What are U values?

Windows are often seen as the weak point of a house. But even here there are big differences. By enclosing air chambers, the insulating capacity of a building material is increased. These serve as a heat buffer, so to speak. This inclusion happens, for example, with multi-glazed windows. A double or triple-glazed window has air buffers between the individual panes, which considerably reduce the heat transfer coefficient. A single-glazed window, for example, has a U-value of approximately 5.3 W/m2K, whereas a double-glazed window only has a U-value of 1.3 W/m2K. With a triple-glazed window, values of up to 0.8 W/m2K and less can even be achieved. In general, the U-value of windows depends on the frame material, the glazing and the tightness. The U-value of windows can be divided into three different heat transfer coefficients.

Heat transfer coefficient of the window frame only.
Uf = U frame – the U value of the window frame.
The Uf value is determined for the frame-sash combination.

Heat transfer coefficients of the glazing only.
Ug = U glazing – the U value of the glazing.
It depends on the number of panes, the distance between the panes and the type of glass filling of the space between the panes.

Heat transfer coefficient for one panel (filling) only.

Heat transfer coefficients of the window component including glazing are usually calculated according to DIN 10077-1.
Uw = U window – the U value of the entire window It includes the values for the window frame and the glazing.
A low U-value for windows and doors is particularly important because it allows energy costs to be saved. If you pay attention to the different insulation values of materials and their optimum composition when you buy them, you can save yourself the annoying extra costs for heating later on.

Heat transfer coefficients of the front door component including glazing etc.

Heat transfer coefficients of the curtain wall component.

Welcome to ENERsign® Price Configurator with U-Value window Calculation:

You don’t want to go through the trouble of obtaining various offers, but would like to find out the recommended prices and U-values for our high-quality ENERsign®primus window? Then try our price configurator, here you can put together your desired windows as you wish and try out different sizes and designs.

All you need is the desired dimensions and window types and you can configure immediately. The window price and U-value window will be adjusted automatically, so that you always have an overview and can compare directly.

We are uncompromising in the product we offer:
ENERsign®primus elements with at least triple glazing with a U-value glass of 0.52 W/m²K and a g-value of 53%. Other designs and special glasses are available on request.

Welcome to the ENERsign® U-Value window configurator:

The U-value window is also called heat transfer coefficient and according to the standard DIN EN 10077 it indicates the amount of thermal energy lost through a window to the outside.

The U-value window is calculated using the formula W/(m²K), i.e. watts per square metre and Kelvin. This value refers to the entire window and defines the amount of energy per unit of time that flows through an area of one square meter when the air temperature on both sides differs by one Kelvin. The lower this value is, the less energy or heat the window emits.

Add a product
Add a product
Add a product
Add a product

Configure window

Gesamtpreis (inkl. 19% MwSt)
0€ - 0
Potentially avoided CO2 emissions over 30 years :
Potentially saved energy and CO2 costs over 30 years:
Export to Excel
0 (W/m2K)
Please add a product to configure it.