Combined (multipurpose) IGU

The insulating glass units functionallity stands in close proximity with the functionallity of the glazed area of the building. In this respect they need to provide the following:

  • Low U coefficient and low heat loss during the winter.
  • As high sun erergy (measured with SF) transmission as possible, which allows the accumulation of the little available heat in the winter.
  • High light tarnsmission in order to keep the rooms naturally illuminated.
  • Neurtral color.
  • Reliable sun protection in the summer and low air-conditioning costs.
Achieving all of the above sometimes requires compromises. Bulit Glass Ltd. offers the following combinations for best energy saving and solar protection:
  • Colored glass (outside, solar protection) + Low-E glass with soft coating (inside, energy saving)
  • Glass with colored or transparent solar protection layer (outside, solar protection) + Low-E with soft coating (inside, energy saving)
  • Universal glass of type "Energy", "Sunergy" or "Stopray" (outside) + float flass (inside)
Structure Light
prop.
Energy
prop.
U val. Noise
reduct.
[%] [%] [W/m2.K] Rw Noise
LT LR UVТ EA ЕR SF Air Argon dB suppr. [%]
4 colored* - 16 - 4 Low-E 68 12 10 45 10 45 1.3 1.1 29 15
5 colored* - 16 - 4 Low-E 64 10 7 59 7 40 1.3 1.1 30 20
4 Blue /Azur - 16 - 4 Low-E 55 10 12 46 10 45 1.3 1.1 29 15
5 Blue /Azur/ - 16 - 4 Low-E 50 8 10 60 9 38 1.3 1.1 30 20
4 stopsol clear - 16 - 4 Low-E 56 37 14 18 40 48 1.3 1.1 29 15
4 stopsol classic* - 16 - 4 Low-E 27 35 2 56 29 20 1.3 1.1 29 15
4 Sunergy - 16 - 4 float 61 12 31 42 12 52 2 1.8 29 15
4 Energy - 16 - 4 float 71 12 7 30 31 42 1.3 1.1 29 15
  * - applies to green colored glass

Advantages:

  • Low solar factor (SF), therfore a good solar protection during the summer season. Avoidance of the greenhouse effect, and lower air-conditioning costs.
  • Low coefficient of heat transmission U and low heating costs during the cold season

Disadvantages:

  • Due to the relatively low LT and SF properties - reduced light and heat transmission during the winter period. This negative effect is reduced with the use of green float glass or glass of type "Energy" as the outer glass of the IGU.
  • Due to high enrgy absorbtion (ÅÀ) – relatively low thermal resistance, which in rare cases might bring the need for its tempering .
  • Relatively higher price.