Passive House and EnerPHit multi-unit residential buildings: A comparative analysis of modelled and measured energy performance post occupancy

ABSTRACT This article presents the first quantitative analysis of the thermal performance of mud brick housing in Classical Greek cities. By integrating 3D architectural modelling with Rhinoceros 3D and the Ladybug and Honeybee environmental simulation toolsets, it introduces a novel methodological framework for studying ancient earthen architecture. Focusing on housing blocks at Olynthos, the study examines how architectural form, material properties, and house location shaped indoor climates. Results demonstrate that mud brick moderated temperature fluctuations, yet specific building forms and locations created perceptible differences in thermal comfort between rooms, storeys and house position within a city block. By moving beyond purely morphological or economic readings of domestic space, this research shows how earthen architecture shaped lived social experience and advances debates on the temporality of life, equality and standards of living in the Classical polis.

This paper explores the use of passive design strategies for indoor thermal comfort in kampungs. A prototype is developed to represent typical kampung houses. Based on literature review and the climate analysis of Jakarta, eight passive design strategies are investigated via building simulations regarding their impact on indoor thermal comfort . The results show that natural ventilation, cool roof, green walls, and cool exterior walls are all effective strategies, each reducing the number of hours not meeting the adaptive thermal comfort requirement per ASHRAE Standard 55 by more than 10%. When integrated into a comprehensive package—combining full-day natural ventilation (≥11 air changes per hour), cool roof, cool exterior walls, wall insulation, and single-pane reflective glazing – passive design can decrease discomfort hours by 57%, from 8035 h in the base case to 3433 h annually. The findings can be used to develop passive house standards aimed at improving living conditions in Indonesia.

This study examines approaches to energy-efficient and sustainable design of residential buildings in various climatic zones of Tajikistan based on the Passive House concept. The analysis of the country’s climatic characteristics and their impact on thermal protection requirements for buildings is presented. Architectural and structural solutions of a Passive House are described, including enhanced insulation of building envelopes, elimination of thermal bridges, optimal orientation and compact form of the building, as well as the use of energy-efficient windows and solar-shading systems. Engineering systems of a Passive House — balanced ventilation with heat recovery and the use of alternative energy sources — and their adaptation to local conditions are also explored. Special attention is given to the use of local construction materials to reduce the carbon footprint and improve the sustainability of building practices. A techno-economic comparative analysis between Passive Houses and conventional buildings Паёми политехникӣ. БАХШИ ТАҲҚИҚОТҲОИ МУҲАНДИСӢ. № 1 (73) 2026 183 shows that Passive Houses can reduce heating energy consumption by 70–90 %, while requiring only a moderate increase in initial investment. Examples of implemented energy-efficient housing projects in Tajikistan and neighboring Central Asian countries are provided. The results of the study demonstrate that the Passive House concept, when adapted to the extreme climatic conditions of Tajikistan, can significantly improve the energy efficiency and sustainability of residential construction, ensuring a comfortable indoor environment with minimal energy consumption.

This paper delves into the critical intersection of sustainable development in terms of the residential building with a particular focus on passive house designs and their environmental impacts. Passive houses are distinguished by their exceptional energy efficiency, relying minimally on active heating and cooling systems, which makes them a leading model in sustainable residential construction. Through this research, this paper aims to shed light on the environmental implications of passive house designs by employing Life Cycle Analysis (LCA) as a key evaluative tool. The primary objective of this study is to conduct a comprehensive Life Cycle Analysis of a single-family passive house, comparing its environmental performance against a more conventional Base model. The analysis specifically targets the stages A1-A3, which focus on materials, and B6-B7, which focus on the operational energy use and water consumption. By concentrating on these crucial stages, this investigation provides a detailed assessment of the long-term environmental benefits and trade-offs associated with passive house construction.

Radon is the most important of all sources of natural radiation, and it belongs to the main air pollutants in closed space. It is necessary to develop awareness of its harmful effects in buildings in order to take appropriate measures to reduce the risk of exposure to it. This study assesses public awareness of radon-related risks in Serbia by analyzing four areas: general public, legislative framework, professional practices, and student knowledge. Data were collected from media sources, legal documents, conferences and scientific publications, and surveys among students of University of Belgrade. Student answers have shown that they are not aware of the danger of radon in buildings: there is a gap between knowledge about radon and about its effects in the interior space. The results also show low presence of this topic in the media and in professional circles in Serbia. This paper is a contribution to the overall efforts to spread awareness in Serbia about the problem of the presence of radon in closed spaces and the health problems it can cause. This is also important in the context of the search for energy-efficient building solutions, where the passive house is emerging as the most sustainable form. It is a relatively new concept in Serbia, so information about the harmful effects of radon in indoor spaces and about the implementation of certain strategies in passive construction for protection against radon is necessary in order to protect the health of the environment and the population.

