P 1098 – Building Redevelopment – Solutions for Roof and Façade Systems using Lightweight Steel Constructions




P 1098 – Building Redevelopment – Solutions for Roof and Façade Systems using Lightweight Steel Constructions

Energy related refurbishments and building in existing structures gain in the framework of climate protection policy in importance. Various studies show that a significant reduction of emissions and energy consumption in the building sector can only be achieved by the refurbishment of existing buildings. Particularly upon industrial and commercial buildings, the thermal and energetic quality of the building envelope realized in the past often no longer meet the current and future requirements.
In this research project the approach to carry out the energetic refurbishment during operation (without cost-intensive downtime) is pursued. In order to improve the thermal quality of the existing façade, additional heat-insulating components should be installed on the outside. Particularly promising is the use of building systems in lightweight steel or metal construction.
Sandwich panels with double-sided steel face layers and polyurethane or mineral wool insulation core provide a highly effective option in this context. They not only have very good thermal properties but can also be installed very quickly and economically. In addition, so-called modular lightweight steel build-up systems offer a further alternative to energetically reinforce existing building envelopes. Priority will be given to existing buildings whose roofs and façades have already been conducted in lightweight steel construction, with a focus on steel liner tray façades. In addition, existing roofs and façades in solid construction are considered with regard to a possible lightweight steel construction renovation.
From a building physics point of view, not only the aspects of thermal insulation are examined, but also questions arising from the change in the moisture-technical behavior of the rehabilitated component.
Also structural design boundary conditions must be considered among energetically refurbishments. Existing building components that are affected by the refurbishment need a renewed static poof based upon present technical rules and the assumptions for wind- and snow loads were subject to significant changes in recent decades. After a systematic record of the normative development in this sector, possible means for the static proof of the refurbished components concerning the additional lightweight steel construction systems and the changed load assumptions will be investigated.
The aim of the research project is to develop rules and structural design approaches that allow statements on the energetic quality achievable with the renovation and their effects in the moisture-related component behavior. On the other hand, possibilities are developed that capture the structural aspects resulting from the combination of the existing static proof of the existing construction and the current load assumptions in connection with the consideration of the remediation measure.

Published in:
January 2021

Univ.-Prof. Dr.-Ing. M. Kuhnhenne, Dipl.-Ing. M. Brieden, Univ.-Prof. Dr.-Ing. D. Ungermann, Dipl.-Ing. A. Wiegand