BS EN 674-2011 建筑玻璃.热传递系数(U值)的测定.保护热板法

标准号：BS EN 674-2011
中文标准名称：建筑玻璃.热传递系数(U值)的测定.保护热板法
英文标准名称：Glass in building. Determination of thermal transmittance (U value). Guarded hot plate method
标准类型：Q33
发布日期：2011/7/31 12:00:00
实施日期：2011/7/31 12:00:00
中国标准分类号：Q33
国际标准分类号：81.040.20
引用标准：EN 12898;ISO 8302-1991
适用范围：This European Standard specifies a measurement method to determine the thermal transmittance of glazingwith flat and parallel surfaces. Structured surfaces, e.g. patterned glass, can be considered to be flat.This European Standard applies to multiple glazing with outer panes which are not transparent to far infraredradiation, which is the case for soda lime silicate glass products, borosilicate glass and glass ceramics.Internal elements may be far infrared transparent.The procedure specified in this European Standard determines the U value1) (thermal transmittance) in thecentral area of glazing. The edge effects, due to the thermal bridge through the spacer of an insulating glassunit or through the window frame are not included. Furthermore energy transfer due to solar radiation is nottaken into account.The procedure specified in this European Standard should generally only be considered when the calculationmethod detailed in EN 673 is inappropriate or unsuitable.The document for the calculation of the overall U value of windows, doors and shutters (see [3]) givesnormative reference to the U value evaluated for the glazing components according to this standard.A vertical position of the glazing is specified.U values evaluated according to the present standard are used for product comparison as well as for otherpurposes, in particular for predicting: heat loss through glazing; conduction heat gains in summer; condensation on glazing surfaces; the effects of the absorbed solar radiation in determining the solar factor (see [1]).Reference should be made to [4], [5], or other European Standards dealing with heat loss calculations for theapplication of glazing U values determined by this standard.The determination of the thermal transmittance is performed for conditions which correspond to the averagesituation for glazing in practice.