Social Dwellings Research Articles

Energy demand and air quality in social housing buildings: A novel critical review

Social housing buildings, throughout Europe, represent a consistent share of the existing building stock. Due to the increasing levels of urbanization, the social housing population in the cities has risen and, after the economic crisis following the subprime mortgage crisis and the pandemic, low-income families as well. The greatest part of social dwellings, those built in the previous century, is usually sub-standard from an energy and environmental point of view. This study reviews the existing literature documenting indoor environmental conditions and energy refurbishment interventions or programs to improve the energy efficiency of existing social buildings. By considering the high risk of energy poverty in social contexts, and the socio-economic conditions of tenants, the economic implications deriving from the energy retrofit were also evidenced. Relevant papers published between 2010 and 2024 were reviewed and were divided according to the reference scale, namely the building or the district scale. The review shows the need to improve the energy performances of social dwellings, both to reduce their energy demand and to improve the indoor microclimatic conditions and quality of life of tenants. Through a critical literature review approach, this study provides a contribution to the in-depth understanding of the role of social housing in the contemporary context, providing meaningful insights for formulating more effective and inclusive housing policies for the next future.

Adaptive Comfort Potential in Different Climate Zones of Ecuador Considering Global Warming

Ecuador is a country with several climate zones. However, their behaviour is similar throughout the year, with no peaks of extreme temperatures in the various seasons. This paper is a first approach to study the adaptive comfort behaviour in several areas and populations of the country. Considering the ASHRAE 55-2020 model, energy simulation programmes are applied not just to the current climate scenario but also to the climate change scenarios of 2050 and 2100. The results of locations are analysed and compared to determine their performance. Thanks to their climate characteristics, adaptive comfort models could be applied as a passive strategy, using natural ventilation for building indoor comfort improvement, particularly social dwellings. According to previous studies, some prototypes have not considered the climate determinants in each region. Given the geographic situation of the study areas, the adaptive comfort model could be applied in all cases. Percentages of application of natural ventilation and heating and cooling degree hours have similar behaviours according to the climatic region, with a variation greater than 30% among them.

Social Housing - A Key Part of Past and Pandemic Impacts

This Social housing represents a crucial facet of social welfare policy and affordable housing provision, constituting over 28 million residences, accounting for approximately 6% of the total housing inventory in OECD and non-OECD EU nations. Considerable variations exist among countries regarding the definition, scale, extent, target demographic, and provider types within the realm of social housing. Although social mixing remains a primary goal in many countries' social housing sectors, there's a growing concentration of lower- income and vulnerable occupants, leading to a diminished diversity of income levels. This trend poses challenges to the economic viability of the sector, fostering an increased spatial clustering of poverty and disadvantage. The size of the social housing sector has dwindled in recent years in nearly all countries with available data, except for six, while the absolute count of social housing units has declined in just four countries with available data. This decline can be attributed, in part, to reduced public investment in housing stock. The pandemic has significantly disrupted construction, rendering it challenging for numerous households to afford shelter and adversely impacting the housing sector. Many countries have initiated substantial revitalization projects to enhance the quality of social dwellings and their surrounding neighborhoods, aiming to address persistent challenges associated with social housing, such as segregation. Policymakers must ensure that renovation efforts do not displace low-income households. Key Words: Social housing, OECD, crisis, response, Finance, Pandemic.

Holistic analysis to reduce energy poverty in social dwellings in southern Spain considering envelope, systems, operational pattern, and income levels

Energy renovations carried out in energy poor households should consider a holistic view in the short-, mid- and long-term, especially in warm areas such as Andalusia, in the south of Spain. This study addresses the existing knowledge gap on technological and economic interactions in the energy poverty of family units in warm areas of Spain. To do this, the study performs a parametric analysis. In this parametric analysis, a dataset of 36,230,400 instances was developed considering envelope, HVAC systems, an operational pattern (based on static and adaptive thermal comfort models), and family units’ income levels. Likewise, the energy poverty ratio was compared based on the high share of energy expenditure in income (2 M). The results showed that improving envelope and establishing adaptive operational patterns did not effectively reduce energy poverty cases in low-income families in the south of Spain. However, these strategies were appropriate in family units with greater incomes to remove energy poverty cases, regardless of the low reduction in energy consumption by improving the envelope. This study is a starting point to combine social aids, energy improvements and rational energy use through adaptive operational patterns.

Management tool of highly efficient social housing to provide healthy indoor conditions and fight energy poverty

This research work presents and analyses the monitoring results of a 42 social dwellings building block during two year (2021 and 2022) showing indoor environmental conditions and energy consumption (DHW and heating), considering not only the energy consumption of the dwellings, but also the heat production in a centralized biomass boiler, and thus, the distribution energy losses. The building has been constructed under Passivhaus standard, so the paper studies the gap between expected and real performance, and highlights the importance of user behavior in the final results, showing the savings potential with the change in the usage of the heating systems.

Sustainable strategies to preserve tangible and intangible values in social housing rehabilitation: an Italian case study.


