Single-family Buildings Research Articles

The Methodology for Designing Residential Buildings with a Positive Energy Balance—Case Study

The article presents the results of the application of an original methodology for designing residential buildings with a positive energy balance in accordance with the principles of sustainable development. The methodology was verified using a computational example involving the selection of a compromise solution for a single-family residential building with a positive energy balance located in Warsaw, Poland. Three different models of decision-makers’ preferences were created, taking into account selected decision sub-criteria. Three technical solutions were identified, permissible according to the principles and guidelines for designing buildings with a positive energy balance. As a result of the performed calculations, the final order of the analyzed variants was obtained, from the most preferred to the least accepted solution. Variant 2 is definitely the most advantageous solution, being the best in a group of 20 to 26 evaluation sub-criteria—depending on the adopted model of the decision-maker’s preferences. Its ranking index Ri ranged from 0.773 to 0.764, while for the other variants it was much lower and varied from 0.258 to 0.268 for variant 1, and from 0.208 to 0.226 for variant 3. The methodology used for the case study proved to be applicable. The developed methodology facilitates the process of designing residential buildings with a positive energy balance, which is an extremely complex process.

A novel grid-connected solar PV-thermal/wind integrated system for simultaneous electricity and heat generation in single family buildings

The development of novel grid-connected integrated renewable energy systems for sustainable residential buildings is vital. The aim of this paper is to analyze the energy, economic and environmental performance of a novel grid-connected renewable energy system consisting of solar hybrid PV-Thermal collectors, wind turbine and sensible heat storage. The new integrated system serves concurrently hot water and electricity loads to a single-family building located in Laayoune, Morocco. The system adopts a stratified thermal storage and an auxiliary back-up to satisfy continuously the thermal load. Energy interaction between the examined system, load and grid is predicted at regular time intervals of 0.25 h. For a wind capacity of 1.2 kW, PV-T thermal collectors with a total area of 2.84 m2 and a storage tank of 0.3 m3, the system was able to satisfy 43.08% and 64.8% of the electric and heat demand, respectively. Compared to three other power supply scenarios, the economic assessment of the proposed configuration revealed that its Net Present Cost (NPC) is lower by 20.7%, 10.7% and 11.5% compared to grid only, PV-T only and wind only scenarios, respectively. As such, the novel system presents promising development perspectives especially that it allows additionally a reduction of up to 54% in the annual CO2 emissions compared to the conventional energy supply mode relying entirely on the electric grid.

Tightness of Single-Family Buildings Made in Prefabricated Wood Frame Technology

The overall objective of the study is to determine the influence of various factors on the tightness of frame-based buildings. The study presents airtightness tests—Blow Doors Tests of single-family residential buildings made in the prefabricated wood frame technology. Primarily, the impact of selected quantitative and qualitative parameters on the determined quantity n50 was defined. For that purpose, correlation analyses were performed and the statistical hypothesis stating that there is no statistically significant linear relationship between n50 (a multiplication factor of air exchange in the building effected by pressure difference of 50 Pa) and the specified qualitative and quantitative parameters was verified. The hypothesis was verified using the F and χ2 statistics. The studies demonstrated that there are no grounds to reject the research hypothesis. The obtained results formulate a comprehensive conclusion that allows to test the tightness of buildings made in the prefabricated wood frame technology and makes the tightness results independent of many features of the examined building. Ultimately, the tightness results are only dependent on the leak of the examined object. They do not depend on roof structure, wall system, floor area, cubature, number of window openings, porch.

Energy performance criteria for residential buildings: A comparison of Finnish, Norwegian, Swedish, and Russian building codes

Building code are considered to be an effective policy tool to reduce energy use in buildings. In practice, national priorities influence the indicators and criteria adopted in the building codes. Consequently, neighbouring countries with similar climate conditions may use different criteria in their building codes to regulate the energy performance. In this paper, the energy performance criteria and their relative stringency in the latest residential building codes of Finland, Norway, Sweden and Russia are compared. The study is based on energy performance evaluations of one single-family building and one multi-family building, located in the north of Sweden. Both buildings complied with the Norwegian and Russian building code. However, the buildings did not comply with the specific fan power and heat loss criteria in the Finnish building code. Additionally, the single-family building did not comply with the specific primary energy and electric powerdemand criteria in the Swedish building code when heated by an electric heater. The national standard input data were found to have a large influence on the buildings’ compliance with the studied energy use criteria. Policy implications of the results are discussed.

