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Energy Saving IGU

To achieve an energy saving effect one must reduce the heat transmission through the material. This can be done by:

Changing the air space between the two glass sheets in the IGU.
use inertial gas (argon, crypton, etc.)
Use of Low-E glass with soft and hard coating.

Due to the good properties of the Low-E glass, the latter has proven to be most effective on the european market, because it achieves lowest coefficient of heat transmission U, which plays the biggest role when it comes to energy saving.

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 float - 16 - 4 Low-E soft coating	79	13	21	19	25	64	1.3	1.1	29	15
4 float - 16 - 4 Low-E hard coating (KA)	72	16	35	16	16	72	1.8	1.6	29	15
5 float - 16 - 4 Low-E soft coating	78	13	21	21	24	63	1.3	1.1	30	20
5 float - 16 - 4 Low-E hard coating (KA)	74	17	33	25	16	71	1.7	1.5	30	20
6 float - 16 - 4 Low-E soft coating	78	13	20	23	23	62	1.3	1.1	31	25
6 float - 16 - 4 Low-E hard coating (KA)	73	17	32	26	16	70	1.7	1.5	31	25

Advantages:

Extremely low coefficient of heat transmission U with Low-E (low emittance) glass with soft coating, high energy saving properties and lower heating costs in the winter.
High LT (Light transmission) and SF (Solar factor) and thus enough natural light in the winter season.
Low SF (solar factor) in comparison to the conventional glazing and thus less heat transmission in the summer season. This effect is most noticable when glazing on the northen side, due to the low direct shortwave radiation.

Disadvantages:

Hi SF (solar factor) in comparison to the solar protecting glass, which leads to higher heating in the summer season and the so called greenhouse effect. That"s why we recommend glazing with combined insulating units on areas which are directly exposed to sun light.