Oliver Rapf is a leading policy expert on European building performance, with long‑standing experience shaping the Energy Performance of Buildings Directive (EPBD) and related climate legislation. His work spans energy efficiency, deep renovation strategies and corporate advisory roles, helping multinational companies navigate the transition to zero‑emission buildings. He is also active in major international networks and advisory bodies, including the Global Alliance for Buildings and Construction, where he contributes to global policy alignment and knowledge exchange.

A recognised voice in the field, Mr Rapf is a frequent speaker, moderator and author on pathways to zero‑emission buildings, life-cycle carbon reduction and the practical implementation of European building policy. His career reflects a sustained commitment to accelerating climate‑aligned transformation in the built environment through evidence‑based regulation, strategic advocacy and collaboration across public, private and international stakeholders.

BUILD UP (BUP): Buildings Performance Institute Europe (BPIE) has long advocated for a more ambitious Energy Performance of Buildings Directive (EPBD). From your perspective, what are the essential elements that Member States must prioritise to translate the EPBD’s zero-emission buildings (ZEB) definition into a credible, enforceable national framework that genuinely accelerates decarbonisation?

Oliver Rapf (OR): The introduction of the ZEB standard in the EPBD establishes a new paradigm for the decarbonisation of the European building stock. By defining a harmonised endpoint for energy and emission performance, the ZEB standard aligns technical, regulatory, and financial instruments into a single integrated trajectory. To translate the ZEB concept into a credible and enforceable national framework, Member States must anchor it in clear, quantified and cost-optimal thresholds. This means legally defining maximum levels for total annual primary energy use and, at least for new buildings, life-cycle global warming potential indicators. Just as importantly, countries must adopt transparent and harmonised calculation methodologies, clearly define building and energy system boundaries and align primary energy and emission factors with national energy mixes.

Equally critical is embedding the ZEB standard within a broader governance ecosystem. National building renovation plans (NBRPs) must use ZEB as the strategic endpoint. Minimum energy performance standards (MEPS) must progressively transform the worst-performing buildings towards this endpoint, and energy performance certificates (EPCs) must make compliance visible and verifiable. At the same time, Member States must differentiate between new and existing buildings, support deep renovations with financial and technical tools and integrate energy flexibility and smart technologies so buildings actively support grid decarbonisation.

BUP: With Member States updating regulations ahead of the EPBD transposition deadline (May 2026), what do you see as the biggest challenges and most promising approaches for implementation?  

OR: A significant challenge that some Member States face is a lack of political attention to an effective transposition and implementation. The EPBD has the potential to deliver benefits that help Member States achieve many of their strategic objectives. Higher energy security and a much lower exposure to the risk of strong energy price fluctuations will be one of the direct benefits of the transformation, especially as, still today, our buildings are mainly supplied by fossil fuels.

One of the most promising strategies is consulting stakeholders who have a role in the transformation. Companies, citizens, and municipalities will all have ideas on how to design implementation based on their context, and this collective intelligence should be harnessed. The dialogue between policymakers and citizens is important to ensure their success, feasibility and public trust in policymaking. We see that in certain countries, there is still a lack of understanding of the EPBD provisions, which creates distrust and a negative attitude towards the Directive. Starting a public dialogue early on and ensuring sufficient inclusion of civil society will significantly help with implementation. The NBRP public consultations can serve this purpose. Member States, such as Spain, which had a structured, multiple-step public consultation, are a good example.

‘We see that in certain countries there is still a lack of understanding of the EPBD provisions, which creates distrust and a negative attitude towards the Directive. Starting a public dialogue early on and ensuring sufficient inclusion of civil society will significantly help with implementation.'

BUP: How important is EU comparability of zero-emission building standards, and what role can harmonised methodologies play in achieving this?