Operational tests of an electrostatic precipitator reducing low dust Indexed by: emission from solid fuels combustion

The article presents the continuation of the research aimed at designing, manufacturing and selecting the operating parameters of the electrostatic precipitator for household applications. The tests were carried out in the laboratory and real conditions. The object of the research was a pre-production prototype of the electrostatic precipitator installed in the flue gas duct of a single-family building. The source of exhaust gases was a coal-fired, low-temperature water heating boiler with a nominal power of 21 kW (old generation boiler-year of production: 2007). The obtained results showed that the adopted design of the electrostatic precipitator enables the reduction of dust emissions generated in the combustion of solid fuels in households at relatively low operating costs.

The technology that meets modern human needs – criteria of assessment of smart home system

The article is a summary of the research conducted for educational purposes with the participation of students from the University of Technology in Lublin in Poland, on the design and use of facilities created as smart home (SH). The increasing availability of smart building equipment systems is associated with their widespread use and reasonable price. New technologies, which are the result of scientific and technological progress, make it possible to use the devices to raise the standard of habitation and use of buildings. The creation of SH facilities nowadays is not only limited to single-family buildings. More and more often we observe smart multi-family and public utility buildings. At the same time, we are aware of the design of energy self-sufficient facilities, which allow us the freedom to build in undeveloped areas.

Life Cycle Assessment as a Major Support Tool within Multi-Criteria Design Process of Single Dwellings Located in Poland

Life cycle assessment is an environmental method which estimates either a process or a building material within the cradle-to-grave cycle. Presently, it is one of a few tools that include all factors which may influence the environment. The authors used this tool to prove effects connected with potential efficient energy levels and a reduction in CO2 emissions within a building’s life cycle. For the purpose of our analyses, several types of single-family building were chosen and they were subjected to analysis in the fixed location of Warsaw. The research scope included a numerical analysis of the buildings concerning the level of embodied energies and the emission of greenhouse gases. The performed analysis proved that, within a 50-year cycle, the difference between the embodied energy from the best and worst building choices can amount to 14.87%, whereas a reduction in embodied carbon emissions can reach 20.65%. Each change in the building’s form and the type of building materials used, regardless of the usable area, influence the environmental impact. Therefore, this paper concludes that LCA, as a management tool, should be used cyclically as part of each phase of the design process. A multi-criteria method for selecting architectural solutions was proposed which considered minimum cumulative primary energy, minimum cumulative carbon emission and minimum cost of constructing a building.

Strategy for achieving long-term energy efficiency of European single-family buildings through passive climate adaptation

The presented study aims to clarify the implications of passive design measures on heating and cooling energy use of single-family residential buildings under European representative climates. In order to address this matter, different values of thermal transmittance (opaque and transparent), window to floor ratio, window distribution, shape factor, diurnal heat storage capacity, external opaque surface solar absorptivity and natural ventilation cooling rates were combined in 496,800 building energy models, which were simulated at eight locations. Because buildings are in use for many decades, the energy use simulations were made considering the projected climate change up to the end of the 21st century. The results delivered a set of the most effective passive design measures for achieving low energy use in buildings regarding climate type and period. A lower window to floor ratio was identified as the most universally applicable design measure to counterbalance the projected effect of a warming climate. In contrast, other measures vary according to climate type and studied period. Furthermore, it was concluded that it is difficult to neutralise the projected climate change effects on buildings' energy use, even when applying the best performing combination of passive design measures. However, reasonably low energy use can still be assured solely by passive building design, especially in oceanic, warm, and some temperate climate locations. Therefore, the identified trends in energy use and passive design measures represent the foundation for strategies and guidelines aimed at future-proof energy-efficient buildings.

The influence of internal installation solutions in single-family housing on the "EP" factor in the light of the new requirements of WT 2021

The first part of the article presents the upcoming changes in the regulations regarding energy consumption by single-family housing. Current and forthcoming requirements in 2021 for building insulation and maximum EP primary energy demand factor were indicated. The second part of the paper presents the results of research aimed at determining what type of heat source for heating purposes and the type of ventilation will be able to meet the latest requirements. The analysis was based on the determination and comparison of the EP factor in the considered single-family building for selected heating variants assuming two different types of ventilation: gravitational and mechanical supply-exhaust with heat recovery system. Based on the results obtained, an attempt was made to determine the tendency of changes in the design of single-family buildings in terms of choosing the type of heating and ventilation.

