With the hit the economy has taken, the use of “spectrally-selective” films has seen a dramatic fall. However, the benefits of such films remains unchanged. Such films block UV light (99%), reduce solar heat and heat build-up, retain heat in winter, all while only reducing the visible light by an amount undetectable to the human eye.
Most commonly used in high-end installations, these films were designed to offer the most heat rejection and fade protection possible, without changing the view through the window.
The industry leaders of these films are V-Kool (V-Kool 70), 3M (Prestige 70), Vista (VS70) and Panorama (HiLite 70). This technological breakthrough was originally developed by V-Kool in 1991, and still manufactures the highest performing spectrally-selective film in the world.
3M had the goal of making spectrally-selective films cheaper, and in some ways, succeeded. There are a couple of caveats: First, the optical clarity, or distortion impediment of Prestige 70 is moderate and adds a waviness to the glass. Some would argue that a film that costs $8-$12/sqft shouldn’t distort the view at all. As for Prestige 70 heat rejection, it is not constant, and on a double-pane installation will only perform between 44%-50% heat rejection, depending on the angle of the sun. Still, for those who want to save a couple bucks per foot, this is a way to go.
Panorama HiLite 70’s distortion impediement is undetectable, and its heat reduction performance on double-pane glass is 51%, but its quality that comes at a higher price than Prestige 70 ($10-14/sqft).
V-Kool 70 ($10-$14/sqft) distortion impediment is undetectable, and offers the highest heat rejection in its class on double-pane glass (56.2%).
The manufacturer names and product ID’s are as follows (In order of performance
from best to worst):
V-Kool: VK70 | 56.2% TSER | 64.4% VLT
Panorama: HiLite 70 | 51% TSER | 64% VLT
Vista: VS70 | 48% TSER | 61% VLT
3M: Prestige 70 | 44% TSER | 61% VLT
(TSER: Total Solar Energy Rejected)
(VLT: Visible Light Transmission)