Contracting as a instrument for renovation

Development of contracting models for comprehensive renovation service packages.

Content Description




Part A:


Purpose of this project was the further development of contracting models for comprehensive renovation service packages which comply with the program objectives "house of the future". That means in the sense of energetically and ecologically optimized as well as socially acceptable renovation services. For this reason the broader feasibility of energetically and ecologically optimized renovation is possible. Particularly in the field of public buildings contracting can - due to financial bottlenecks - act as a "door opener" for proceeding innovative measures. Through the link of building renovation with contracting models and the best utilization of the renovation date, the user can expect an altogether cheaper renovation with higher quality. Finally such a further development of the instrument "contracting" contributes to the market diffusion of innovative technologies.

Content and goals:

The analysis of previous used company cooperation models in combination with contracting projects and the analysis of previous comprehensive international contracting projects were primarily important. Furthermore the analysis of alternatives and restraints to the used contracting models as well as the aimed experts questioning concerning the topic "contracting and comprehensive renovation" were the basic tasks in the first place. In addition to this, new contracting models had been developed, discussed with representatives and tested for the practical suitability at the workshop. Subsequent to the workshop (1st of July 2003) the first drafts of new contracting models were revised and adjusted. As a result three different contracting implementation models are available right now which had been presented to a broad public at the information event on the 10th of December 2003.

Intended and reached goals:

  • Three variations for extended contracting models suitable in practice. Properly forms of organization and cooperation had been investigated (e.g. formation of working groups, building companies as contractors, leasing projects) as well as treatment of contractual aspects.
  • Exchange of information and experiences between the two up to present separately acting "communities" - the "technical innovators" in the "house of the future" and the "economic optimizers" of the contractors.
  • Increase of the awareness of comprehensive contracting services and first basic approaches for the readiness of contractors, the building industry as well as of architects, planers and leasing companies to implement such extended contracting models.
  • Conclusions and proposals for the further market preparation.

Method and data basis:

At the beginning the requirements and the legal and economic framework conditions, the potentials and restraints for new organization models of contracting in the sense of the project goals had been analyzed. Previous contracting projects, contracting models, programs and experiences served as a basis. After that and by means of the experiences a first draft of contracting models was made which are qualified for a broad distribution and successful application by different groups of actors. The network and information distribution referring the topic "comprehensive contracting models" happened at a workshop and information event to give the target group an understanding of the models. Proposals for the further distribution and market preparation for extended contracting models had been elaborated at the end. The data basis for the project are the conclusions out of the interviews, the project experiences of the grazer energy agency as well as the results from the research activities. Relevant literature which served for the processing of the project difficulty can be found in the bibliography.

Part B:


The relevance of building measures in the frame of contracting is at the moment not very significant. Market potentials and the demand of customers (especially public building owners) however exist. Within an international research for corresponding projects only few projects with rather "test character" could be found. Only one program which is just in creation has the same focus (energy saving partnership plus of the Berlin energy agency). Using the phrase "public private partnership" forms of cooperation and financing (amongst contracting) for the public hand are now being discussed and tested which make it possible to connect energy saving and constructional renovation measures. Due to the interviewing of 25 experts, beneath contracting providers, building companies, building owners, planers and financiers restraints and promoting factors for the integration of constructional and energetic renovation measures in contracting projects had been identified.

The restraints are the following:

  • The so far lacking of experiences with such projects
  • The high effort (planning effort, effort to submit an offer) prior to a complex project
  • Insufficient trust in the services of the corresponding industry sector (construction or contracting)
  • Know how deficit for constructional topics (especially building physics), which contractors and financiers have particularly
  • The refinancing time of the contracting project is considerably extended, construction subsidies and additional financial considerations are necessary
  • Many actors do not have the awareness of comprehensive renovation services

Promoting factors are:

  • The attractiveness of the contracting characteristics e.g. the guaranteed building performance after the renovation (especially savings guarantee for energy costs), maintenance, one contact person for the whole project execution and ongoing supervision of the installations, comfort guarantees and so on.
  • Common optimization of investment and operating costs - holistic consideration
  • Important clients for comprehensive contracting projects are public institutions because their buildings show similar use and problems
  • Contracting projects and ecological guidelines can be connected very well

Building on the results of the interviews and the own project experiences (contracting and building) three implementation models with different actors constellations could be developed. The goal to improve extended contracting models and to prove their practical suitability as well as to guarantee an experience and information exchange could be reached thanks to the executed events with active participation of representatives of nearly all relevant groups. The attention of the participants for extended and new contracting models as well as an interest for the topic and the implementation in the own business area could have been stimulated. Because of this the basis was developed to further distribute such contracting models to interested people in the future and to deepen the already developed cooperation.


It can be assumed that comprehensive contracting offers including constructional measures are interesting for building owners especially for those in the public sector and are now requested intensively. The various actors groups particularly building companies interested in new business fields recognize the big chances and market potentials in these extended offers. Some contracting companies are also interested because from their point of view an overall solution should be realized if a renovation project is executed. Others want to focus on their core competencies (e.g. energy saving up-to-date plants or control technology) that means a certain polarization at this company group is visible. The further application of innovative renovation services and correction of partly existing information deficits should be divided firstly in continuing education actions for actors which already work in the contracting field and are interested in comprehensive contracting or mixed financing forms. Secondly concrete actions for "newcomers" especially in the building sector are necessary. A proposal for the realization in terms of a workshop series with modules was made in the frame of this project.

An important result while concentrating on the models is, that it is much more easier for contracting companies to guarantee for an upper level of energy costs at a building which is renovated to a low level energy standard (using passive house components especially high insulation, ventilation system with heat recovery) than it is for an "as usual" renovated building. This follows because very low energy ratios can only be reached if the energetic construction measures (e.g. insulation) and the efficient installations cooperate. At energy efficient buildings the ventilation heat loss is playing an important role. The loss is optimized through the ventilation system with heat recovery because of the constant supervision by the contractor and can be influenced through the control technology. Furthermore usual consumption fluctuations in the range of 10-20 % of the yearly consumption do not have an impact on the overall costs because of the lower total consumption. The costs for financing and services appear in the front, also the step towards fixed overall costs (independent of the consumption) is possible - especially for buildings near the passive house standard. The quality control at the execution and the inspection of the construction and installation measures is gaining importance therefore also quality assurance instruments like thermography and blower door tests.

Project Partners

Project manager: DI Gerhard Bucar
Grazer Energieagentur
  • Christian Gummerer
    IFF/IFZ Interuniversitäres Forschungszentrum für Technik, Arbeit und Kultur
  • Mag. Hannes Piber
    Trigon Entwicklungsberatung für Mensch und Organisation (Reg. Gen.m.b.H)


DI Gerhard Bucar
Grazer Energieagentur Ges.m.b.H
Kaiserfeldgasse 13, 8010 Graz
Tel: 0316/811848-0
Fax: 0316/811848-9