Цитата с сайта CWCT http://www.cwct.co.uk/specification/home.htm
Specifications for building envelopes may be wholly bespoke or follow one of the recognised building envelope specifications. However, all specifications have to be customised to take account of the external climate and the building use.
The CWCT ‘Standard for systemised building envelopes’ gives a framework for specifying building envelopes and provides a ‘Specifiers checklist’ showing information that will change from project to project.
Т.е. речь идет о составлении технических условий/требований