The Efficient Windows Collaborative: Benefits

Benefits: Increased Light & View

Daylight and view are two of the fundamental attributes of a window. Unfortunately, windows are also the source of significant solar heat gain during times when it is unwanted. Traditional solutions to reducing solar heat gain such as tinted glazing or shades mean that the amount of light is reduced as well. New glazings with low-solar-gain Low-E (spectrally selective) coatings can provide better solar heat gain reduction than tinted glass, with a minimal loss of visible light. This also means that views can be clearer and unobstructed.

Performance of Double-Glazed Low-Solar-Gain Low-E Glass (Spectrally Selective) and Argon Gas Fill

Solar Heat Gain and Visible Transmittance

Note: All values are for glass only without frame. Source: Residential Windows by Carmody, Selkowitz, Arasteh and Heschong, 2000.

	Window A Clear, Single Glazing SHGC=0.86 VT=0.90
	Window B Bronze/Gray Tint, Single Glazing SHGC=0.73 VT=0.68
	Window C Clear, Double Glazing SHGC=0.76 VT=0.81
	Window D Bronze/Gray Tint, Double Glazing SHGC=0.62 VT=0.62
	Window E High-Performance Tint, Double Glazing SHGC=0.48 VT=0.69
	Window F High-solar-gain Low-E, Double Glazing SHGC=0.71 VT=0.75
	Window G Moderate-solar-gain Low-E, Double Glazing SHGC=0.53 VT=0.75
	Window H Low-solar-gain Low-E, Double Glazing SHGC=0.39 VT=0.70
	Window I Moderate-solar-gain Low-E, Triple Glazing SHGC=0.50 VT=0.65
	Window J Low-solar-gain Low-E, Triple Glazing SHGC=0.33 VT=0.56

Energy and Cost Savings | Improved Comfort | Less Condensation
Increased Light and View | Reduced Fading | Lower HVAC Costs