Analyses of the Life Cycles and Social Costs of CO2 Emissions of Single-Family Residential Buildings: A Case Study in Poland

Comprehensive environmental impact assessments of buildings and construction as a whole consider the preparation of construction and finishing materials, their transportation, the process of erecting buildings, long-term operations—including the consumption of electricity, water, and fuels—and the management of the waste generated during the demolition of facilities. In terms of the above-mentioned elements, the most negative environmental impact on a building’s life cycle is in its exploitation stage. In order to reduce this impact, modern sustainable construction uses renewable energy sources. In the area of the Polish building market, analyses of CO2 emissions, the application of LCAs for building materials, and assessments of the social impacts of modern buildings are still very limited. The aim of this study is to evaluate the environmental life cycles and social costs of the CO2 emissions of single-family residential buildings, in which four different systems providing energy (heat and electricity) from renewable and nonrenewable sources are used. In this research, it was found that the annual CO2 emissions per square meter of building surface area in the analyzed objects were in the range of 30 to 176 kg CO2. The greatest contributor to the environmental effects was energy consumption (58% to 90%). The CO2 analysis conducted showed that facilities that use a heat pump are characterized by an environmental effect that is six times lower than that of facilities that are powered by coal combustion and electricity from the network. Similarly, the social costs associated with CO2 emissions were significantly lower in the case of the use of renewable energy sources.

Optimization of Modernization of a Single-Family Building in Poland Including Thermal Comfort

The impact of thermal comfort demand on the renovation process was carried out on an optimization basis for the thermo-modernization process of an exemplary single-family home located in Warsaw. The verified TRNSYS simulation program was used to generate a set of variants of building modernization solutions. This variants set was used afterwards as a database for optimization. The analysis performed includes the internal air temperature, indicators of thermal comfort (PPD), and annual energy demand for heating and cooling, and investment costs of modernization building. The results indicated the importance of analyzing various variants of building modernization solutions. Performing modernization without analyzing its effects can have positive as well as negative consequences, e.g., achieving a significant reduction in the primary energy demands at the expense of the deteriorated thermal comfort of users. It was shown that separate analysis of indicators leads to completely different solutions and should not be recommended during modernization of single-family buildings.

Hybrid Hydrogen Home Storage for Decentralized Energy Autonomy

As the share of distributed renewable power generation increases, high electricity prices and low feed-in tariff rates encourage the generation of electricity for personal use. In the building sector, this has led to growing interest in energy self-sufficient buildings that feature battery and hydrogen storage capacities. In this study, we compare potential technology pathways for residential energy storage in terms of their economic performance by means of a temporal optimization model of the fully self-sufficient energy system of a single-family building, taking into account its residential occupancy patterns and thermal equipment. We show for the first time how heat integration with reversible solid oxide cells (rSOCs) and liquid organic hydrogen carriers (LOHCs) in high-efficiency, single-family buildings could, by 2030, enable the self-sufficient supply of electricity and heat at a yearly premium of 52% against electricity supplied by the grid. Compared to lithium-ion battery systems, the total annualized cost of a self-sufficient energy supply can be reduced by 80% through the thermal integration of LOHC reactors and rSOC systems.

Thermal Modernization Cost and the Potential Ecological Effect—Scenario Analysis for Thermal Modernization in Southern Poland

Air pollution is one of the important environmental problems in Poland. The main cause of its occurrence is emissions associated with individual heating of buildings. The reduction of the primary energy demand in a building is influenced by its proper thermal modernization, including in particular insulating. In view of the above, this article presents the results of studies on the possible environmental benefits of thermal modernization of single-family houses for the area of Southern Poland. The analysis was limited to determining the impact of measures to reduce air pollution emissions by insulating the building envelope of single-family houses. The research was conducted for two voivodeships: Śląskie and Małopolskie. Its aim is to identify the financial costs and achievable ecological effects of the thermal modernization of single-family buildings. The geographical selection of the research area was based on the fact that it covers the most polluted region in Poland. This region is characterized by many features that influence poor air quality. Among these features, the most important are: diversified building structure, a diverse topography, and very high population density. To limit multiple variables, we have selected a scenario method that has already been used in similar research. Four scenarios were established to show the relationship between the value of emission reductions and the level of funding for thermal modernization. The analysis allows a comparison of the effectiveness of individual variants and the transposition of their results into the possibilities of action in the region. This research will help to supplement the knowledge of the impact of insulating building envelopes on reducing pollutant emissions by reducing the energy demand of a building. They also identify a possible link between the level of this reduction and the grant amount for thermal modernization. As a result, it was found that a high share of external funding—stimulating the tendency of the inhabitants of the analyzed voivodeships to effective thermal modernization, and thus reducing the buildings’ energy consumption—has a significant impact on the improvement of air quality.

