Developing portfolios is not an option, but rather an obligation for every project developer to contribute to ecological and social sustainability.
Depending on how it is calculated, Germany's building stock accounts for around 30 to 40 percent of the country's total energy consumption. We can only achieve our climate targets if we make this stock fit for the future again. That is our mission. As a landmark, we have therefore defined our own goals in addition to the global sustainability goals, which we are implementing in the areas of ecological construction, renovation, and climate-friendly operation of buildings and neighborhoods. When dealing with existing buildings, this means:
- Postponing the CO₂ stranding date according to CRREM by at least ten years
- Reducing final energy consumption by at least 30 percent compared to the time of purchase
- EU taxonomy compliance
- BREEAM certification of at least "very good" for existing buildings
But the mission does not stop at energy-efficient renovation: in addition to high energy requirements and a poorCO₂ balance, older office buildings also tend to score poorly in terms of comfort. This has an impact on the rental situation and thus also on cash flow. Spending time in an existing property must be enjoyable again – the well-being of users is therefore just as important to us as contributing to climate protection.
Don't be reckless, be courageous!
And how? "Just do it, be brave," says Frederike Krinn, head of the Rhine-Main branch of Landmarken, which is intensively involved in sustainable portfolio development. Commercial real estate in particular offers a wealth of opportunities for "placemaking," i.e., creating and repositioning places with a focus on sustainability: "It would be negligent of us not to take care of this!"
A good example is one of our portfolio developments in Bonn: over a period of almost two years, we pushed ahead with the energy transformation concept for the Lindeblock and tried to convince potential users that it also offers the right added value in terms of the cost-benefit factor. Ultimately, it was precisely these aspects that tipped the scales in favor of the City of Bonn signing the lease. This shows us that we are on the right track with our Manage-to-ESG concept in portfolio transformation!
The Lindeblock in Bonn, built in 1993 with around 8,200 m² of rental space, is currently undergoing design upgrades and energy-efficient renovations. In addition to apartments, the mixed-use complex houses a library, a bicycle shop, and a post office. However, office space dominates, much of which stood vacant – until the city of Bonn leased it (around 5,000 square meters) for at least ten years and took it over in April 2025. The city's decision to lease the space was based on the energy efficiency measures in the building, such as the installation of a photovoltaic system, the installation of heat pumps for energy supply, and the use of a smart metering and measurement concept. The inner courtyard will also be upgraded and landscaped to improve its amenity value.
"Transforming existing buildings is urban repair. It's more than just putting on a band-aid; it can heal the entire environment."
Frederike Krinn, Branch Manager Rhine-Main, Landmarken
Energy design with the help of artificial intelligence
Augusta 33 is located in Mannheim, around 170 km up the Rhine. The approximately 28,000 m² listed ensemble was upgraded by our sister company The Urban Village with new interior design and color concepts, and we improved its energy efficiency: Through the minimally invasive installation of sensors, all important data on the building physics and existing building services engineering in the building was recorded and, with the help of artificial intelligence, an individually tailored energy design was created.
"We meet the needs of existing and new tenants under one roof, so that everyone feels really comfortable," says Frederike Krinn. "The companies we talk to want to bring their employees back to the office, not through quotas and regulations, but through culture and offers."
That's why we will continue to expand our efforts in the building stock. "We are looking for properties that need a new concept: older, only partially leased buildings that can be made really cool again with well-balanced, structured measures while remaining in operation."
