What Are U-Values?

And why are they so important?

U-value measures the rate of non-solar heat loss or gain through a material (or assembly) due to the differences in temperature or environmental conditions between the inside and outside of the window.

U-value is expressed in terms of Watts per m2 per degree Kelvin (W/m2K) and generally falls between 2.0 and 10.0 W/m2K for Australian products. The u-value for a window takes into account the various u-values of the components making up the window.

A lower u-value indicates a window’s greater resistance to heat flow and a better insulating performance. Regardless of which climate zone (heating, cooling or mixed) the building is built in, it is always best to select window systems with a low u-value.


                                                                   The lower the number, the higher the performance.

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Thermeco window systems have some of the lowest u-values on the market. Not only does this decrease costs on cooling and heating devices within the home, more importantly it increases the sustainability of the home by reducing greenhouse gas emissions therefore helping the environment.


Click HERE to view the WERS ratings of our Thermeco Aluminium Windows Residential Range and Commercial Range

U Value