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Glass Technology

Learn about Low-E coatings, insulated glass units, argon fill, and advanced glazing options for optimal performance.

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Low-E Coating Types: Low-E2 vs Low-E3 vs Low-E4

Compare Low-E coating technologies optimized for different climates and energy goals.

FeatureLow-E2 (Passive)Low-E3 (Solar Control)Low-E4 (Advanced)
Primary PurposeKeep heat IN (cold)Keep heat OUT (hot)Balance heating/cooling
SHGC (Solar Heat Gain)0.40 - 0.55 (higher)0.20 - 0.30 (lower)0.25 - 0.35 (moderate)
U-Factor (Insulation)0.28 - 0.32 (good)0.28 - 0.32 (good)0.22 - 0.28 (excellent)
Best Climate ZonesZones 4-8 (cold)Zones 1-3 (hot)Zone 4 (mixed)
Ideal ForHeating-dominated (Boise, Denver)Cooling-dominated (Vegas, Phoenix)Four-season (Seattle, Portland)
Cost Premium+$50-$75 per window+$50-$75 per window+$75-$100 per window
Light Transmission70-80% (bright)60-70% (slightly tinted)65-75% (balanced)

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