Análise técnico-econômica de fundação superficial tipo radier para uma residência unifamiliar

A fundação é um dos elementos estruturais mais importantes para uma edificação, ela é responsável por transferir para uma camada resistente do solo, todas cargas da edificação. As fundações podem ser divididas entre superficiais e profundas. O radier é um tipo de fundação superficial que se trata de uma laje de concreto que distribui uniformemente as cargas da edificação para o terreno. O objetivo deste artigo é, através de um estudo de caso de uma edificação residencial unifamiliar, comparar técnicas construtivas da fundação tipo radier, em relação à sapata isolada, por meio de uma análise técnico‑econômica entre os dois tipos de fundações superficiais, a fim de definir aquele que apresenta melhor viabilidade construtiva. Para isso, foi utilizado um projeto já dimensionado em sapatas, e, com os mesmos dados, realizou-se um dimensionamento estrutural do radier pelo software Eberick. Mediante aos resultados, foram elaboradas planilhas orçamentárias com valores de referências baseados na tabela regional da SINAPI e cronogramas físicos. Para isso, considerou-se a mesma equipe e jornada de trabalho para ambos os métodos. De acordo com os resultados obtidos, em relação ao custo e prazo, a sapata é mais onerosa e morosa que o radier. Sendo assim, conclui-se um excelente desempenho do radier em relação à sapata, pois quando bem dimensionado, poderá proporcionar melhor viabilidade técnico-econômica para a fundação, que é um dos elementos estruturais mais importantes do edifício. Ressalta-se que esta análise está restrita a este estudo de caso, porém, os resultados obtidos são corroborados por outras literaturas.

Italian prototype building models for urban scale building performance simulation

Urban building energy modeling (UBEM) seeks to evaluate strategies to optimize building energy use at urban scale to support a city's building energy goals. Prototype building models are usually developed to represent typical urban building characteristics of a specific use type, construction year, and climate zone, as detailed characteristics of individual buildings at urban scale are difficult to obtain. This study investigated the Italian building stock, developing 46 building prototypes, based on construction year, for residential and office buildings. The study included 16 single-family buildings, 16 multi-family buildings, and 14 office buildings. Building envelope properties and heating, ventilation, and air conditioning system characteristics were defined according to existing building energy codes and standards for climatic zone E, which covers about half the Italian municipalities. Novel contributions of this study include (1) detailed specifications of prototype building energy models for Italian residential and office buildings that can be adopted by UBEM tools, and (2) a dataset in GeoJSON format of Italian urban buildings compiled from diverse data sources and national standards. The developed prototype building specifications, the building dataset, and the workflow can be applied to create other building prototypes and to support Italian national building energy efficiency and environmental goals.

Potential and Scenarios of Variants of Thermo-Modernization of Single-Family Houses: An Example of the Lubuskie Voivodeship

The excessive air pollution in the Lubuskie Voivodeship and throughout Poland is a very serious problem. One of the main causes of poor air quality is low emission, which arises at a short distance from the ground (up to 40 m). The real reduction of low emission requires a series of measures. The most important of them, include replacement of non-ecological boilers heating single-family buildings, improvement of thermal insulation of outer building walls, development of public transport, limiting the movement of old, non-ecological cars, conducting extensive educational activities, economic support for the poorest families in pro-ecological activities, and development of district heating in urban areas. The issue of thermal modernization is also important from the point of view of ensuring an appropriate level of energy security in the social dimension. The article presents a scenario analysis of activities aimed at reducing low emission through economic support for thermal modernization of single-family houses in the Lubuskie Voivodeship in Poland. The results of the conducted research prove that it is possible to carry out thermal modernization of over 12% of all single-family buildings in the Lubuskie voivodeship, assuming that the co-financing would amount to 60% of the costs of such an investment. The analyses carried out in the article are closely related to low carbon development, and a significant part of emission of harmful substances into the air comes from heating single-family buildings in urban and rural areas.

