‘The key ingredients for a transformational NBRP aren’t so much about new technology but about new financing models and business approaches to make renovation feasible and attractive’: Risto Kosonen, Professor from the Department of Energy and Mechanical Engineering, at Aalto University, Finland.
Prof. Risto Kosonen is an internationally recognised HVAC expert whose work centres on high-performance indoor environments and building energy efficiency. A former R&D/business-development leader in industry (20 yrs), Risto has headed numerous university-industry research consortia for 25 years, producing 320+ refereed papers and holding nine European patents on indoor-climate and energy systems. His current projects span digital twin and IoT-driven energy optimisation for buildings and neighbourhoods. Prof. Kosonen serves as Vice-President of REHVA, President of SCANVAC and of the Finnish HVAC Federation, and chairs Finland’s Indoor Climate Association. Kosonen frequently keynotes global conferences (e.g., President, ROOMVENT 2018), reviews Horizon Europe proposals and evaluates structural-fund research. His honours include the REHVA Professional Award, the Scanvac Rydberg Gold Medal and election as REHVA Fellow. Recently, Risto co-authored the Aalto University report Talotekniikka 2030 – Regulaation vaikutukset, a practical roadmap (concrete technical and business actions) for Finland’s HVAC and construction actors to support the EPBD implementation for timely meeting the overarching energy and climate goals.
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BUILD UP (BUP): What three ingredients do you see as decisive for turning a merely compliant plan into a truly transformational National Building Renovation Plan (NBRP)?
Risto Kosonen (RK): First, we need to tackle the financing challenge, especially for the residential sector. The technology to save energy and cut CO₂ exists, but many apartment buildings are in less attractive areas or owned by people with low incomes (like retirees) who struggle to finance renovations. Some buildings have great potential for savings but can’t get loans because their value is too low. Ensuring funding is available for these cases, through innovative financing, subsidies or guarantees, is absolutely critical.
Second, we should provide clear, pre-designed renovation solution packages and technical support for building owners. Renovating apartment buildings can be complex, so it helps to offer “ready-made” upgrade packages that owners can easily choose from, covering insulation, heating systems, ventilation, etc. Ideally, there would be companies or organisations to guide homeowners through the process.
Third, we should encourage large-scale or community-level renovation approaches instead of isolated, one-building-at-a-time projects. For example, renovating multiple buildings in the same area or housing block as one project can significantly reduce costs through economies of scale. It also attracts more interest from contractors, even smaller construction companies, because the projects are bigger and more worthwhile. In a larger area renovation, we can consider advanced solutions like shared energy systems, waste-heat recovery, or energy storage serving a group of buildings, which wouldn’t be viable for single buildings alone. This kind of neighbourhood or ’small energy community’ renovation strategy can be transformational in cutting costs and improving efficiency at scale. In summary, the key ingredients aren’t so much about new technology – we already have good technologies, but about new financing models and business approaches to make renovation feasible and attractive.
BUP: Considering that the NBRP must include specifications on key benchmarks, including the Minimum Energy Performance Standards (MEPS), which will act as milestones for existing buildings to reach ZEB performance level by 2050, how can Member States pitch MEPS high enough to meet 2050 goals, yet low enough that building owners comply early rather than in a last-minute rush?
