Conference Agenda

The European Union's Renovation wave and the EPBD often exempt listed buildings and those in heritage areas from minimum energy performance standards. As a result, there is little incentive to improve the energy efficiency of these buildings, despite their poor performance. This places a burden on occupants wanting to reduce energy consumption and costs.

Enhancing the energy performance of dwellings poses challenges for home-owners, especially for those with historic homes. Conventional renovation methods may not be suitable due to the need to preserve architectural appear-ance. This requires specialized solutions.

The field of heritage conservation is inherently cautious and conservative, and good examples are needed to drive change. The aim of this study was to identify current practices in the improvement of energy performance of herit-age homes. To this end, 11 fully renovated residential buildings were thor-oughly examined to assess the energy savings achieved through the renova-tion work and to understand the challenges that arise during the renovation process.

Results indicated that the structures of the buildings were damaged prior to renovation, which makes it typical for heritage homes to require some struc-tural changes and repairs. Before the renovation, the greatest heat loss in a heritage home—over half—occurs through external walls and windows, mak-ing it advisable to focus on reducing heat loss in these areas first. The average reduction in the energy efficiency index was 31%, and the average reduction in heat demand was 43%. With current practices, the energy performance value of a heritage home remains twice as high as that of a new home. The potential for improving energy performance has not been realized due to in-sufficient insulation of the building envelope and a failure to renovate tech-nical systems, including ventilation. Ventilation with heat recovery plays a crucial role in improving energy efficiency and indoor climate. On average, it would have been possible to enhance energy performance by over 20% with-out significantly damaging or altering the heritage values.

From a purely building conservation perspective, the final results of the herit-age homes can be considered good. However, based on the life cycle costs for homeowners, the reduction in the building's energy use and environmental impact, and the technical performance and maintenance needs, there remains significant room for improvement in achieving best practices in the energy efficiency of heritage homes.

Enhancing building resilience is crucial to address the challenges posed by climate change and urbanization. The built environment significantly influences indoor comfort, energy efficiency, and the urban heat island (UHI) effect. The European Directive on Energy Performance of Build-ings highlights the urgent need to reduce energy consumption and im-prove thermal comfort. To this extent, passive solutions offer a sustain-able and cost-effective alternative to active systems.

This study focuses on assessing the thermal resilience of buildings in a Mediterranean urban district with different building configurations un-der both recent and future climate scenarios. This study intends to inte-grate climatic data, material properties, and energy performance metrics into a decision-support tool, helping stakeholders select optimal refur-bishment strategies that enhance resilience, improve energy efficiency, and minimize environmental impact.

To this end, EnergyPlus and City Energy Analyst are compared to model the thermal performance of buildings under various refurbishment sce-narios. The methodology involves: collecting and analyzing site-specific climatic and case-study building performance data; simulating different passive strategies with special reference to the building enve-lope; assessing energy efficiency indicator, alongside thermal comfort.

Retrofitting the widely used prefabricated concrete buildings can reduce energy consumption and improve occupant comfort in winter and during the increasingly frequent summer heat waves caused by climate change.

The goal of this research was to find the optimal retrofit measures for a typical prefabricated concrete building in Hungary based on energy consumption and summer comfort. The building was studied with dynamic simulation, calibrated with real consumption data. Different retrofit alternatives such as thermal insulation, window replacement and shading were investigated. A sensitivity analysis was used to identify the most important factors, followed by optimisation to investigate how the different retrofit options interact with each other, which retrofit methods have the greatest impact on reducing the number of discomfort hours and which factors have the most significant impact on energy consumption. For the optimisation, the genetic algorithm of DesignBuilder was applied.

As a result of the study, the optimal retrofit solution was selected from a number of alternatives and its effectiveness was analysed using future climate models.

Based on the results, recommendations can be made for retrofits that reduce greenhouse gas emissions and improve occupant comfort. In the long term, building modernisation contributes to sustainable development and the fight against climate change.