Factors affecting the deep renovation of a single-family building – a case study

The Energy Performance of Buildings Directive (EPBD) of the EU states that Each Member State shall establish a long-term renovation strategy to support the renovation of building stock into a highly energy efficient and decarbonised building stock by 2050. The motive for the study was the dissatisfaction of inhabitants of a single-family building about the heating costs and thermal discomfort. In this study both the emotional and resource efficiency aspects were considered. The structures and technical systems of the studied small dwelling are typical of representing single-family buildings of the Estonian building stock. The initial purpose was to improve the energy efficiency of a building while preserving the existing load bearing structures as much as possible. The research questions were: 1) what the situation before the renovation was, 2) what solutions can be used, 3) making decisions, whether to renovate or demolish. Calculations were carried out – the thermal transmittance of the envelope structures was calculated based on the construction information, and the linear thermal transmittance of geometrical thermal bridges was calculated by using the software Therm. Field tests performed - the thermography and the air leakage of the building was found by standard blower-door test. Specific air leakage rate qE50=11.1 m3/(hm2) was estimated. A renovation solution was offered considering the need for extra insulation and airtightness. The dwelling energy performance indicator was reduced from the existing 279 kWh/(m2y) to 136 kWh/(m2y). For significant energy efficiency improvement deep renovation measures must be used and the question was whether it is rational. Before making the final decision, several aspects have to be considered: 1) emotional – the demolition or renovation of somebody’s home, 2) environmental aspects and resource-efficiency – the possibilities of the reuse of materials.

Analysis of the Impact of Self-Isolation of Residents during a Pandemic on Energy Demand and Indoor Air Quality in a Single-Family Building

This work presents the results of analysis of the final energy demand (Qk) for a single-family house in a pandemic situation and accompanying self-isolation of residents. It was assumed that the object of study is located in Bialystok (Poland). This analysis covers the impact of various factors such as specific periods of the active pandemic phase, the length of the inhabitants’ self-isolation period, the number of residents at home, and the type of energy source used in the building. Based on the results of computational experiments, a deterministic mathematical model of the relationship between these variables was developed, and the effects of the selected factors on the final energy demand were analyzed for the typical meteorological year (TMY) weather data. It turned out that the change in the length of the self-isolation period from 0 to 31 days caused an increase of Qk by about 6.5% for the analyzed building. When the number of inhabitants changed from 1 to 4, Qk increased by 34.7%. A change from 4 to 7 people causes an additional 26.7% increase in Qk. It was found that the structure of energy demand for this building operation during the period of inhabitants’ self-isolation also changed. With the increase in the length of the self-isolation period from 0 to 31 days, the electricity demand (Eel) increases by about 40–42%, while the demand for energy related to fuel consumption (Qg) decreases by about 7–10%. The article also presents an analysis of the impact of residents’ self-isolation on indoor air quality (IAQ) and thermal comfort. The simulation results showed that the use of variable air volume ventilation allows the CO2 concentration to be kept significantly below the limit value.

Analysis of Thermal Comfort in a Single-Family House in Poland

Abstract The article presents test research on thermal sensations, thermal preferences, as well as general thermal sensations in a single-family building. Graphs were drawn to determine the frequency of answers chosen by the respondents and the relationship between temperature and thermal sensations, as well as the influence of relative humidity on thermal sensations. A comparison was also made between the average thermal sensation vote and the PMV index, which determines the ‘predicted mean vote’ - estimated by the Fanger model. The aim of the study was to compare the actual feelings of the respondents with standard guidelines. As a result of this analysis it was found that the thermal sensations of the respondents do not comply with the adopted model included in the standard.

Thermomodernization of a Residential Building to NZEB Level

Directive (EU) 2018/844 of the European Parliament and of the Council of 30 May 2018 amending Directive 2010/31/EU on the energy performance of buildings and Directive 2012/27/EU on energy efficiency introduces a zero-energy building standard, for which the energy balance per year is zero, i.e. the amount of energy obtained from renewable sources is equal to the annual demand. Each Member State shall establish a long-term renovation strategy to support the renovation of the national stock of residential and non-residential buildings, both public and private, into a highly energy efficient and decarbonised building stock by 2050, facilitating the cost-effective transformation of existing buildings into nearly zero-energy buildings. To achieve energy consumption at an appropriately low level in an existing building, you must adjust the heat transfer coefficients of the building envelope and the demand for primary energy to the requirements of the Technical Conditions for year 2021. Renewable energy sources, primarily from the sun, will also play a key role. A computational example of a single-family building shows which partitions are best modernized, what thickness of thermal insulation materials should be used to properly reduce heat transfer coefficients, and which installation systems to use to reduce the potential energy index (EP). It is also depicted as to how much the demand for usable energy in the building will decrease. This article aims to show residents of single-family buildings what steps should be taken to reduce energy consumption and thus - operating costs in an existing building to a minimum.