ISO 13787:2003 establishes a procedure for the determination and verification of declared thermal conductivity, as a function of temperature, of thermal insulating materials and products used for the insulation of building equipment and industrial installations.

Informative annex B gives an optional method for establishing the thermal conductivity curve or table from measured values.

ISO 13787:2003 is not applicable to thermal insulating products used in building envelopes. For the procedures which are used for these products, see ISO 10456, "Building materials and products - Procedures for determining declared and design thermal values".