Today's building glass configurations are becoming more complicated as the demand for higher energy performance increases. Insulating glass units with Low-E coatings are providing beautiful aesthetics while helping buildings reach energy goals.
With advancements in energy performance, the Glass, Construction and Architecture industries have seen an increase in heat gain around buildings’ spandrel cavities. This heat gain in spandrel areas results in temperature gradients across the glass that may result in breakage of the inboard glass lite.
Considering the design changes, one of the most profound mitigation strategies for combating thermal stress breakage is the use of silicone spandrel opacifying coatings like OPACI-COAT-300®. Why are silicone coatings a mitigation strategy?
It is a well-documented fact that ceramic enamel frit, on heat-strengthened and fully tempered glass, weakens glass up to 40% from expected strengths. The result of this is a heightened risk for thermal stress breakage to occur.
What is thermal stress breakage? It is a type of breakage that manifests due to large thermal differences across a piece of glass. A common example occurs when the morning sun heats up the center of an insulating glass unit with cooler edges. This temperature difference causes tremendous stress. Another example can occur when acute angled shadowing falls across the spandrel cavity. Ceramic enamel frit will lower the threshold of what a heat-strengthened lite will accept before it breaks.
OPACI-COAT-300® does not weaken glass and is one of the most significant facts that contribute to why far less thermal breakage is seen with glass coated by silicone opacifiers. Take a look at recent research conducted to show a comparison of glass weakness in ceramic enamel vs. silicone opacifiers. http://www.icdcoatings.com/silicone-opacifiers-for-risk-mitigation-in-thermal-stresses