IEA EBC Annex 94 – Validation and Verification of In-situ Building Energy Performance Measurement Techniques

This project is the Austrian contribution to the international IEA EBC Annex 94. It advances and standardises in situ measurement methods to capture real building energy performance, with a focus on the heat transfer coefficient, HTC, as a key indicator of thermal losses. AEE INTEC and TU Wien contribute methodological expertise, research infrastructure and results from ongoing projects to the international work while ensuring a direct benefit for national strategies, standardisation and renovation programmes.

Annex 94 follows an interdisciplinary approach across five subtasks and links practical needs such as retrofit decisions, funding logic and quality assurance to methodological progress. This includes uncertainty analysis, validation, performance diagnostics and open data use. In this way the project addresses the performance gap between calculated design values and actual energy use. Applying improved methods to different building types, climate zones and use patterns creates a robust evidence base for retrofit pathways, funding policy and decarbonisation strategies. The results also support quality assurance in the existing building stock and help assess retrofit measures in a realistic way. There are further synergies with other IEA activities such as Energy Storage Task 43 led by AEE INTEC.

In line with Austria’s NEKP, the BMIMI research and innovation priorities and European initiatives such as the EPBD, the project strengthens reliable assessment methods for existing buildings. Targeted dissemination and communication make the outcomes accessible to policy makers, planners, technology providers, funding bodies and education. Austria is thereby positioned internationally as a methodological driver for standardised, valid and practice oriented building performance measurement.