Draft EN ISO 14683: Thermal bridges in building construction
This International Standard deals with simplified methods for determining heat flows through linear thermal bridges which occur at junctions of building elements. It specifies requirements relating to thermal bridge catalogues and manual calculation methods.
Objectives of the consultation
This International Standard is part of a series of standards aiming at international harmonisation of the methodology for the assessment of the energy performance of buildings, called "EPB set of standards". The standard provides the means (in part) to assess the contribution that building products and services make to energy conservation and to the overall energy performance of buildings. Thermal bridges in building constructions give rise to changes in heat flow rates and surface temperatures compared with those of the unbridged structure. These heat flow rates and temperatures can be precisely determined by numerical calculation in accordance with ISO 10211. However, for linear thermal bridges, it is often convenient to use simplified methods or tabulated values to obtain an estimate of their linear thermal transmittance.
The effect of repeating thermal bridges which are part of an otherwise uniform building element, such as wall ties penetrating a thermal insulation layer or mortar joints in lightweight blockwork, needs to be included in the calculation of the thermal transmittance of the building element concerned, in accordance with ISO 6946.
Although not covered by this International Standard, thermal bridges can also give rise to low internal surface temperatures, with an associated risk of surface condensation or mould growth.
To download the draft standard, please follow the link below.
CIBSE did not submit a response to this consultation as there were no significant comments from CIBSE Members.