Glass packets
123123Glass packets
Important criteria for the evaluation of the glass packet are:
U: Coefficient of thermal transfer – thermal insulation.
G: Solar factor (indicator of the entire quantity of solar energy passing through the glass) – it is important for the air-conditioning.
TL: Light transfer (indicates the percentage quantity of light that has passed through the glass as compared to the entire amount of radiated light).
Selectivity: The high selectivity contributes to the rooms being less dependent on the atmospheric conditions. The optimum selectivity levels are ≤ 2.
What characteristics must have the building glass
The glass packet of the building can impact between 70 and 90 % the energy consumption levels. That is the reason why, it is preferable for the glazing to possess the following characteristics:
A low solar factor;
A high degree of letting the light pass through;
A high selectivity;
A low U value;
Coefficient of thermal transfer U indicates the quantity of heat that passes through 1 sq. m. of glass for 1 hour with temperature difference of 1 degree between both sides of the glass.
When considering the question of thermal protection, it is of primary importance for us to pay serious attention to the thermal losses in a building. The studies conducted by specialists have provided the following information on the heat losses:
Floors – 9 %;
Walls – 26 %;
Roof – 24 %;
Windows – 41 %;
We cannot help mentioning that about 85 % of each separate window fall to the glass in it. From here. We can formulate one of the basic problems regarding the improvement of thermal control in every home, namely, the correct selection of the glasses.
Table with coefficients for double glass packets with thickness of 24 mm.
| Type of glass packet | Level of letting the light pass through |
Solar factor | UV transfer | Thermal transfer | Noise transfer |
|---|---|---|---|---|---|
| Float + Float |
81% | 70% | 44% | 2.7 | 30dB |
| Float + “low-E” (Ar) |
80% | 64% | 42% | 1.4(1.2) | 30dB |
| Float + 4 season(Ar) |
80% | 65% | 28% | 1.4(1.2) | 30dB |
| “low-E” + “low-E”(Ar) |
78% | 57% | 42% | 1.1 | 30dB |
| Float + Laminated |
81% | 7.7% | 10.5% | 2.8 | 36dB |
| Laminated + “low-E” (Ar) |
78.1% | 62.4% | 7.4% | 1.5(1.1) | 36dB |
| Green + Float |
34% | 27% | 6.3% | 2.7 | 30dB |
| Green + “low-E”(Ar) |
33% | 23% | 4.3% | 1.4(1.1) | 30dB |
| Blue + Бяло |
24.3% | 26.4% | 6% | 2.7 | 30dB |
| Blue + “low-E”(Ar) |
23.5% | 21.6% | 4% | 1.4(1.1) | 30dB |
| Reflective + Float |
40% | 35.4% | 25.7% | 2.7 | 30dB |
| Reflective + “K”(Ar) |
39.3% | 30.8% | 15.8% | 1.4(1.1) | 30dB |
Table with coefficients for triple glass packets with thickness of 32 and 40mm.
| Type of glass packet |
Level of letting the light pass through |
Solar factor | UV transfer | Thermal transfer | Noise transfer |
|---|---|---|---|---|---|
| Float +Float + Float |
73.6% | 69.4% | 44.5% | 1.9 | 33dB |
| Float + Float + “low-E” (Ar) |
71.1% | 58.6% | 27.3% | 1.3(1.1) | 33dB |
| “low-E” +Float + “low-E” (Ar) |
68.7% | 41% | 51.3% | 0.8 | 33dB |
| “K” + Float + 4 season |
68.7% | 43% | 36% | 0.8 | 33dB |
| Laminated + Float + “low-E” (Ar) |
71.3% | 56.4% | 6.5% | 1.4(1.2) | 40dB |
