LSG Calculator

LSG measures how much visible light a glass admits relative to the amount of solar heat it allows to enter. In a single number, it reveals the balance between daylight performance and solar control. The higher the LSG, the more effectively a glazing system delivers natural light while limiting unwanted heat gain.
For designers and consultants, LSG provides a straightforward way to identify glazing products that offer the best of both worlds — brighter interiors, improved occupant comfort, reduced dependence on artificial lighting, and lower solar heat gains. Rather than evaluating multiple performance values separately, professionals can use LSG as a quick indicator of overall glazing efficiency and spectral selectivity.