Glass Performance Comparison Chart (effective June 30, 2004)
A
D
E
F
G
H
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M
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Q
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Description
Construction












Transmittance
(%)
Reflectivity
(%)
ASHRAE
Winter
European

Four Seasons' Standard Glass CONSERVAGLASS SELECT™

Exclusive High Performance Insulated Safety Glass
Tempered safety glass which incorporates advanced exotic coating technology with Argon gas filling and exterior glass cleaning and protection features. Ensures superior performance and life expectancy for years of comfortable, cost-effective year-round living.

7E
MC-7E / Argon / Clear
65
25
5
11
12
0.31
0.27
65
0.25
4.0
1.13
204
78
MC-16 / Argon / Clear
16
10
7
11
25
0.18
0.15
39
0.25
4.0
1.20
123
78L
MC-16 / Argon / Laminated
15
9
1
11
24
0.17
0.15
38
0.24
4.2
1.21
120
9E
MC-7E / Argon / Clear / Argon / MC-79
57
21
2
14
17
0.29
0.25
61
0.20
5.0
1.19
199
9K
MC-7E / Krypton / Clear / Krypton / MC-79
57
21
2
14
17
0.29
0.25
59
0.14
7.1
0.80
191
97A
MC-16 / Argon / Clear / Argon / MC-72
13
6
2
11
19
0.15
0.13
33
0.20
5.0
1.16
119
97K
MC-16 / Krypton / Clear / Krypton / MC-72
13
6
2
11
19
0.14
0.12
29
0.13
7.7
0.76
102

Four Seasons' High Performance Single Glazing -- Sun Smart™
Four Seasons Seasonal Sunroom, our Series 200, uses a high performance single-glazed product under the trademark Sun Smart™ to improve the performance and effectively extend the seasonal use of your seasonal sunroom.
 
7
Green Single Glazing
83
60
43
8
8
0.81
0.70
158
0.96
1.04
5.91
 

The Competition's Standard Glass Single Glazing
Can only be used in unconditioned rooms designed for "part-time" use!
1
Clear Single Glazing
90
83
73
9
9
0.99
0.85
213
1.10
0.9
5.60
672
2
Bronze Single Glazing
67
64
39
7
7
0.84
0.72
183
1.10
0.9
5.60
577
4
Azurlite Single Glazing (Blue)
77
43
36
8
8
0.67
0.57
149
1.10
0.9
5.60
469
7
Green Single Glazing
76
48
28
7
8
0.71
0.61
158
1.10
0.9
5.60
498

The Competition's Standard Glass Double Glazing
Does not allow for comfortable, cost-effective year-round living.
Better than Single Glazing but still not energy efficient.
20
Clear / Clear
81
69
58
16
16
0.88
0.75
183
0.49
2.0
2.60
576
21
Bronze / Clear
61
54
33
11
14
0.72
0.62
151
0.49
2.0
2.60
475
23
Azurlite / Clear (Blue)
70
37
31
13
15
0.54
0.46
115
0.49
2.0
2.60
361

The Competition's Optional Glass High-Performance Double Glazing
Offers comfortable year-round living but at a significant price increase and an extended lead time.
30
Solar Cool Bronze / SG500
22
23
8
37
24
0.38
0.32
81
0.35
2.8
1.90
254
 
Solar Cool Bronze / Argon / SB60VT
21
11
3
37
17
0.23
0.20
52
0.34
2.9
1.80
165
 
Solar Bronze / HM-44 / Clear
28
14
0
30
14
0.24
0.21
53
0.31
3.2
1.70
167
 
LoE2 / Argon / Clear
72
38
16
11
12
0.47
0.41
97
0.26
3.85
1.40
309

NOTES BY COLUMN:
(C.) CODE 7E - can be used for roof in cold climates.
(E.) VISIBLE LIGHT (Glare) - The lower the better. A measure of that portion of total solar radiation visible to the human eye. Note: the glare caused by too much light can cause discomfort. Codes 74 and 78 have excellent glare control.
(G.) UV (Ultraviolet) - The lower the better. Accounts for about 50% of fabric fading. Eliminating all UV reduces fading by 50%.
(H. & I.) REFLECTIVITY - Choose a low number in the vertical area for best clarity and lowest reflectivity.
(L.) SHADING COEFFICIENT - The lower the better. Ratio of solar gain to 1/8" clear glass.
(M.) SOLAR HEAT GAIN COEFFICIENT - The lower the better. Ratio of total solar heat energy transmitted and absorbed by each layer of a glazing system.
(N.) RELATIVE HEAT GAIN - The lower the better. Amount of BTU's gained per hour per square foot of glass.
(O.) U-VALUE - BTU/HR/SQ. FT./oF The lower the better (R=1/U).
(P.) R-VALUE - The higher the better.
(Q. & R.) EUROPEAN RATINGS - Similar to US (O & P) European Environmental Conditions are Winter Temp Out=32F, Temp In=68F, Wind=7.8 mph, Direct solar=0, T Sky=32F, Summer, Temp Out=89F, Temp In=68F, Wind=7.8 mph, Direct Solar=248.2 Btu/h ft. sq, T Sky=89F.
Source: LAWRENCE BERKELY LAB
Windows 4.1 ALL values are center of glass for vertical glass. Calculations based on 90% gas fill rate. All values are based on 1/8" lites of glass with 5/8" airspace (7/8" overall).

CONSERVAGLASS SELECTTM is a registered trademark of Four Seasons Solar Products LLC.

The use of breather tubes for higher altitudes may negatively impact the performance value documented in this chart.