Roughly 75% of the buildings in Germany were built before the first ordinance on thermal insulation took effect. To make this huge number of properties more energy-efficient, housing companies, municipalities, and other property owners need a reliable basis for decision-making. In a joint project with partners from academia and industry, researchers at the Karlsruhe Institute of Technology (KIT) have now developed a digital platform featuring AI-based applications that can analyze complex data of buildings within a few minutes and present proposals for renovation options.
Energy upgrades are considered key to a climate-friendly transformation of the building sector. However, the preparation of such upgrade measures is often a very tedious task: Information is available in different formats, has to be consolidated manually and assessed based on technical, economical, and ecological criteria.
This is exactly where NaiS (short for Sustainable smart renovation measures”) comes in. The platform pools digital services that autonomously correlate and evaluate data from images, floor plans, text documents, and static building information sources. Using artificial intelligence (AI), the system makes up for missing information, structures and contextualizes data for digital building models, and visualizes the results as 3D models. “With NaiS, we’re establishing a data-based foundation that enables significantly faster and more transparent decisions on energy upgrades. For large building stocks in particular, this is a crucial step towards a sustainable transformation,” said co-project leader Philipp Zielke from KIT’s Institute of Technology and Management in Construction (TMB).
“The sustainable development of our building stock is the main challenge the construction and real-estate industries will have to face in the future,” says Dr. Karoline Fath, Head of the division for sustainable construction at Ed. Züblin AG, a project partner from industry. “We believe that AI technologies such as the building stock assessment services implemented in NaiS can make a major contribution here – for the benefit of our planet and society.”
Analyses Take Only Minutes instead of Days
The project included four testing sessions involving 104 potential users. The feedback was mostly positive: 93% of the participants confirmed that the platform clearly offered added value, 87% benefited from specific support in the assessment of buildings, and just as many would recommend NaiS to other users.
The platform clearly outpaced manual processing: Tasks previously requiring about 16 working hours were completed by NaiS within 10-20 minutes. Large institutional property owners and municipalities in particular will benefit from such a 50-fold acceleration of the decision-making processes and significantly reduced research efforts.
Results Will Be Used in Practice and Follow-Up Research
The team plans to use and refine the approaches and instruments developed as part of the project beyond its term. The platform is now available from the German Sustainable Building Council (DGNB). In addition, follow-up projects tie in with the NaiS results, for example the joint ConCIRCLE project, which is funded with EUR 1.8 million by the Federal Ministry of Research, Technology and Space. KIT will be the consortium leader in this project again.
The aim of the ConCIRCLE project is to design a digital system for assessing the recyclability of reinforced concrete components. To this end, the researchers will enhance the AI technologies developed in NaiS and combine them with ecological and economic assessment methods.
Presentation of Project Results at the NaiS Summit
On June 11, 2026, the “NaiS Summit” will be held as the closing event of the NaiS project. Representatives from science, construction industry, government, and administration will discuss approaches for the digital and sustainable transformation of the building stock and the potentials offered by AI-based energy upgrade planning.
NaiS started in May 2023 and was funded with EUR 4.1 million by the Federal Ministry of Research, Technology and Space. KIT members of the consortium are the TMB, the Institute for Automation and Applied Informatics, and the Karlsruhe Service Research Institute. External partners are Ed. Züblin AG, Concular GmbH, CAALA GmbH, and the German Sustainable Building Council.
More information on the NaiS project (in German only)
More information on the ConCIRCLE project (in German only)
In close partnership with society, KIT develops solutions for urgent challenges – from climate change, energy transition and sustainable use of natural resources to artificial intelligence, sovereignty and an aging population. As The University in the Helmholtz Association, KIT unites scientific excellence from insight to application-driven research under one roof – and is thus in a unique position to drive this transformation. As a University of Excellence, KIT offers its more than 10,000 employees and 22,800 students outstanding opportunities to shape a sustainable and resilient future. KIT – Science for Impact.