Glass Performance Specs

Glass Weight Per Square Foot
Glass Thickness LBS
3/32 Single Strength (2.2 mm) 1.21
1/8 Double Strength (3.0 mm) 1.69
5/32 (3.9 mm) 2.43
3/16 (4.7 mm) 2.51
1/4 (5.7 mm) 3.23
3/8 (10.0 mm) 4.78
1/2 (12.0 mm) 6.36
3/4 (19.0 mm) 9.1
Approximate Load Limits on Glass Shelved LBS/Square Feet
Distance in Feet Between Supports
Glass Thickness 1′ 2′ 3′ 4′ 5′
1/4 73 16 5 2 N/A
3/8 196 45 17 8 3
1/2 345 81 33 15 7
3/4 817 197 82 42 23
Insulating Glass Wind Load Restrictions
Annealed Glass Maximum Area in Square Feet: 40 LBS Per Square Foot
Glass Thickness Aspect Ratio less than or equal to 2 Aspect Ratio greater than 2 Maximum Length (inches)
3/32 Single Strength (2mm) 10 8 72
1/8 Single Strength (3mm) 15 13 84
5/32 Single Strength (4mm) 24 20 96
3/16 Single Strength (5mm) 33 27 140
1/4 Single Strength (6mm) 45 37 142
Insulating Glass Wind Load Restrictions
Heat Treated Glass Maximum Area in Square Feet: 40 LBS Per Square Foot
Glass Thickness Aspect Ratio less than or equal to 2 Aspect Ratio greater than 2 Maximum Length (inches)
1/8 Single Strength (3.1mm) 22 20 84
5/32 Single Strength (3.9mm) 30 30 96
3/16 Single Strength (4.7mm) 50 50 140
1/4 Single Strength (5.7mm) 60 60 142
Cardinal Low-E Performance Data
3/4″ Double Pane Visible Light Transmittance Solar Heat Gain Coefficient U Factor (Air) U Factor (Argon)
Clear / Clear 81% 0.76 0.48 N/A
LoĒ²-240 (#2) / Clear 40% 0.25 0.3 0.26
LoĒ²-270 (#2) / Clear 70% 0.37 0.30 0.25
LoĒ²-272 (#2) / Clear 72% 0.41 0.30 0.25
Clear / Pyrolitic LOW E #3 75% 0.72 0.33 0.29
1″ Triple Pane Visible Light Transmittance Solar Heat Gain Coefficient U Factor (Air) U Factor (Argon)
Clear / Clear 76% 0.70 0.35 N/A
LoĒ²-270 (#2) / Clear / LoĒ²-270 (#5) 55% 0.35 0.19 0.15
LoĒ²-272 (#2) / Clear / LoĒ²-272 (#5) 57% 0.31 0.19 0.15
LoĒ²-366 (#2) / Clear / LoĒ²-366 (#5) 47% 0.24 0.19 0.14