The choice of correct glazing must take into consideration thermal insulation (winter and summer), acoustic insulation and safety features.
The performance and efficiency of glass in winter is represented by its Ug value: the lower the value the better insulator the glass is and the more money you save on heating bills. By combining more interspaces, using low-E glass, and including noble gases such as argon and krypton, glass thermal insulation characteristics can reach Ug values as low as 0.5: ten times better insulating performance than a single pane of 4 mm-thick glass!
Summer performance efficiency is given by glass’s ability to insulate from solar radiation in the summer months and is expressed by its solar factor SF. The lower the value, the more efficient the glass is at regulating the sun’s energy. Acoustic insulation is defined with the reduction value of the external noise Rw expressed in decibels dB. A higher Rw value expresses a higher acoustic insulation capacity.
Italian Ministerial Decree of 5/12/97 establishes the limits to be met based on the intended use.