The type of window and the installation method used depends on the problem that is being overcome and the construction characteristics of the house. The following problem areas are presented and explained to help you understand the various directions your new window installations might take.
Ultra Violet light fades materials such as wall paper and flooring and breaks down fabrics. Ideally, a window would block the damaging UV rays that cause fading, while letting light pass through. Ordinary clear window glass lets in about 70% of the sun's UV radiation. New varieties of high-performance clear window glass, commonly called "low-e" glazings, provide some protection from UV radiation. Even the best of these, however, still transmit 26% of the damaging UV rays.

Clear Single-Pane 29% Lets in about 90% of visible light; blocks out about 14% NIR
Clear Dual-Pane 44% Lets in about 80% visible light; blocks out about 24% NIR
262/LOWE 84% Reduces light 20% over clear
TINTED 45% Blocks out more visible light than LowE; lets in more heat than LowE
LAMINATED 99.9% Doesn't block out heat; relatively expensive
270 (272) 84-86% Lets in 70-72% visible light; blocks out 59%-63% NIR
366/LOWE 95% Lets in 66% visible light; blocks out 90% of NIR light (Near InfraRed Light)

NIR = Near Infrared Rays - responsible for solar heat gain