The insulation values are not as good as in the casement systems when using a brush seal as the air inlet is higher, but they improve the values of any aluminium window.
The thermal transmittance values achieve a value of U= 1,8 W/m2K.
Despite not reaching the airtightness levels of the casement systems, the PremiLine System achieves very good sound insulation results with up to 34 dB of sound reduction.