Free Mesothelioma Information Packet

Calcium Silicate Insulation

Today, calcium silicate insulation is widely used in construction as a material to insulate and protect against fire and excessive heat, as well as to dampen sound and add insulation to existing and new structures in both residential and commercial construction applications. In addition, the material has often been used in the manufacture of steam boilers and ductwork, as well as in materials used to insulate water and steam pipes. Steam pipes have often been surrounded by calcium silicate products to add insulation, prevent heat buildup and escape, and to join pipe to other components of the steam system.

Calcium silicate insulation and asbestos

Until the mid-1970s, asbestos was popularly touted as a “wonder fiber,” known for its amazing variety of uses and applications within the construction and manufacturing industries. Flexible yet strong, resistant to both heat and corrosion, and widely and inexpensively available, it’s no wonder that so many manufacturers, engineers, and builders turned again and again to this fiber-like material as the answer to their construction and design needs.

And it was due to the high heat resistance and insulative properties of asbestos that it became an integral component in the widely used calcium silicate insulation material. Calcium silicate insulation is one of the most widely used materials in the building industry. And although regulatory practices halted the manufacture of construction products which contained asbestos in 1977, many of the existing supplies were used well into the next decade. As a result, there’s a good chance that any residential or commercial building constructed prior to the mid-1980s has calcium silicate insulation in one or more of its components, either as an insulator in heating systems or as insulating sheets between walls or ceilings.

Certainly, construction workers, HVAC specialists, and those involved in the manufacture of the product have undoubtedly been exposed to the dangers of asbestos. But the risks don’t stop there. Like other construction materials which contain asbestos, the asbestos contained in calcium silicate insulation, when left undisturbed and in its pristine, original form, is not harmful. But when disturbed during building renovations or upgrades to a new, more efficient heating system – even during annual duct cleaning – the degraded, brittle asbestos fibers can easily become dislodged, forming a fine dust which is easily inhaled.

Last modified: December 28, 2010.