Project description

The interdisciplinary project "EnWorKS", conducted by engineering, legal and economic scientists, has started in October 2013 and aims to optimize control instruments and controll procedures especially in the area of private law, so that all stakeholders involved are willing and able to implement an already technically possible increase in the energy efficiency of buildings - all of this in an environmentally and socially acceptable way. In close feedback with private and public partners and agents in the area of Kassel, innovative proposals are being developed that are technically forward-looking, economically efficient, politically enforceable, socially acceptable as well as legally practicable.

The Department of Civil Law, Corporate Law, Competition Law, lead by Prof. Dr. Martina Deckert, the Department of Building Physics, lead by Prof. Dr. Anton Maas as well as the Department of Foundations of Law, Private Law, and the Economic Analysis of Law (Law and Economics), lead by Prof. Dr. Georg von Wangenheim are working closely together to achieve all of the targets mentioned above.

Milestone 1: Analysis of deficits and existing proposals for improvement

Milestone 2: Proposal for building-related measures

Milestone 3: Proposal for complementary (non-building-related) measures



  • Rückebeil, S./Dose, M., Der Anspruch des Wohnungseigentümerers auf energetische Modernisierung, ZWE 2015, 395-400.
  • Rückebeil, S., Gesamtangemessenheitsgrenze für Unterkunft und Heizung: Notwendig, aber nicht um jeden Preis!, NZS 2015, 498-499.
  • Rückebeil, S., Gesamtangemessenheitsgrenze für Unterkunft und Heizung: Notwendig, aber nicht um jeden Preis!, NZS 2015, 498-499.
  • Höttges, K./Kirchhof, W./Klauß, S./Krüger, N./Maas, A., Leitfaden Fassadensanierung bei Nichtwohngebäuden. Fraunhofer IRB Verlag, Stuttgart 2014.
  • Klauß, S./Maas, A./Krüger, N./Joost, M., Collection, processing and use of data in existing buildings. In: Energy Efficient City Competition. Ed. H.-J. Wagner and J. Görres. Berlin: LIT Verlag, 2014, pp. 177-186.
  • Maas, A./Vaupel, K., Training manual for energy consultants. 2nd ed. Bundesanzeiger Verlag, Cologne (2014).
  • Maas, A., EnEV 2014/2016 - Auswirkung der künftigen Energieeinsparverordnung auf das Bauen im Bestand. In: Aachener Bausachverständigenage 2013 - Bauen und Beurteilen im Bestand. Ed. R. Oswald. Wiesbaden: Springer Vieweg, 2014, pp. 8-15.
  • Wagner, A./Lützkendorf, T./Voss, K./Spars, G./Maas, A./Herkel, S., Performance analysis of commercial buildings-Results and experiences from the German demonstration program 'Energy Optimized Building (EnOB)'. Energy and Buildings, 68, pp. 634-638, 2014.
  • Maas, A., Hauser, G./Höttges, K., Commentary on the EnEV. Recknagel . Sprenger . Schramek: Taschenbuch für Heizung + Klimatechnik Oldenbourg Verlag, 77th edition (2015), pp. 656-690.
  • Maas, A./Radermacher, A. (2015), Useful energy demand for heating and cooling according to DIN V 18599-2, EnEVaktuell, Heft III/2015.

Together with the Mieterbund Nordhessen e.V., a brochure entitled.

"The energy modernization of rented housing: what rights and obligations do you have as a tenant and what do you need to consider?"

was published. In connection with the energetic modernization of housing, tensions arise especially in tenancy relationships. The brochure is intended to give tenants an overview of the existing legal situation. The coexistence of energy-saving modernization, non-energy-saving modernization and maintenance measures is explained and the various legal consequences assigned. Problems arise where these measures come together in a construction process. Here, the brochure offers assistance and practical tips.

