COMMERCIAL INSULATING GLASS PERFORMANCE DATA 

GLASS TYPE/PRODUCT CODE

GLASS
THICKNESS
Inches

TRANSMITTANCE
%

REFLECTANCE
EXTERIOR

WINTER
NIGHTTIME
U-Value

SUMMER
DAYTIME
U-Value

SHADING
COEFFICIENT

RELATIVE
HEAT GAIN
Btu’s/Hr/Ft²

Daylight 

Solar 

UV 

Daylight 

Solar 

1"*

1 1/2"*

1"*

1 1/2"*

Heat Mirror™ Insulating Glass

Clear Std. IG

1/4

79

61

50.0

15

12

0.48

0.49

0.55

0.51

0.81

169

HMTC88

1/4

63

34

0.50

14

23

0.27

0.18

0.32

0.22

0.55

114

HMSC75

1/4

61

27

0.50

23

34

0.30

0.21

0.35

0.25

0.41

87

HM88

1/4

70

42

0.50

19

23

0.32

0.23

0.37

0.27

0.62

128

HM77

1/4

63

33

0.50

23

32

0.31

0.22

0.36

0.25

0.49

103

HM66

1/4

53

26

0.50

33

40

0.31

0.22

0.35

0.24

0.39

83

HM55

1/4

46

21

0.50

40

45

0.31

0.21

0.34

0.23

0.33

71

HM44

1/4

37

17

0.50

49

50

0.31

0.21

0.34

0.23

0.27

60

Green Std. IG

1/4

69

39

25.0

13

8

0.48

0.49

0.57

0.55

0.56

121

HMTC88

1/4

55

24

0.50

12

10

0.27

0.18

0.32

0.22

0.40

85

HMSC75

1/4

53

21

0.50

18

14

0.30

0.21

0.36

0.25

0.34

73

HM88

1/4

61

29

0.50

15

11

0.32

0.23

0.37

0.27

0.44

93

HM77

1/4

55

24

0.50

18

14

0.31

0.22

0.36

0.26

0.38

81

HM66

1/4

46

19

0.50

26

18

0.31

0.22

0.35

0.24

0.32

68

HM55

1/4

40

16

0.50

31

20

0.31

0.21

0.35

0.24

0.28

61

HM44

1/4

32

13

0.50

38

23

0.31

0.21

0.35

0.24

0.24

53

Azurlite Std. IG

1/4

64

29

24.0

12

7

0.48

0.49

0.57

0.56

0.46

100

HMTC88

1/4

51

20

0.50

11

8

0.27

0.18

0.32

0.21

0.34

73

HMSC75

1/4

49

19

0.50

17

10

0.30

0.21

0.36

0.25

0.31

67

HM88

1/4

56

23

0.50

14

9

0.32

0.23

0.37

0.27

0.37

79

HM77

1/4

51

20

0.50

17

10

0.31

0.22

0.36

0.26

0.33

71

HM66

1/4

43

16

0.50

23

13

0.31

0.22

0.35

0.24

0.28

62

HM55

1/4

37

14

0.50

28

15

0.31

0.21

0.35

0.24

0.25

56

HM44

1/4

30

11

0.50

34

17

0.31

0.21

0.35

0.24

0.22

49

Bronze Std. IG

1/4

48

39

21.0

9

8

0.48

0.49

0.57

0.55

0.58

124

HMTC88

1/4

38

21

0.50

8

13

0.27

0.18

0.32

0.22

0.38

80

HMSC75

1/4

36

17

0.50

11

18

0.30

0.21

0.36

0.25

0.30

64

HM88

1/4

42

27

0.50

10

13

0.32

0.23

0.37

0.27

0.43

91

HM77

1/4

38

20

0.50

11

17

0.31

0.22

0.36

0.26

0.35

75

HM66

1/4

32

16

0.50

15

21

0.31

0.22

0.35

0.24

0.28

62

HM55

1/4

27

13

0.50

18

22

0.31

0.21

0.35

0.24

0.25

55

HM44

1/4

22

10

0.50

21

24

0.31

0.21

0.35

0.24

0.21

48

Gray Std. IG

1/4

40

33

20.0

7

7

0.48

0.49

0.57

0.56

0.52

112

HMTC88

1/4

32

18

0.50

7

11

0.27

0.18

0.32

0.22

0.34

72

HMSC75

1/4

30

14

0.50

9

14

0.30

0.21

0.36

0.25

0.27

59

HM88

1/4

35

23

0.50

8

11

0.32

0.23

0.37

0.27

0.38

82

HM77

1/4

32

17

0.50

9

14

0.31

0.22

0.36

0.26

0.31

68

HM66

1/4

27

13

0.50

12

16

0.31

0.22

0.35

0.24

0.26

57

HM55

1/4

23

11

0.50

14

17

0.31

0.21

0.35

0.24

0.23

51

HM44

1/4

19

9

0.50

16

19

0.31

0.21

0.35

0.24

0.20

45

California Series® Insulating Glass¹

Std. Laminated IG

1/4

81

57

0.50

16

12

0.48

N/A

0.55

N/A

0.77

161

White Water Crystal²

1/4

65

32

0.50

13

32

0.48

N/A

0.54

N/A

0.45

98

Sea Foam Clear

1/4

63

29

0.50

12

26

0.48

N/A

0.55

N/A

0.42

93

Sierra Green

1/4

58

24

0.50

11

25

0.48

N/A

0.55

N/A

0.37

83

Moss Green³

1/4

54

22

0.50

10

25

0.48

N/A

0.56

N/A

0.35

77

Tahoe Blue

1/4

54

22

0.50

10

25

0.48

N/A

0.56

N/A

0.35

77

Mojave Bronze

1/4

46

21

0.50

9

25

0.48

N/A

0.56

N/A

0.35

77

Carmel Gray

1/4

42

20

0.50

8

13

0.48

N/A

0.56

N/A

0.33

74

*Overall unit thickness.
Performance information for LOF EverGreen® and Ford’s Blue is available from Southwall. Data used for Green, Blue, Bronze and Gray is that for PPG Industries Solex®, Azurlite®, Solarbronze® and Solargray®. All data calculated using 1995 Spectral Data from Lawrence Berkeley Laboratories’ Window 4.1 analysis program. For metric values, contact Southwall’s Architectural Services Department at 1-800-365-8794.
1 Uses 1/4" California Series used as outside lite of insulating glass unit with 1/4" clear inside lite.
2 Uses PPG Starfire® low-iron glass.
3 Uses LOF EverGreen