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Refurbishment strategies for large building portfolios

Cost effectiveness is a key factor in the refurbishment in the energy-efficient refurbishment of large building portfolios. dena supports the housing industry, municipalities and

managers of large real estate portfolios in the analysis of their building portfolios and the development of meaningful strategies.

Cost efficiency is key

Refurbishment of larger building portfolios

dena has a variety of services that help owners and managers of larger building portfolios to organise energy-efficient refurbishment: refurbishment roadmaps, for instance, permit a realistic forecast of how, in which period, and at which cost the portfolio can be purposefully refurbished.

It will be necessary to exploit the entire range of energy-saving potential in order to meet the Federal Government’s ambitious target of achieving a largely climate-neutral building portfolio by 2050. The owners and managers of larger building and real estate portfolios in the states and municipalities are facing stern challenges. This applies also to the housing industry. An important factor is that the energy-efficient refurbishment plans must be implemented cost effectively, to suit requirements and in a socially acceptable manner.

dena offers its expertise and advice to public sector housing companies and real estate managers. The development of long-term refurbishment strategies is advisable, especially for large real estate portfolios that sometimes comprise several thousand properties.

The refurbishment roadmap points the way.

So-called Refurbishment Roadmaps (RRM) can be used to analyse entire building portfolios. The refurbishment requirements of each building are identified based on defined criteria such as energy savings and investment costs. The RRM indicates in detail which buildings should be prioritised for modernisation for reasons of cost effectiveness, and which ones already satisfy a comparatively high standard. This gives owners and managers a clear overview of how and in which period they can purposefully refurbish their portfolio, how much it will cost, and how much they can save.

Services for contracting and municipalities

Anyone looking to use external service providers to improve the energy efficiency of their building will find competent advice at the Centre of Expertise for Building Contracting. In addition, dena's energy and climate protection management for municipalities helps public administrations to develop their focuses and strategies to increase energy efficiency in buildings.

A focus on industries and districts

dena recently launched an industry-specific pilot project that is designed to advance the energy-efficient refurbishment of hotels and accommodation facilities. Moreover, it will become increasingly important to expand the scope of thinking beyond individual buildings to encompass the energy-efficient development of quarters, districts and even entire cities. dena has its eye on these goals as well.

Projects on the topic

Energy-Efficient Municipalities

Municipalities which consume less energy save money and promote climate protection. With its "Energy-Efficient Municipalities" project, dena aims to motivate local communities in Germany to introduce systematic energy and climate protection management. dena offers certification as a dena Energy-Efficient Municipality to cities and towns that have successfully introduced such a management system.


  • Project start: 2009
  • dena organises series of consulting events in numerous municipalities all across Germany
  • Three certified dena energy-efficient model municipalitities

Federal-state dialogue event: Contracting

Energy contracting is an effective instrument for increasing energy efficiency in buildings. Contracting reduces energy costs, ensures low energy consumption and cuts CO2 emissions, This makes it an important instrument for the success of the energy transition. In order to tap into contracting potential all over Germany, dena operates the Centre of Expertise for Contracting for Buildings with support from the Federal Ministry for Economic Affairs and Energy (BMWi).


  • Project start: 2002
  • More than 30 successful energy efficiency contracting projects for federal real estate have been launched
  • They guarantee savings of around 15–60 percent of the building's energy costs (39 percent on average) and average CO2 reductions of 37 percent.
  • 2010: Founding of the Centre of Expertise for Contracting
  • Established group of experts from state energy agencies, state authorities, and state offices 

Check-in Energy Efficiency pilot project

dena's pilot project demonstrates the energy saving potential in the accommodation sector and ways to exploit this potential. Concrete refurbishment properties are to serve as examples of economically, ecologically and socially acceptable concepts for the "hostel of the future".


  • Project start: 2015
  • Number of participants: 30
  • Funded by: Federal Ministry for Economic Affairs and Energy
  • Partners: Viessmann, Daikin
  • Media partners: Hotel & Technik, Superior Hotel