Business and Technical Concepts for Deep Energy Retrofits of Public Buildings (IEA Annex 61)

IEA Energy in Buildings and Communities Programme Annex 61 Definition of Deep Energy Retrofit (DER): Deep Energy Retrofit is a major building renovation project in which site energy use intensity, including plug loads, has been reduced by at least 50% from the pre-renovation baseline.
The objectives of Annex 61 are:
To provide a framework along with selected tools and guidelines to significantly reduce energy use (by more than 50%) in public buildings undergoing major renovation
To gather and, in some cases, research, develop, and demonstrate innovative and highly effective bundled packages of Energy Conservation Measures for selected building types and climatic conditions
To develop and demonstrate innovative, highly resource-efficient business models for retrofitting buildingsusing appropriate combinations of public and private funding
The website contains many publications and presentations on Deep Energy Retrofits.