You are now: Home »
What exactly do the U and g value mean?
What exactly do the U and g value mean?
Technical parameters
The basic quality required of insulating glass is the presence of increased thermal insulation, i.e. the greatest reduction of heat loss.
U value
- The basic measure unit for establishing the heat loss of a construction segment
- The value indicates the amount of heat that passes through one m2 of a construction segment in a time unit during a temperature differential between indoor and outdoor air of 1 degree Kelvin
- The measurement unit is W/m2K
- The lower this value is the better the thermal insulation of the construction material
- A low U value is the most important characteristic of insulating glass
- Low heat loss from better thermal insulation leads to higher surface temperature of the interior windowpane and thus higher comfort in the room
- Enables the use of less heating equipment and as such offers both economic and ecological advantages
G value
- The coefficient of the permeability of total solar radiation energy stated as %
- Composed of the direct transmission of energy and the secondary dispensation of heat of the glazed surface toward the interior, which occurs on the basis of absorbed solar rays.
- The sun can heat a room only by glass and thus also contribute to heating without any additional expenses
- What is welcomed in winter can be unpleasant in summer, because gaining energy through solar radiation means heat
- The correct course is high thermal insulation, which means a low U value combined with a G value that is not too high
- The technological standard has become insulating glass with a plated layer
- Formed by at least two panes of glass, one of which is coated with an extremely thin layer of high-grade metal, which radically reduces thermal losses