Thermal stresses and cracking in absorptive solar glazing

The emerging popularity of absorptive, as opposed to reflective, solar glazing coatings on windows has generated renewed interest in thermally induced cracking of glass structures. Here we analyse the stresses on glass coated with absorptive solar glazing films caused by uneven solar illumination. It is shown that the occasionally reported brittle fracture of such structures can be readily explained as being the result of differential thermal expansion of the glass. The magnitude of the effect is linearly proportional to the shading coefficient of the glass and is also influenced by the manner in which the glass is supported.