Traditional and listed housing in Scotland is widely recognized for poor thermal efficiency. Deep energy retrofits are increasingly proposed to reduce energy demand, with Passive House offering an independent standard for high-performance buildings. This study investigates the feasibility of retrofitting a 1960s B-listed dwelling in Scotland to the EnerPHit standard using a case-study approach. A baseline model of the existing building was created using the Passive House Planning Package, and three retrofit strategies were assessed. The results show that the internal wall insulation (IWI) strategy met EnerPHit requirements. However, this approach generated higher CO2 emissions than the external wall insulation (EWI) strategy, which, while performing less well thermally, produced fewer emissions and may be more practical. A third strategy using natural materials performed the poorest. Given the building's listed status, EWI is identified as the most achievable option.

In this paper, we clarify the relationship between storage battery capacity and energy independence, taking into account the relationship between photovoltaic power generation and electricity demand, with the aim of achieving ZEH (100% energy independence) throughout the year in six regions where actual buildings are located.

ABSTRACT Nature has long inspired the intelligent and efficient design of functional materials. However, seamlessly integrating multiple functions from distinct biological origins into a single material platform remains challenging. Here, we present a scalable, bioinspired adhesive patch that monolithically integrates three synergistic functionalities: dry adhesion, thermal insulation, and thermochromism. Each function can be independently tuned through a universal bifacial microstructure and controlled material composition, enabling multifunctional integration without compromising individual performance. The large‐area (∼22 in 2 ) patch simultaneously exhibits robust dry adhesion (∼3.8 N/cm 2 after 100 attachment–detachment cycles), low thermal conductivity (∼0.065 W/m·K), and programmable thermochromic response. When applied to indoor surfaces, it provides passive thermal insulation, real‐time ambient temperature sensing, and self‐adaptive visual transformation, offering both energy savings and interactive feedback. By integrating multiple power‐free functionalities in a single patch, this work lays the foundation for intelligent material systems for sustainable, on‐demand thermal management across diverse applications, including energy‐efficient passive houses.

Passive House Latsia is the first apartment building in Cyprus to be designed according to the Passive House Standard and is set to be certified by both the Hellenic Passive House Institute and the German Passive House Institute [1]. The building comprises 30 apartments with a total area of 2,800 m² and is part of the government’s“Ktizo”initiative for social and affordable housing aimed at young families. Currently under construction, the project is scheduled for completion by the end of 2025. It serves as a prime example that high thermal comfort and ultralow energy demand can be achieved in cost-effective housing. With just a 40 kW photovoltaic system, the building will be energy-neutral—generating as much electricity as it consumes.

Affordability is one of the most important factors in student housing development, especially in rapidly growing cities with increasing property prices. Beyond economic aspects, student housing needs to focus on environmental issues and community integration to create and maintain sustainability in the long run. ReGen Hall illustrates a unique approach to student housing projects aiming to demonstrate the viability of integrating ecological sustainability and affordability while preserving the community fabric. Located in Austin, Texas, the project incorporates advanced modular construction methods, Passive House design principles, and innovative net-zero energy strategies. This 62,000-square-foot residence hall integrates renewable energy systems, including a 320-kW photovoltaic array and rainwater harvesting infrastructure, to significantly reduce operational emissions and water dependency. Life Cycle Analysis (LCA) of the building carried out over a projected lifespan of 100 years reveals a carbon footprint of 2,853 tons of CO2e. This analysis is calculated using verified data from One Click LCA and industry benchmarks to ensure rigorous methods. Economic evaluations show cost reductions through modular construction, bringing total project expenses well below local benchmarks. Moreover, community-focused design elements, such as shared spaces, green courtyards, and a free medical clinic, foster social cohesion while meeting the housing needs of a diverse student population. Employing a quantitative research approach and spatial analysis, this study evaluates the environmental, economic, and social impacts of ReGen Hall. The findings demonstrate that sustainable technologies can effectively balance affordability and environmental stewardship and offer a model for future student housing developments.

