•The EPCs are rarely perceived as useful for the end-user.•The Building Renovation Passport (BRP) is intended as a document for triggering deep renovations.•Detailed renovation advice is needed to ...support the decision making process.•An extensive overview of the existing/developing BRP initiative across Europe is presented.
Lack of information and transparency increases risk and undermines investor confidence. Therefore, a systematized and optimized capture and processing of information also supports investment decision making and creates opportunities for innovation and uptake of energy efficiency and sustainability measures, processes and designs. Building passports could play a valuable role in boosting the availability of information to a wide range of market participants. Better information flows are a necessary part of improving the quality assurance system for buildings and the construction industry market overall.
The aim of the paper is firstly to set a Building Renovation Passport (BRP) definition, to explore the potential role of a voluntary scheme across EU as a key tool to help overcome this information imbalance by providing all market stakeholders, including financing institutions, providers of mortgage credit, investors and insurers with access to key building related documentation and information to properly assess the many factors impacting the overall quality of buildings. Within the presented study three initiatives currently developed across EU (Flanders, France and Germany), have been selected to be investigated in details providing an extensive overview of the process supporting the creation of a Building Renovation Passport and covering the main issues necessary for its development and implementation.
This study analysed renovation measures implemented with ARA renovation subsidy in Finland in multifamily apartment buildings. Measured energy data was used to calibrate the energy simulation model ...of the most typical renovated building from the 1970 s. For the reference building, a comprehensive set of renovation packages were applied to assess the performance of ARA grants. It was noticed that official energy performance certificates (EPC) overestimated before the renovation energy use as well as energy saving by a factor of almost 2. It was notable that in calculated EPCs, after renovation, EP-value was higher than before renovation, EP-value based on measured energy use. The main reasons for faulty energy calculations were strong overestimations in the building leakage rate and ventilation airflow rate. Renovation packages reduced EP-value by 8 % to 27 %, including lighting and appliances. Those using district heat resulted in a small increase in electricity with a flat duration curve, but the combined ground source and exhaust air heat pump showed the highest peak electricity power increase by factor 6. Exhaust air heat pump, window replacement and photovoltaic were the most cost-effective options, while packages with additional insulation faced considerably higher costs than the sum of ARA support and monthly savings could cover bank loans; thus, ARA support was clearly too small to support deep renovation. The need to improve the accuracy of EPCs in assessing energy performance to facilitate more effective financial support was a finding that can be important for any support scheme to secure the necessary funding for renovation.
•A pre and post renovation energy use analysis of almost 90,000 renovated dwellings.•The (p)rebound effects explain only partly disappointing energy renovation results.•Effectiveness of renovations ...are dependent on state of building prior to renovation.•Effectiveness of renovations are dependent on type of occupant.•Deep renovations often save less energy than expected but are the most effective.
Energy renovations often result in lower energy savings than expected. Therefore, in this study we investigate nearly 90,000 renovated dwellings in the Netherlands with pre and post renovation data of actual and calculated energy consumption. One of the main additions of this paper, compared to previous studies on thermal renovation, is that it only takes dwellings into account with the same occupants before and after renovation, using a large longitudinal dataset. Overall this paper shows new insights towards the influence of the energy efficiency state of a building prior to energy renovation, the type of building, the number of occupants, the income level of the occupants and the occupancy time on the actual energy savings, the energy saving gap and on the probability of lower energy savings than expected. We also investigate if the influence is different per type of thermal renovation measure. Some of the findings are: it is impossible to conclude which single thermal renovation measure is the most effective because this is dependent on the energy efficiency of the building prior to the energy renovation, type of building, income level and occupancy; occupants with a high income save more energy than occupants with low income; dwellings with employed occupants benefit more from improved building installations than dwellings occupied by unemployed occupants; The prebound and rebound effects are only part of the explanations for lower than expected energy savings; Deep renovations result more often in lower than expected energy savings than single renovation measures but nevertheless they result in the highest average energy saving compared to other thermal renovation measures. The results could be used for more realistic expectations of the energy reduction achieved by thermal renovations, which is important for (amongst others) policy makers, clients and contractors who make use of energy performance contracting, home owners, landlords and (social) housing associations and as a starting point to improve the energy calculation method.
•Private organizations focus on high-quality renovations and innovative financing.•An integrated service approach involving multiple stakeholders is crucial.•Innovative financial solutions are ...crucial for the success of energy renovations.•Barriers for Homeowner associations are linked to the renovation process.•Strategies of Integrated home renovation service providers were analyzed.
