The International Organization for Standardization is a network of national standards institutes of 157 countries. ISO has a Geneva-based secretariat to coordinate the system. Individual member organizations may suggest new standards, which are then developed by ISO technical committees, and thereafter circulated to members who vote on whether to accept the standards.
ISO has recently issued new guidelines to promote designing energy efficiency into new buildings. The standard provides energy-related requirements for designing buildings and for achieving specific energy efficiency targets. The criteria can be applied to heating, cooling, lighting, hot water, and ventilation systems. Both published and draft standards are available, for a fee, from http://www.iso.org/iso/search.htm?qt=Building+Environment+Design&searchSubmit=Search&sort=rel&type=simple&published=on.