THE PURPOSE of the study was to propose a more effective option for heat conservation through the insulation of building envelopes. Calculations were analyzed using PHPP (Passive House Planning Package) software. Research and calculations revealed that insulating building envelopes can significantly reduce energy consumption for heating. The impact of these measures was analyzed on the fuel and energy balance of Mongolia. SIGNIFICANCE. The scientific significance of the study lies in its comprehensive assessment of the impact of insulating building envelopes on reducing heat loss, energy consumption, and CO2 emissions in Mongolia. METHODS. The study utilized analytical and computational methods. PHPP software, which allows for the modeling of energy performance of buildings with different insulation options and envelope thicknesses, was used to assess heat loss and potential energy savings. RESULTS. All existing older buildings belong to energy efficiency class D. To achieve energy efficiency, these buildings must be classified as energy efficient or class A, and all building envelopes must have insulation at least 250 mm thick and a thermal conductivity of 0.04 W/(m∙K). For panel apartment buildings, assuming windows insulated with energy-saving double-glazed windows, the annual consumption is calculated to be 133.8 GWh. The implementation of this measure could save 368.6 GWh of thermal energy and reduce 263.3 thousand tons of CO2, which is in line with the Paris Agreement targets for 2030. For brick apartment buildings, the annual consumption is calculated to be 99.1 GWh. Implementing this measure would save 305.3 GWh of thermal energy and reduce 218.2 thousand tons of CO2. CONCLUSION. Currently, the annual heat consumption of panel buildings is 502.1 GWh (431,700 Gcal), and that of brick buildings is 404.4 GWh (347,700 Gcal) in Ulaanbaatar. This figure accounts for 53 percent of the thermal energy in fuel and energy balance of Mongolia.

ABSTRACT This paper presents a case study conducted in the neighborhood Vallastaden in Linköping, Sweden, where developers built low energy cooperative housing intended to meet the passive house standards. Previous research highlights the need for integrated approaches to understand residents’ thermal comfort and energy use, as some low energy house concepts fail to meet energy performance requirements. The aim of the paper is to contribute to the understanding of cooperative housing and residents’ experiences of thermal comfort in newly built homes in Sweden. Through a detailed case study that included activity diaries, visualizations based on diary data and workshops with residents, we explored residents’ actions to achieve thermal comfort. With concepts from time-geography, we discuss insights regarding residents’ experiences and strategies. Results show that cooperative housing in Vallastaden, while being comfortably warm during winter, suffers from poor design and engineering to protect residents from overheating during hot summer days. Residents choreographed their space-time activities to adjust for the constraints of the designs by elaborate schedules for airing, remodeling their homes or sometimes staying away from the home. Exploring this everyday experience together with visualizations of thermal comfort brings forward new insight into the thermal comfort concerns of residents in cooperative housing.

The increasing demand for rapid, high-return real estate flips has exposed the inefficiencies of traditional renovation methods, which often suffer from extended timelines, fragmented trade coordination, and inadequate integration of modern energy and smart-home technologies. This paper investigates the EcoFlipFrameTM system, a patented modular renovation framework designed for speed flipping, as a case study of how industrialized construction and embedded IoT infrastructure can reduce renovation timeframes by 50–80%, elevate building performance to near– Passive House standards, and enable plug-and-play smart home deployment. The system’s prefabricated panels integrate structural, thermal, mechanical, electrical, and digital layers into unified components that assemble on-site in a matter of days. A comparative analysis with conventional renovations and other modular systems demonstrates the significant ROI gains achieved through compressed schedules, labor reduction, enhanced resale value, and operational energy savings. The findings suggest that EcoFlipFrameTM offers a viable path toward scalable, efficient, and technologically advanced retrofits for investors in the residential housing market.

To support national carbon neutrality goals, enhancing the thermal insulation of building envelopes has emerged as a crucial strategy in reducing building energy consumption. This study conducted a detailed quantitative analysis of energy performance improvements achieved through enhanced insulation levels in four representative non-residential building types: office, accommodation, educational, and sales facilities. Based on four scenarios—Baseline (2019), Insulation Reinforced, Passive House, and Zero Energy Building (ZEB)—EnergyPlus simulations were performed to calculate end-use energy demand and consumption. The results revealed that office buildings achieved the highest improvement, with up to 34.7% energy reduction, while educational and sales facilities showed moderate and limited improvements, respectively. These findings provide quantitative evidence for prioritizing insulation-based policies and differentiated ZEB strategies tailored to each building type. The proposed RB models and scenario-based methodology offer a robust foundation for establishing future ZEB regulations and performance-based energy policies in South Korea. To ensure clarity, the study explicitly referenced verified data sources and field measurements. The IdealLoadsAirSystem used in the simulation assumes 100% system efficiency; thus, the reported outcomes represent building system loads rather than final energy consumption. The ZEB-level scenario analyzed in this study focuses on envelope and lighting improvements only, not on HVAC system optimization.