Across the European Union (EU), approximately 46% of the population resides in apartment buildings. A majority of these buildings are in need of energy renovation and are managed by Homeowner associations (HOAs). HOAs face distinct challenges in renovating their buildings. Integrated home renovation services (IHRS) have emerged as a potential solution to accelerate highly energy-efficient renovations for HOAs. The question arises: How do current integrated home renovation service providers facilitate energy renovations for homeowner associations, overcoming the prevailing barriers to uptake? This paper explores the current state of IHRS providers operating in four European regions with a focus on the Netherlands and Flanders. The study offers insights into the dynamics of their business models, strategies, and ways forward. The methods employed involve a combination of qualitative approaches. Fourteen business models of IHRS providers in the Netherlands, Belgium, France, and Austria were analysed, to define their strategies within the regional context. The results reveal that while public entities prioritize broad societal challenges, private models focus on operational efficiency and financial sustainability. Public-private partnerships offer a hybrid approach, blending strengths but requiring precise governance to align diverse interests and achieve comprehensive, sustainable outcomes. The findings can inform policymakers, practitioners, and researchers in developing effective and targeted IHRS initiatives in the EU.
•A systematic literature-approach to classify retrofitting is proposed.•An overview of Spain’s previous guidelines on residential retrofits is presented.•A review of financial and subsidies ...mechanisms in Spain to renovate buildings is introduced.•A literature-based matrix on retrofitting actions is presented.•A classification of energy efficiency strategies for retrofitting is proposed.
The building sector is responsible for more than 40% of final energy consumption in Europe; consequently, retrofitting existing buildings can significantly contribute to mitigate greenhouse emissions. Nevertheless, although the European Union has introduced relevant policy instruments, up to now the annual retrofit rates are considerably low with an average of 0.2% at European level. Understanding the past would support the success of the new strategies, such as the recent ones launched through the New Green Deal, which reinforces the importance of renovating existing buildings stock, as the main aim of the renovation wave.
As a starting point for assessing the main challenges to allocate the Recovery funds, this paper provides a review of Spain’s relevant literature to clearly define the characterization of the existing building stock, which actions have been typically considered under the scope of retrofits, and which strategies have been implemented until now, considering both, private and public initiatives and public financial schemes. The present work has a strong focus on energy-related strategies, although other interrelated actions are mentioned, such as accessibility measures and interior refurbishment of dwellings. Differences and similarities within these approaches are presented through the analysis of 27 relevant references of retrofitting actions and 52 references of financial mechanisms.
As in Spain 93% of multifamily buildings were constructed prior to the national transposition of the first Energy Performance Building Directive (EPBD), and therefore are in need of deep energy renovations, the retrofitting of multifamily buildings topic has been widely addressed, even though often in a disjointed manner. The study suggests that although historically there have been several recommended strategies, few are conceived as integral actions, only 15% of the intervention packages refer passive and active energy-related measures and renewable energy incorporation. Furthermore, considering the antiquity of the building stock and the advantage of addressing the topic through clusters, only 63% of the resources directly refer these actions to specific clusters among the six distinctive periods, although in most cases focusing their recommendations on buildings constructed before 1980 where the worst energy performance buildings are concentrated.
Concerning public financial and funding instruments, the research illustrates that there has been a substantial increment of programs over the last years promoting energy-related measures, renewable energy and other complementary aspects such as accessibility and interior renovations, mainly for older clusters. Nevertheless, the funds constitute only 8% of the necessary declared investments, which along with the dispersion between the different procedures and the complexity of the processes, have significantly reduced the global impact of these actions without generating robust and oriented market dynamics.
Despite the several resources found, both financial instruments and guidelines tend to describe in more detail strategies related to heating demand and consumption and not delve into other relevant actions for warmer climates, fact associated both to the dynamics coming from other countries, and to a vision of the past in which people do not consume refrigeration. This clear focus on heating loads rather than cooling could present limitations for warmer regions in the near climate-change future.
•Long-term field data for 11 existing multifamily buildings are presented.•Analysis of calculated and actual energy savings resulting from renovation of buildings.•The actual payback time was in the ...range between 3.1 and 104.8 heating seasons.
Thermal renovation of existing buildings is one of the most popular actions to decrease the energy consumption for heating and cooling. However, to the best of the authors’ knowledge, there are no long-term field studies that present the influence of hydraulic rebalancing of the heating system after the thermal renovation of the building’s envelope on the level of achieving the calculated energy savings.
This work presents the results from a field study that collected data on actual operational energy over several heating seasons, from 11 similar multifamily buildings in Poland. All buildings were thermally renovated by insulating their envelope, while for some of them the works were completed by a hydraulic rebalance of their heating system. The modernization activities were implemented with a different sequence. For another group of buildings, the hydraulic balancing of the heating system was not performed after the envelope thermal renovation. This offered an excellent opportunity to compare the actual energy performance of the renovated buildings and quantify the achieved energy savings resulting from different practices. Energy audits were performed in all buildings in order to calculate the energy use of the buildings before and after the renovations. These estimates were then compared with the actual energy savings from the monitored energy use for all renovated buildings. Accordingly, the actual energy savings range between 8.8% and 74.8% of calculated energy savings, depending on the different renovations. The actual payback time for the analysed modernization actions was longer than the calculated one, ranging between 3.1 and 104.8 heating seasons.
