This Technical Specification describes the basic principles to be followed in the development of standards intended to support the assessment of the energy performance of buildings using a holistic approach. The main goal is to obtain a set of EPB-standards that are a systematic, clear and comprehensive package for the benefit of professionals and government entities. This Technical Specification gives general, qualitative guidance on the required quality, accuracy, usability and consistency of EPB-standards in order to provide a balance between: - the accuracy and level of detail, and; - the simplicity and availability of input data. Hidden complexities are also taken into account, such as the impact of differences in the overall legal frameworks on the national choices and national input data. The basic principles are the basis for detailed technical rules and for a common overarching structure for the set of EPB-standards. The basic principles for EPB-standards cover the following aspects; - the standardization process, including collaborations and consultations; - the application range of the standards; - common general organization of each standard and the national implementation; - the overarching structure for the energy performance assessment; - common model(s) and editorial rules for each standard; - common quality aspects for each standard.