home inspection. Most home inspectors, however, report the presence of suspected asbestos containing materials and recommend that the materials be tested to determine if asbestos is present. Asbestos abatement and containment protocols must be followed during cutting, sanding, and removal; these procedures can be costly.

Typical Defects Typical defects that home inspectors should report include:

  1. absent and deteriorated flashing and sealant around doors, windows, and other penetrations,
  2. absent and improperly installed flashing and kick out flashing at wall intersections,
  3. damaged and deteriorated siding and trim,
  4. fading or pealing finish,

Safety Issues Asbestos is a known carcinogen when inhaled or ingested. Asbestos is not a safety issue when intact and not frieable (airborne).


Image caption reads "Typical Asbestos Cement Siding with Significant Damage."