Are all Low Emissivity (Low-E) coatings the same?
There are two methods used to manufacture low-e glass, pyrolytic deposition and vacuum deposition. The difference between the two is the pyrolytic deposition method applies the coating to molten glass during the manufacturing process. Vacuum deposition, on the other hand, applies the coating to finished glass in a large vacuum chamber. Specific to vacuum deposition, expanded flexibility exists to apply the low-e coating to a variety of tinted glass substrates. Frequently the combination of a low-e coating and tinted glass require heat-treating due to increased thermal stresses associated with such combinations and should be reviewed during the design stage. Post heat-treatable low-e coatings are offered in the market today that allow fabrication and heat-treatment after the vacuum deposition of the coating. In general, a greater offering of low-e coatings in combination with colored glass options are available with the vacuum deposition process conducted after heat-treating is complete