RK: It’s a delicate balance. The standards must be ambitious, we need all buildings at a zero-emission level by 2050, but they also have to be introduced in stages so that owners do not wait until 2049 to act. In practice, that means setting clear interim targets and gradually tightening the requirements over time. For example, in Finland we analysed the entire building stock to see what it takes to cut emissions by around 80% by 2050. That analysis showed which building types and age groups should be renovated first and what solutions have the biggest impact. Using that kind of insight, a government can set early Minimum Energy Performance Standards (MEPS) that focus on the worst-performing buildings or the most impactful upgrades first, then ramp up the stringency in steps. This way, building owners are prompted to start improvements long before the final deadline. Clarity and credibility of the targets are crucial. In my view, it helps to separate the energy efficiency requirement from the carbon/emissions requirement when defining these standards. Owners should clearly see that first they need to reduce energy demand, and separately, that by 2050 the energy supply or remaining use should be zero-carbon. If you mix energy and emissions into one metric, it can create loopholes, for instance, someone might claim a building is ’zero emission’ by buying green electricity while still wasting energy. To avoid this, set a clear energy performance standard (to encourage actual efficiency) alongside an emissions trajectory. In Finland, we’ve observed that people tend to follow the law if it’s clear and firm. So if MEPS are well-communicated and legally confirmed, many owners will plan ahead rather than procrastinate. To reinforce this, authorities can offer incentives for early adopters or penalties for those who delay until the last minute. Also, avoid setting the initial bar so unrealistically high that owners feel paralysed. The first step should be high enough to matter but still attainable with current technology and reasonable investment. If owners see that meeting the standard is feasible and beneficial (for example, lower energy bills or higher property value), they’re more likely to act now.
BUP: The process of formulating the National Building Renovation Plan starts with a building-stock snapshot. Which data-governance model secures quality and privacy while enabling EPCs and Renovation Passports at scale?
RK: The key is to use robust national data sources to get a full picture of the building stock, without having to individually audit every single building. In Finland we have a good model: our national statistics authority maintains a database of all buildings, their construction year, size, type, etc. essentially the basic characteristics of the entire building stock. We know how many buildings were built in each era and what energy code was in force at that time. This allows us to estimate the likely energy performance of buildings even if they don’t have an EPC yet, simply because buildings constructed under the same code have similar efficiency levels. Using such aggregated data respects privacy because you are not disclosing any one homeowner’s energy usage, users are working from generalised building characteristics and code requirements. We then combine or cross-analyse this with the EPC database for the buildings that do have certificates. By correlating the two, we can fill in the gaps with reasonable accuracy. For example, if we know a 1980s apartment building typically has a certain energy rating and we have some actual EPCs from that category, we can infer the performance of similar buildings that haven’t been certified yet. This approach ensures quality data at scale, you’re leveraging real statistics and real certificates to model the whole stock. In terms of data governance, it’s about centralising these datasets (the building registry and the EPC registry) in a way that they talk to each other while keeping personal data secure. Typically, a public agency or a trusted entity can manage the data merging. Individual building owners’ data can be anonymised or aggregated at a regional or building-type level when analysing trends, so privacy is maintained. The outcome is a comprehensive snapshot of the country’s buildings without having to pry into each homeowner’s records. Such a model enables issuing EPCs and Renovation Passports at scale, because once you know the baseline of each building (or each category of buildings), it is possible to automatically generate recommendations. Essentially, you pre-fill a lot of information from the national database, and then an energy expert can validate and refine it when creating an EPC or a Renovation Passport for a specific building. This balances data quality, coverage, and privacy. This results in a living map of the building stock, one that’s data-driven and updatable, which is exactly what a national renovation plan needs.
BUP: The concrete implementation and realisation of the NBRP is carried out via several interrelated policy instruments of the EPBD. Where do you see real synergy, and possible overlap, between Renovation Passports, upgraded EPCs, SRI and the coming Zero-Emission Building performance level?
