What does the heat transfer coefficient say?

Heat transfer coefficient = U-value (formerly k-value): central unit of measurement when determining the heat loss of a building component. It indicates the amount of heat that passes through 1 m² per unit of time at a temperature difference of 1 Kelvin between the adjacent room and outside air. The smaller the U-value, the greater the thermal insulation. The unit of measurement is W/(m²K).

The heat transfer coefficient, also called the U-value, describes the insulation properties of a building component. The lower the coefficient, the better the thermal insulation.

The so-called heat transfer coefficient, also called U-value (U = unit of heat transfer) or thermal insulation value, is used to calculate the heat loss of a house. As soon as there is a difference in temperature between two sides of a building element, a heat exchange takes place. The U-value indicates the heat transfer through a layer of material (e.g. a window or a wall) from one fluid (e.g. a gas or a liquid) into a second fluid. Simplified: The U-value is a measure of how much heat is released to the outside through a building component and thus provides information about the thermal insulation of a window. Strictly speaking, it measures the amount of energy per area that flows through a solid body. The smaller the value, the better the insulation and the lower the heat loss. The U-value is particularly low, for example, with building materials such as softwoods (0.13 W/m2K), hardwoods (0.18 W/m2K) or bricks (0.23 W/m2K) – these materials are therefore well suited for thermal insulation. In contrast, materials such as acrylic glass (5.3 W/m2K) or iron (60 W/m2K) have a high U-value. The unit of the thermal insulation value W/m2K means “Watt per square metre and Kelvin”.

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.

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Gesamtpreis (inkl. 19% MwSt)
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Potentially avoided CO2 emissions over 30 years :
Potentially saved energy and CO2 costs over 30 years:
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0 (W/m2K)
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