Abstract The construction industry significantly impacts the earth’s climate and resources, responsible for nearly 50% of raw material extraction. With material consumption expected to rise, transitioning from a ‘Take-Make-Dispose’ approach to a circular system that extends material lifecycles is crucial for achieving the EU’s 2050 climate neutrality targets. This study estimates the recycle and reuse potential of five development plans: (1) repeating the current building structure, (2) renovating to KfW-55 standards, (3) renovating to KfW-55 standards with a densification of two additional timber floors, (4) demolishing and reconstructing to passive house standards in timber frame, and (5) demolishing and reconstructing to passive house standards in massive construction. The analysis is based on representative buildings from a district in Würzburg, categorized into 11 age classes to reflect construction practices and material compositions. Python is employed to assess material cycles and environmental impacts, utilizing standardized building materials and components identified through the CircularGreenSimCity project. The analysis incorporates the Urban Mining Index (UMI) and the Material Circularity Indicator (MCI) to adjust recycling and reuse estimates obtained from the ÖKOBAUDAT database. The findings show that renovation scenarios, according to KfW-55 standards, outperform demolition and reconstruction, as well as the replication of the current building structures in terms of sustainability. These findings offer a decision-support for improving circularity and reducing environmental impact in the construction industry.

A multidimensional assessment of passive container houses: Energy, emissions, and economics

In Pakistan and most other developing nations, the residential building sector is one of the highest energy-consuming domains. The residential sector has the highest share of 50% of final electricity use of the country. Though Energy Conservation Building Codes (ECBC-2023) provide structured energy guidelines, no work has been performed to quantify the actual energy-saving potential of code-compliant retrofits in residential buildings. This study investigates the performance of ECBC-compliant retrofitting strategies for residential buildings under Pakistan’s diverse climatic conditions. The Passive House Planning Package (PHPP), a validated simulation tool, was used to assess energy performance improvements through building envelope interventions such as thermal insulation, solar shading, window glazing, and optimal orientation. Field data were collected from three representative cities, Multan (hot desert), Taxila (humid subtropical), and Quetta (cold semi-arid), to simulate both conventional and energy-efficient building scenarios. The results showed substantial seasonal energy savings in all three climates. During the heating period, energy savings were 48%, 50%, and 60% for Taxila, Multan, and Quetta, respectively. Similarly, energy savings during the cooling season were 44%, 33%, and 16%. Life cycle economic analysis revealed that these retrofits yielded Net Present Values (NPVs) of USD 752 (Taxila), USD 1226 (Multan), and USD 1670 (Quetta) over a 30-year period, with discounted payback periods ranging from 6 to 10 years. Furthermore, a life cycle assessment demonstrated that retrofitted buildings yielded up to 26% reduction in overall carbon emissions, combining both embodied and operational sources. The findings highlight that ECBC-2023 is not only a technically viable solution for energy savings but also financially attractive in residential retrofitting. By incorporating localized climate responsiveness into ECBC-compliant building design, the study provides a practical roadmap for achieving Pakistan’s energy efficiency goals. Additionally, the outcomes serve as a basis for informing policy initiatives, supporting building code adaptation, and raising public awareness of sustainable housing practices.

The article examines global environmental trends that shape the diversification of the construction sector. The relevance of the topic stems from the sector’s transformation under the influence of climate policy, technological innovation, and sustainability-driven market reconfiguration. While construction remains one of the most resource-intensive and carbon-heavy industries globally, its ecological modernization is becoming a key driver of green economic growth, investment flows, and urban transformation. The study identifies four major vectors of diversification: (1) regional diversification, manifested in the uneven geographic distribution of green investments and the varying priorities of sustainable development across countries (e.g., the prevalence of residential eco-projects in the U.S. and China versus commercial ones in the EU); (2) institutional diversification, involving the active participation of non-construction actors—such as tech giants, energy providers, and financial institutions—in shaping green construction markets; (3) technological diversification, reflected in the integration of smart systems, eco-friendly materials, digital design, and zero-energy solutions across different construction phases; (4) investment diversification, driven by the rapid expansion of venture capital in green technologies, mergers and acquisitions, and cross-sectoral financing strategies. Through the lens of green construction, the article highlights the interplay between environmental standards, innovation ecosystems, and macroeconomic dynamics. Particular attention is given to the role of early-stage financing, certification systems (LEED, BREEAM, Passive House), and international trade shifts toward green building materials. The analysis draws upon international reports, market data, and policy initiatives from the EU, U.S., China, and South Korea. The results may serve as a conceptual and empirical basis for further interdisciplinary research, as well as for shaping effective sustainability-oriented policies in the construction industry. The article advocates for treating green construction not only as an ecological necessity but as a strategic economic sector of the post-carbon future.

Filtration systems for particulate matter reduction in outdoor air: a review.