This International Standard provides the method of calculation of the thermal resistance and thermal
transmittance of building components and building elements, excluding doors, windows and other glazed units,
curtain walling, components which involve heat transfer to the ground, and components through which air is
designed to permeate.
The calculation method is based on the appropriate design thermal conductivities or design thermal
resistances of the materials and products for the application concerned.
The method applies to components and elements consisting of thermally homogeneous layers (which can
include air layers).
This International Standard also provides an approximate method that can be used for elements containing
inhomogeneous layers, including the effect of metal fasteners, by means of a correction term given in
Annex D. Other cases where insulation is bridged by metal are outside the scope of this International
Standard.
ISO 6946:2007 Referenced Document
ISO 10456 Building materials and products - Hygrothermal properties - Tabulated design values and procedures for determining declared and design thermal values; Technical Corrigendum 1*, 2009-12-01 Update
ISO 13789 Thermal performance of buildings - Transmission and ventilation heat transfer coefficients - Calculation method*, 2017-06-01 Update
ISO 7345 Thermal performance of buildings and building components — Physical quantities and definitions*, 2018-03-08 Update
ISO 6946:2007 history
2017ISO 6946:2017 Building components and building elements - Thermal resistance and thermal transmittance - Calculation methods
2007ISO 6946:2007 Building components and building elements - Thermal resistance and thermal transmittance - Calculation method
2003ISO 6946:1996/Amd 1:2003 Building components and building elements - Thermal resistance and thermal transmittance - Calculation method; Amendment 1
1996ISO 6946:1996 Building components and building elements - Thermal resistance and thermal transmittance - Calculation method