This study evaluates the energy performance and thermal comfort of a multi-story social housing complex in Budapest’s 8th District, focusing on the energetical and structural challenges of refurbishing aging urban buildings. Utilizing dynamic simulation software (IDA ICE), the research assesses heating and cooling loads, energy consumption patterns, and the potential benefits of targeted refurbishment strategies. Findings reveal that heating demands dominate energy consumption at over 85%, with significant losses attributed to poorly insulated building envelopes and thermal bridges. Simulation results demonstrate that energy-efficient interventions, such as enhanced insulation and upgraded window systems, could reduce heating loads by 50–80%, ensuring compliance with EU energy directives.

The study also addresses the practical complexities of retrofitting buildings with outdated structural designs, emphasizing the integration of passive and active systems for sustainable energy performance. While prioritizing energy optimization, the research acknowledges the importance of occupant comfort, maintaining indoor thermal conditions within acceptable ranges. By providing actionable insights into energy-efficient refurbishment practices, this work contributes to the broader goal of sustainable urban renewal, offering a replicable framework for policymakers, urban planners, and architects working to enhance the energy performance of existing building stock.

The increasing frequency and intensity of heatwaves due to climate change necessitate advanced approaches to enhance the thermal resilience of residential buildings. Long-term monitoring and calibrated dynamic simulations provide critical insights into building performance and adaptation strategies. However, the limited data availability on occupied buildings complicates the calibration process. This research addresses these challenges by integrating on-site monitoring data with 3D dynamic simulation tool to assess current overheating risks and future climate scenarios while evaluating the effectiveness of passive adaptation measures.

In this research, simulations were conducted using data from a prefabricated concrete panel building. A geometric model with 262 zones was developed in DesignBuilder software based on architectural plans and on-site inspections. After defining the boundary conditions, the model was calibrated for one month to match the measured internal temperatures. The calibration process focused on adjusting ventilation rates and internal gains, incorporating actual monitoring schedules for window openings. The performance of the calibrated model was evaluated using statistical indicators such as NMBE and CV(RMSE), ensuring alignment between measured and simulated data.

The calibrated model was used to assess the building's performance under future climate scenarios for Budapest while maintaining the same user operations. Simulations were conducted incorporating IPCC RCP 2.6, 4.5, and 8.5 pathways for 2030, 2050, and 2100. Overheating was assessed using the ODH26 indicator. Results revealed a significant increase in overheating, with values doubling by 2030 (RCP 2.6), tripling by 2050 (RCP 4.5), and increasing sixfold by 2100 (RCP 8.5).

Adaptation strategies were analyzed, including advanced ventilation, shading, upgraded glazing, and wall insulation. Results indicated that individual adaptations have varying levels of effectiveness. Advanced ventilation reduces overheating by up to 43%, but its impact diminishes significantly under future scenarios, with reductions ranging from 9% to 26%, depending on the scenario. Combining strategies, such as ventilation with shading or glazing upgrades, enhanced effectiveness, reducing overheating by up to 59%, highlighting the importance of inclusive solutions. Lastly, the effect of thermal insulation on overheating was critically analyzed, showcasing its dual role as both a mitigation strategy and a potential contributor to overheating when applied without proper shading or ventilation.

The findings underscore that while passive solutions such as ventilation and shading remain effective under current climates, they will likely become insufficient as climate change progresses. Comprehensive and tailored adaptation strategies, combining passive and active measures, are essential for ensuring long-term thermal comfort in residential buildings under future climate conditions.

Changes in weather and climate are increasingly affecting our daily lives. Past experiences and habits, as well as some regulations that are still in place, are undergoing fundamental changes today. In addition to prevent-ing further climate change and mitigating current impacts, there is a grow-ing need to focus on building adaptive capacity. In Hungary, in the long-er term, the seasons are likely to change, with more extreme summers and winters and shorter transition seasons. The factors defined in the cur-rent regulatory framework will become obsolete and may require more frequent review in the future. In addition, mechanical cooling is becom-ing more and more important, in addition to the former heating-centred mechanical systems, and even passive, architectural solutions may gain ground. The main goal is to look at the temperature and weather changes that have had the greatest impact on energy, both in the past and in the foreseeable future.