This European Standard specifies a measurement procedure to determine the thermal transmittance of glazing with flat and parallel surfaces. For the purpose of this Standard, structured surfaces may be considered to be flat.This European Standard applies to multiple glazing with outer panes which are not transparent to far infrared radiation (in the wavelength range 5μm to 50μm), which is the case for soda lime silicate glass products, borosilicate glass and glass ceramics. Internal elements can be far infrared transparent. The procedure specified inThis European Standard determines the U value (thermal transmittance) in the central area of glazing. The edge effects due to the thermal bridge through the spacer of an insulating glass unit or through the window frame are not included. Energy transfer due to solar radiation is also excluded. The procedure specified inThis European Standard should be considered only when the thermal transmittance of the glazing cannot be calculated in accordance with EN 673. The determination of the thermal transmittance is performed for conditions which correspond to the average situation for glazing in practice. NOTE Patterned glass is an example of a glass with a structured surface;
EN 675:2011 Referenced Document
EN 12898 Glass in building - Determination of the emissivity*， 2019-03-01 Update
EN 673 Glass in building - Determination of thermal transmittance (U value) - Calculation method
ISO 8301 Thermal insulation — Determination of steady-state thermal resistance and related properties — Heat flow meter apparatus AMENDMENT 1
ISO 8302 Thermal insulation; determination of steady-state thermal resistance and related properties; guarded hot plate apparatus
EN 675:2011 history
2011EN 675:2011 Glass in building - Determination of thermal transmittance (U value) - Heat flow meter method
1997EN 675:1997 Glass in Building - Determination of Thermal Transmittance (U Value) - Heat Flow Meter Method