Download: The energy modernization of rented housing

  • Kossmann, B., "Failing to Protect the Tenant", presentation of results on the effect of the modernization levy at the annual conference of the European Association of Law & Economics (EALE) in Vienna on September 17, 2015.
  • v. Wangenheim, G., "Failing to Protect the Tenant," presentation of results on the effect of the modernization levy at the annual conference of the Gesellschaft für Recht und Ökonomik e.V. (GLEA) in Düsseldorf on July 24, 2015.
  • Rückebeil, S., Presentation of the project at the "Netzwerk Wärme" on April 9, 2014, Deutsche Umwelthilfe.
  • Maas, A., EnEV 2014 - What does the housing industry expect?, EBZ 2014, Bochum.
  • Maas, A., Wärmeschutz und Energieeinsparung: Typische Streitpunkte und Beurteilungsprobleme zum geschuldeten Wärmeschutzstandard, 40. Aachener Bausachverständigentage 2014, Aachen.
  • Maas, A., Energieeinsparverordnung 2014, Züblin 2014, Stuttgart.
  • Maas, A., Eckpunkte der Novellierung und wesentliche Aspekte für die Anwendung, AKTEURSFORUM Energieeinsparverordnung 2014: Energy Agency Göttingen 2014, Göttingen.
  • Maas, A., Sommerlicher Wärmeschutz, DIN Tagung: EnEV Quo Vadis - Positionen, Potenziale und Perspektiven 2014, Berlin.
  • Maas, A., Energieeinsparverordnung 2014, Züblin 2014, Stuttgart.
  • Maas, A., EnEV 2014/16: Background, practical implementation and outlook, 10th GRE Congress 2014, Kassel.
  • Maas, A., Fenstertausch als Einzelmaßnahme - Erarbeitung von Handlungsempfehlungen zur schimmelpilzfreien Teilmodernisierung von Fenstern, VFF Fachtagung Normung und Technik 2014, Frankfurt.
  • Maas, A., Rollladen + Sonnenschutz - Bedeutung für den Wärmeschutz von Gebäuden, Haupttagung des Bundesverbandes Rollladen + Sonnenschutz e.V. 2014, Palma de Mallorca.

Cluster Workshop "Buildings and Settlements

On July 17, 2014, the cluster workshop "Buildings and Settlements" took place at the University of Kassel. The workshop has enabled all projects funded by the BMBF in the series "Environmentally and socially compatible transformation of the energy system", which dealt with the energy improvements of buildings and settlements to come together in a joint meeting. With the support of the Scientific Coordination of the BMBF funding measure - WiKo SÖF Energie - an exchange of focal points, data and methods took place in order to promote cooperation.


Kick-off workshop

On April 1, 2014, a kick-off workshop was held at the University of Kassel. Numerous practitioners and scientists discussed problems and first possible solutions around the topic of building renovation. Through many field reports and a lively discussion among the workshop participants, the following main problem areas could be gathered:

1. Uncertainty about costs and benefits very high

There is a very high level of uncertainty about the costs and benefits of the possible measures for energy-efficient housing renovation. On the one hand, it is unclear which measures are efficient or useful. On the other hand, the financing options for renovation are considered complicated. The EnEV regulations are perceived as similarly complicated. Furthermore citizens seem to be skeptical about technical innovations such as smart meters.

2. Potential for conflict during implementation

When carrying out a modernization measure, various problems become apparent. Finding craftsmen is extremely difficult. In addition, the burden on residents is sometimes very great. Following a construction measure, deficiencies can occur, which in particular lead to difficulties in providing evidence and are additional factors of uncertainty. In the context of an existing tenancy, the apportionability of costs is of particular concern here. In particular, the division into non-apportionable modernization costs and apportionable modernization costs offers a high potential for conflict. The users are often unfamiliar with the use of new equipment and energy-efficient behavior in a modernized apartment. In this case, user instructions for the apartment/installations may be necessary and mandatory.

3. Neighborhood consideration is crucial

To enforce energy-efficient modernizations in residential buildings, the consideration of the entire neighborhood is crucial. The energy component is usually not the primary reason for modernization, but motivation must be built up via other areas of social coexistence. In particular, personal contact with the owners is important to reduce inhibitions and uncertainties. This can be achieved particularly well by grouping together socially connected residential areas. The domino effect can also be used most efficiently in neighborhoods. Overall, the question arises as to which actors need to be given which incentives and whether, in some constellations, coercion is also a possibility for enforcement. However, information and consultation is absolutely necessary for all parties involved.

A detailed account of the course of the discussion can be found in the conference report.