The building sector is considered a major driver of energy-related greenhouse gas emissions, with the operation of inefficient existing buildings being a significant contributor. The research project UMiSeSa addresses this issue by developing serial renovation concepts for reinforced concrete frame structures built between the 1960s and 1980s. [1]

A transdisciplinary team of research institutes and industry partners conducted an extensive analysis of an existing sample building on KIT's South Campus. Data was collected regarding architecture, hazardous materials, load-bearing structures, thermal building envelopes, urban mining potential, and renovation concepts. Based on these findings, a holistically designed facade mockup is being developed to demonstrate construction, assembly processes, and impacts on the indoor climate, while preserving the architectural identity. The 1:1 scale mockup will be installed directly on the existing building at the KIT campus.

The insights gained will be integrated into variant studies to develop concepts for the serial renovation of comparable reinforced concrete frame structures. The project commenced in November 2025.

Contribution by Design of Structures

Within the research team, Design of Structures is responsible for analyzing the existing load-bearing framework. The objective is to design a renovation concept that utilizes sustainable materials to create a comfortable indoor climate while ensuring efficient implementation within the existing structure.

This requires introducing new loads into a structural framework that was designed based on a historical safety concept. Consequently, its results cannot be easily compared with today's safety standards under the Eurocodes. Furthermore, year-of-construction-specific standards and products for concrete and reinforcing steel additionally complicate the verification process. Structural verifications that are now performed via FEM with little extra effort were solved back then simply by adding manual reinforcement. This often makes it difficult to retrace the actual load paths. In addition, decades of usage and weathering have frequently caused structural damage that must be taken into account when introducing new loads.

These challenges of working with existing buildings often have to be resolved based on a limited data set. Site inspections, architectural drawings, structural calculations, and execution plans frequently yield incomplete or contradictory information depending on the source material. For this project, Design of Structures is developing a framework that allows a logical chain of reasoning for structural verification to be established based on the available information, while respecting grandfathering regulations.

The insights gained from the project will subsequently be presented in a guideline, enabling the transfer of these findings to the large number of comparable reinforced concrete frame structures from this construction era.

Professorship Design of Structures (dos)
Prof. Dr.-Ing. Riccardo La Magna, Josua Sickinger M.Sc., Studentische Unterstützung: Lukas Mainzer

Professorship Facility Management
Prof. Dr.-Ing. Kunibert Lennerts, Elke Widmann M.Eng.

Professorship Sustainable Construction
Prof. Dipl. Arch. Dirk E. Hebel, Fanny Kaiser Hirt M.Sc., Studentische Unterstützung: Philipp Timmermann

Professorship Building Science and Technology
Prof. Dipl.-Ing. Andreas Wagner, Seyed Hooshmand M.Sc.

Immobilienmanagement, Planen und Bauen
Friederike Hoebel, Christian Oeder

Amolsch Holzbau GmbH
Thomas Hechinger

Zimmerei Grünspecht e.G.
Markus Wolf

Zirkular GmbH
Dipl.-Ing. Architektin Kerstin Müller, Nora Meier M.Sc.

This project is funded by:

^Source:

^{[1] Deutsche Energie Agentur (Hrsg.) (dena, 2024): DENA GEBÄUDEREPORT 2025. Zahlen, Daten, Fakten zum Klimaschutz im Gebäudebestand}