There is an untapped potential for reducing GHG emissions by district renovation. It needs a detailed Energy Master Planning (EMP) of the district and support for the decision-making processes. If ...applied in a comprehensive manner it can contribute significantly to reducing energy consumption and thus to a long-term sustainable development of districts and climate neutrality in our cities.The EMP typically includes combinations of energy supply and consumption, but it is equally important to understand the different solutions for district renovation. The multi-owner structure in many districts requires another set of solution finding that is embedded in potential analysis, stakeholder analysis, participative planning, and multi-actor-Management. A district near Winterthur, Switzerland was used as a case study. Site visits and structured interviews with key stakeholders were used to collect data which was then used to model the technical-economic situation and to determine the possibilities for the future.
Retrofit of existing housing increases the possibility of meeting Sustainable Development Goals. Improving quality of life, minimising energy consumption and increasing productivity in buildings ...process with the aim of affordable housing (social, environmental, and economic sustainability) set new demands for renovation amongst residential housing in Norway. Most studies to date emphasised on mitigation of CO
2
emissions in building sector through building renovations. However, recent studies started evaluating why such renovation plans may not be considered by property owners. This study investigates potential barriers and motivations for Sustainable Building Renovations (SBR) from house-owners' perspective and discusses the role of urban Facility Management (FM) in promoting SBR. Results from a questionnaire survey with 341 citizens in Trondheim city, Norway, confirm economic issues as the main barrier for SBR with respondents suggesting different forms of financial support to resolve these barriers. Social engagement of citizens with public/private partners and neighbours illustrates the collective motivation for SBR. This requires an intermediary role like urban FM engaging citizens to co-create their needs in urban areas with public/private sectors. The output of this study helps to promote urban FM engaging with SBR targets through renovation of neighbourhoods.
This open access book delves into the topic of monitoring the effectiveness of building renovation policies within the European Union (EU) using indicators. Given the substantial environmental impact ...of existing buildings on energy consumption and greenhouse gas emissions, decarbonizing them is imperative for achieving climate neutrality in Europe. The use of indicators for monitoring decarbonization progress and evaluating policies emerges as a valuable tool, ensuring the efficiency, effectiveness, and alignment of building renovation policies with broader sustainability and climate objectives. Additionally, this approach facilitates evidence-based decision-making, promotes accountability by Member States (MSs), supports the realization of long-term goals, and actively involves the public in these vital initiatives. The European Commission is actively engaged in this realm, releasing a framework of optional indicators in 2019 and subsequently refining it during the review of the Energy Performance of Buildings Directive. The evolving framework seeks to encompass both mandatory and optional indicators, posing greater challenges for EU MSs in monitoring the impact of their national building renovation policies and the progress of decarbonizing their building stocks. This book offers insights into these developing indicator frameworks, assesses the availability and quality of data in the case of Spain, and suggests areas of improvement and innovative approaches using emerging technologies to enhance data. The target audience includes diverse stakeholders such as central government administrations, regional and municipal authorities, data-collecting institutions, urban planners, researchers, and citizens interested in comprehending the impact of building renovation. By addressing this broad audience, the book aims to foster a more inclusive and well-informed discussion on building renovation and the decarbonization of the European building stock.
•Multi-objective optimisation is an efficient method in energy and cost-optimality analyses of buildings.•It is more cost-effective to improve the energy performance of the HVAC and energy systems ...than the energy performance of the building envelope.•Heat pump systems are more cost-effective and energy efficient than district heating.•External financial support is needed to encourage apartment building owners to conduct deep renovations towards nZEBs.
The paper presents cost-optimal energy performance improving measures conducted in deep renovations of typical Finnish (cold climate) brick apartment buildings, built in the 1960’s. The study discusses the effects of different renovation measures on the energy performance and economic viability in a selected building. Energy performance is studied from the primary energy consumption’s perspective and cost-effective renovation measures to meet higher energy performance criteria are also studied. The cost-optimal renovation concepts to meet different energy performance criteria were determined from over 2 billion potential renovation measure combinations by using sophisticated simulation-based multi-objective optimisation (SBMOO) analysis, utilising the advanced Pareto-Archive NSGA-II genetic algorithm, as the main research method. The SBMOO analysis was used to minimise the primary energy consumption and the net present value of life-cycle cost over a 25-year discount period simultaneously. The results indicate that the cost optimum renovation solutions of the brick apartment building stock provide the same energy performance criteria as the current national minimum energy performance requirements of new apartment buildings. According to the study, the investments should be focused on high performance renewable energy production systems, which deliver the best return on investment. External financial support mechanisms are also required to encourage apartment building owners to conduct deep renovations towards nearly zero-energy apartment buildings.
PDF