RK: I see all of these as parts of the same puzzle. They should work together in one coherent process. In fact, it would make the most sense to merge them into a single integrated framework rather than running separate processes for EPCs, Renovation Passports, and SRI. At the end of the day, they all assess aspects of a building’s performance. The Energy Performance Certificate (EPC) looks at energy efficiency, the Renovation Passport lays out a long-term upgrade roadmap, the SRI evaluates how smart the building’s systems are, and the zero-emission building performance level sets the ultimate energy and carbon target. These are interlinked measures of essentially the building’s journey to sustainability. If each is done in isolation, you risk duplication, confusion, or even conflicting recommendations. In practice, the synergy comes from using a common data set and assessment to serve multiple purposes. For example, when an assessor evaluates a building, you could simultaneously gather information for the EPC rating, identify improvements for the Renovation Passport, check the digital systems for SRI, and see how far the building is from Zero-Emission level. Rather than four separate visits or reports, you’d have one holistic evaluation that feeds into all outputs. This not only saves time and cost, but also ensures consistency, the advice in the Renovation Passport would naturally align with achieving a better EPC class, improving smart capabilities, and reaching zero emissions. I think from an engineering and practical point of view, it’s logical to combine these. Perhaps the energy certificate process can be expanded to include smart-readiness and a pathway to zero emissions, effectively embedding the Renovation Passport concept into it. This way the building owner gets one comprehensive report, this could be called an enhanced EPC or a building renovation roadmap, that includes energy performance, a step-by-step renovation plan, the building’s smart features, and how to reach zero emissions. Real synergy comes when these tools reinforce each other: the Renovation Passport tells you how to improve stepwise, the EPC and ZEB criteria tell you what target to aim for, and the SRI ensures you leverage smart tech along the way. Combined, they provide a powerful, unified guidance for transforming a building, whereas separately, they might overwhelm or confuse building owners.
BUP: Draft NBRPs are due 31 Dec 2025 and will be reviewed by the Commission in mid-2026, finalised by Member States by end-2026, then revised every five years. Which indicators keep a plan alive rather than a PDF on a digital shelf?
RK: To keep a renovation plan alive and effective, we need to continuously track a set of key indicators that show whether we’re on course and use those to update the plan regularly. One fundamental indicator is the renovation rate: how much of the building stock is renovated each year or during each five-year period. We calculated how many buildings need to be renovated in Finland to meet the new EPBD targets, and from that you get an annual or periodic goal to hit. So, monitoring the percentage of buildings (or floor area) upgraded toward zero-emission levels over time is crucial. If the rate is lagging behind the plan’s expectations, that’s a red flag and the plan needs adjusting or extra measures.
Another core set of indicators revolves around energy and emissions outcomes. I would track the overall reduction in buildings’ energy consumption (for example, average kWh per m² dropping across the stock) and the reduction in greenhouse gas emissions from buildings. It’s important to track energy efficiency improvements separately from emissions reductions. This was a point we discussed in Finland, if you only look at a combined metric, you might miss the fact that energy use is not dropping, even if emissions are, due to cleaner grids —or vice versa. So, have an indicator for energy demand reduction (which tells you if renovations are saving energy) and another for CO₂ emission reduction (which tells you if we’re on track to hit climate goals). Both are needed to keep the plan honest and comprehensive. We should also include indicators of the plan’s wider impacts and implementation progress. For instance, financial indicators like the total investment in renovations (public and private) can show whether funding is flowing at the scale expected. And socio-economic indicators make the plan feel real to people, in our study we even calculated how many jobs the renovation wave could generate. Tracking the number of jobs created in the construction/renovation sector, or the growth of businesses providing renovation services, can indicate that the plan is not merely a document, but a driving force in the economy. Similarly, you might measure things like improvements in indoor climate or health outcomes from better buildings, though those are harder to quantify regularly.
Finally, an indicator I find important is compliance or uptake of available tools: for example, the share of buildings that have an EPC or Renovation Passport. If by a certain date a high percentage of buildings have a Renovation Passport outlining their future upgrades, that suggests the plan’s mechanisms are actively in use. If these numbers are low, the plan risks sitting on the shelf. Essentially, a plan stays alive if we are measuring progress and acting on it. By regularly publishing these indicators — renovation rates, energy saved, emissions reduced, funds invested, jobs created, and the number of building owners engaged, authorities and stakeholders can hold each other accountable and keep the momentum. When something is off-track, the plan can be revised — as expected every five years, or sooner if needed — to introduce new measures or adjust ambitions. In this way, the NBRP becomes a living document, guided by data and results, rather than a static PDF that’s quickly forgotten.
