Calcium silicate bonded with sodium silicate. Although it is popularly considered an asbestos substitute, early uses of calcium silicate for insulation still made use of asbestos fibers. It is used in passive fire protection and fireproofing as calcium silicate brick or in roof tiles. It is one of the most successful materials in fireproofing in Europe because of regulations and fire safety guidelines for commercial and residential building codes (see Calcium Silicate use in Europe). Where North Americans use spray fireproofing plasters, Europeans are more likely to use cladding made of calcium silicate. High-performance calcium-silicate boards retain their excellent dimensional stability even
Sodium silicate used to make hard, high-temperature insulation boards used for refractories, passive fire protection and high temperature insulations, such as moulded pipe insulation applications. When mixed with finely divided mineral powders, such as vermiculite dust (which is common scrap from the exfoliation process), one can produce high temperature adhesives. The intumescence disappears in the presence of finely divided mineral dust, whereby the waterglass becomes a mere matrix. Waterglass is inexpensive and abundantly available, which makes its use popular in many refractory applications. Sodium silicate solution is used as a fixative for hand dyeing with reactive dyes that require a high pH