OR: The comparability of the ZEB standard across the EU is important on the one hand for the construction sector and on the other hand for ensuring that national and EU goals are achieved. The clear definition and timely application of the ZEB standard across Member States is essential. Member States must ensure that the ZEB standard applies to new construction owned by public bodies from 2028 and for all new buildings as of 2030. Moreover, the standard will define deep renovations as of 2030, as the EPBD requires Member States to incentivise deep renovations with higher financial support. Comparable methodologies for the national ZEB implementation frameworks across Member States will support better streamlining of EU funds and private investments for renovations. The compatible application of these ZEB frameworks is therefore important for the single internal construction and renovation market across the EU. This is a priority, especially considering its alignment with EU initiatives aiming at a better single market, such as the Construction Services Act.

The comparability across the EU can be achieved through comparable ZEB thresholds for primary energy use in Member State regions located in specific climate zones. Four distinct climate zones, such as Mediterranean, Oceanic, Continental and Nordic, could have similar and comparable thresholds. The link to ‘A’ energy class can also mean that comparable ZEB standards can deepen integration of EPCs in national frameworks, further supporting the internal single market.

BUP: How is deep renovation of existing buildings expected to transform them into ZEB in the light of decarbonisation of the EU building stock by 2050?  

OR: The EU renovation rate should accelerate, as recent data shows that we are still largely off track to achieve climate goals. At the beginning of this decade, the deep renovation rate stood at 0.2% on average in the EU. As the EU aims to achieve its decarbonisation goals by 2050, the deep renovation rate should reach 3% in the near future and be maintained at that level.

On a building stock scale, the process of transformation to the ZEB stock by 2050 can be achieved with a strategic set of actions. These include understanding the building stock condition through mapping and collecting data, creating targets and measurable progress indicators for its transition, and designing financial and support policies and measures that can launch renovations on a large scale. Carefully drafted NBRPs must serve as an important tool in transforming the entire building stock. The worst-performing buildings through deep renovation will bring the fastest results, as required by EPBD Article 9. Industrial-scale, serial renovation with off-site construction solutions will have to play an essential role.

‘On a building stock scale, the process of transformation to the ZEB stock by 2050 can be achieved with a strategic set of actions’

On an individual building basis, the transformation is impossible without analysing the specific characteristics of a particular building. Building experts and energy auditors play a central role. Renovation passports, tailored roadmaps for deep renovation of buildings in several steps, while being voluntary, should be used to their full extent. Developing pilot projects of deep renovation can be a source of practical solutions for specific building types and ownership structures.

BUP: What role do tools like digital building logbooks and harmonised performance metrics play in scaling up ZEBs?  

OR: The EPBD defines digital building logbooks (DBLs) as a centralised repository for all building-related data, including energy performance certificates, renovation passports and life cycle GWP data, to facilitate informed decision-making among stakeholders. However, their real value lies in the additional functionalities they enable, rather than just being repositories of information. They can play an important role in facilitating circular renovation. For example, with sufficient input data on building geometry, construction and technical systems, for example, from energy performance certificates, DBLs can generate high-quality automated renovation passports. DBLs can be connected to building information models, construction-focused digital product passports or digital bills of quantities, creating a database of building materials and components. This facilitates the establishment of secondary markets for construction materials, helping to minimise the embodied emissions of buildings.

A key challenge that remains is the absence of a binding legal framework and a harmonised standard for DBLs. Nevertheless, the Commission has made progress towards fully digitalising the single market for construction. This includes introducing mandatory digital product passports for construction products and launching a standardisation request procedure for DBLs, to publish them by 2028. Complementing the initiatives of the EPBD, the revised Construction Products Regulation also calls for a common tool to define and publish structured product data, enabling its integration into building logbooks, the Construction Digital Product Passport system, building information models and registries.

BUP: Looking ahead to 2030 and beyond, what changes are still needed for zero-emission buildings to become the norm across Europe? 

OR: Changes are needed across the value chain of the construction sector. Architects need to have the skills to design ZEBs, and building codes need to give the right framework for real estate developers. Renovation projects resulting in a zero-emission building stock need to be scaled up, and financing for them needs to be accessible.

But what is needed most is policy certainty. Policymakers on all governance levels need to define the path to ZEBs so that investors, owners and the construction industry know exactly where to put their priorities. The transformation of the built environment may seem like a task to make each building future-proof, but in fact, it is about making our energy system and our society future-proof and resilient. Changing our buildings for the better is essential for societal cohesion and individual well-being.