The KENAK (Greek Regulation on the Energy Performance of Buildings) and the related TOTEE technical guidelines constitute the institutional and technical framework for determining the energy performance of buildings in Greece. They define the parameters and technical characteristics of the building envelope and of the technical systems that produce, manage and consume energy, as well as the methodology for assessing their energy efficiency.

At European level, the Energy Performance of Buildings Directive (EPBD) sets the framework for improving energy performance, decarbonizing the building stock and transitioning towards nearly Zero Energy Buildings (nZEB). In parallel, the European Directives on Energy Labelling and Ecodesign regulate the energy performance of appliances and technical systems used in buildings.

The Smart Readiness Indicator (SRI) methodology evaluates the degree of smart readiness of a building by examining the technological maturity and automation level of its installations. It includes domains both within and beyond the traditional scope of KENAK, such as the installation of electric vehicle charging stations and the interaction of the building with the electricity grid. At the same time, it indirectly assesses energy efficiency through the intelligent operation and optimization of building systems.

The IsZEB Standard integrates into its assessment methodology the requirements and criteria derived from the aforementioned European and national directives, creating a comprehensive and optimized framework for evaluating both the energy performance and the smart readiness of a building.

It also covers and categorizes all major primary energy consumers in the following sectors:

• Passive Design
• Heating
• Cooling
• Mechanical Ventilation
• Domestic Hot Water (DHW)
• Lighting Systems
• Electrical Equipment
• Contribution of Renewable Energy Sources (RES)

Additionally, it includes:

• Comprehensive assessment of Building Smart Readiness
• Integration of assessment levels aligned with national energy transition strategies and European harmonization directives
• Specific assessment levels within the IsZEB methodology covering critical building parameters, such as:
  • Passive Design
  • Moisture Management
  • Thermal Inertia
  • Waste Collection and Management
• Distinct yet interrelated assessment axes, which are incorporated into the overall building rating
• Optimization of energy performance, functionality and environmental performance of the building
• A modern and multi-level assessment tool combining regulatory compliance, energy efficiency and digital smart readiness
• Support for the transition to sustainable, smart and climate-neutral buildings