Many housing companies are facing the challenge of operating their heating systems more efficiently and in a climate-friendly manner. At the same time, traditional refurbishment measures are often difficult to implement. Where do you currently see the greatest leverage?

Dr Dirk Then:
The pressure to act in the existing building stock is undeniable. Emissions must decrease, regulatory requirements are increasing, and at the same time investment budgets and skilled labour are limited. A comprehensive energy refurbishment of the entire housing stock is therefore hardly realistic in the short term. This is precisely where digital solutions come in. They represent an economically viable and rapidly effective complement to structural measures.

Digitalisation enables existing heating infrastructure to be used far more efficiently. At the same time, it creates a reliable data foundation that allows decisions and investments to be approached strategically rather than based on assumptions.

Why does data availability play such a central role?

Dr Dirk Then:
Because the operation of many heating systems in existing buildings is still based on assumptions rather than on the actual behaviour of the building, the system and its occupants. Temperatures, flow rates or heating response times are rarely recorded continuously. Instead, the system is configured once and then often not reassessed for years.

Without transparency, there is no basis for well-founded decisions. Only when operational and usage data are continuously available does it become visible where energy is unnecessarily consumed, where systems are suboptimally configured, or where comfort and efficiency diverge. Data is not an end in itself; it is the prerequisite for targeted, economically sound and structured optimisation.

What distinguishes a data-driven approach from traditional optimisation methods?

Dr Dirk Then:
The key difference lies in the transition from static experience-based values to a dynamic understanding of real system operation. Traditional optimisation methods often focus on individual adjustment parameters and one-off interventions. They inevitably remain static.
A data-driven approach, by contrast, follows a systemic principle. Buildings, technical systems and usage patterns are no longer viewed in isolation, but evaluated in their interaction. Efficiency is not achieved through isolated adjustments, but through continuous, transparent management of system operation.

What strategic benefits does this approach offer housing companies?

Dr Dirk Then:
The benefits extend far beyond short-term savings. By combining monitoring, analysis and intelligent control, energy consumption can be systematically reduced and CO₂ costs lowered. At the same time, legal requirements – for example under the German Building Energy Act or the CO₂ Cost Allocation Act – can be demonstrably fulfilled.
Even more important is the improved quality of decision-making. Instead of relying on blanket assumptions, planning becomes fact-based. Heating systems can be dimensioned according to actual demand rather than oversized due to uncertainty. This increases investment security and improves emission efficiency – in other words, the capital deployed per tonne of CO₂ avoided.

The building stock is highly heterogeneous. Do digital solutions quickly reach technical or economic limits?

Dr Dirk Then:
Diversity in existing buildings is a reality. There is no single “typical” heating system or “standard” apartment building. Usage patterns, technical configurations and building physics vary significantly.
That is precisely why we rely on retrofit solutions. Smart components can be easily installed and combined with existing systems. This makes it possible to establish a data-based control loop even where only manual adjustments were previously possible. The decisive factor is that economically usable data can be collected quickly and reliably, despite differing starting conditions.

What role does heat distribution within the building play, particularly in older systems?

Dr Dirk Then:
Heat distribution is a key lever for efficiency. In many existing buildings, traditional hydraulic balancing was never carried out, or its effects have diminished over time.
Digital solutions enable continuous, adaptive balancing that aligns with the actual heating demand in each room. The control system reacts dynamically to changes without the need to replace valves or manually readjust systems. Particularly in unsanctioned building stock, this can deliver measurable efficiency gains. At the same time, regulatory requirements can be met and funding opportunities utilised – a clear advantage for property owners.

How important is a holistic approach in implementation?

Dr Dirk Then:
It is crucial. Isolated measures rarely achieve sufficient impact in existing buildings. What matters is a systematically effective overall concept that connects operational optimisation with strategic planning. Only through this interplay can digital solutions unlock their full potential and generate sustainable efficiency gains.

What role will data-driven optimisation play in the future of existing buildings?

Dr Dirk Then:
A central one. Requirements for efficiency, transparency and verifiability will continue to increase, and the existing building stock remains decisive for the heat transition.
Without reliable data and intelligent control solutions, the available efficiency potential cannot be realised. Smart digital solutions are therefore not an optional add-on, but a fundamental prerequisite for a planned, secure and economically viable transformation of energy supply in existing buildings.