 
 
 The European social housing stock, built since the early post-war period, now needs major energy, structural and functional upgrading. The owners, almost always public bodies, are therefore called upon to adapt these buildings to the new regulations issued by the European Community. To reduce the costs of intervention, the preferred solution is that of a complete demolition and a subsequent reconstruction by using newly supplied materials, without considering the non-sustainability and social fallout of this choice. The contribution, starting from the hypothesis that more sustainable building rehabilitation interventions are possible, analyses which social and material supply aspects must be considered, and which design strategies can be applied to achieve the objective. First, the characteristics of social buildings in their historical evolution are summarized to understand their value in a broader non-economic sense. Subsequently, the requirements for a sustainable renovation of the existing social dwellings are analysed, and three, out of many other, design strategies are proposed. A case study is then presented and the application of the three strategies done through three Master thesis works is described. In conclusion, the results of the application of the strategies to the case study is analysed to assess whether it is possible to intervene on existing social housing complexes to achieve better results with a more sustainability-oriented perspective.
 
 

Development of a Python-based algorithm for adaptive thermal comfort: Theoretical formulation and application cases

Adaptive thermal comfort has gained momentum within the scientific community as a cost effective and affordable way of maintaining acceptable levels of comfort in dwellings while abating energy expenditure. At the moment two international standards, namely the European EN16798-1 and the American ASHRAE55-2010 shape the understanding of adaptive comfort around the world. However, in recent years concerns have raised about whether they can accurately represent comfort conditions considering the cultural and societal background of different countries, and whether adaptive thermal comfort will be still feasible in future scenarios of climate change. Considering these challenges, this study presents an algorithm which can model different adaptive comfort models; additionally, it can be implemented into energy simulation engines and therefore used to predict energy consumption under different climates, building typologies, and dynamic comfort conditions. This contribution presents the development of the aforementioned algorithm, called ACCIS (Adaptive-Comfort-Control-Implementation Script), originally written in EnergyPlus Runtime Language (ERL) and later nested in a Python package called ACCIM (Adaptive-Comfort-Control-Implemented Model)”, its main characteristics, and also the implementation into two cases studies: The thermal comfort in social dwellings in Spain and Japan considering present and future climate change scenarios namely Representative Concentration Pathways (RCP) 2.6, 4.5 and 8.5 for years 2050, 2080 and 2100. The results show that the predicted energy consumption of low-income families is strongly influenced by the adaptive comfort model chosen to model their thermal routine and suggest that international standards should be put under revision to consider the local particularities of dwellers in subsidized housing projects. The results of this research can be useful to devise public policies aimed at abating energy cost for low-income dwellers that benefit from social housing programs, particularly in the light of the increment of energy costs for heating and cooling associated with climate change..

Ground source heat pump driven by reciprocating engine firing biomethane from wastewater treatment plant sludge in a cogeneration for district heating and cooling. A case study in Spain

Wastewater treatment plants are a key facility in municipalities to reach the required water quality before returning to the environment. Their energy consumption constitutes the most critical cost in their operation, although sludge produced in the treatment can be fed into an anaerobic digester to produce biogas. Such biogas is usually burnt into a cogeneration reciprocating engine that produces power injected into the grid and heat to maintain the required temperature in the digester. This energy recovery technique also avoids direct methane emissions from the biogas to the atmosphere. An alternative energy recovery of the sludge is proposed in this paper, seeking to cover both the winter and summer thermal demands of the municipality whose wastewater is treated by the plant.A district heating and cooling network is assumed to be available in the municipality, whose demand will be met (total or partially) by the proposed system. The biogas production has been assessed from a large number of wastewater treatment plants in Spain. This fuel will be upgraded to biomethane to inject eventual surplus generation into the natural gas grid. The hourly thermal demand is estimated from a self-elaboration expansion of annual expressions given in Spanish regulations. A high insulation level in the dwellings of the municipality is assumed to reach the maximum thermal demand coverage level. Underfloor heating and cooling is used as final air conditioning system. The conversion is carried out by supplying the biomethane to a cogeneration reciprocating engine, whose power output drives a ground source heat pump and its recovered heat is used for the thermal conditioning of the biogas digester as well as for heating in winter.The results show that for a 50,000 inhabitants treatment plant, the thermal demand coverage percentage ranges from 28 % to 51 % and the levelized cost of heating and cooling from 38 to 65 €/MWhth. Generally, the lowest cost is reached in zones with an intermediate coverage percentage. Even with high insulation dwellings and high-efficiency systems, the thermal demand coverage percentage is low. This suggests that biomethane production from all the entire municipality can be devoted to meet a selected district's complete demand, built with high standards. This district might be focused on social dwellings.

Building Assessment and Statistical Characterisation of the Mediterranean Social Housing Stock in Southern Spain

Given that the existing residential buildings are expected to become a huge part of the future stock due to their low replacement rate, retrofitting plans are crucial to meet 2030 and 2050 energy efficiency targets. Notwithstanding, an extensive assessment of the current energy and thermal performance of the stock must be conducted prior to the proposal of energy saving measures in order to properly tackle the retrofit process. Thus, the analysis and characterisation of the existing buildings under real variability conditions through statistical techniques is key to provide useful information at the stock level, instead of the most commonly single-building level approach. In the presented study, a statistical analysis on the most predominant variability ranges of the social housing stock of southern Spain (Andalusia) is carried out. Efforts are focused on the building characterisation of the linear block typology. To do so, an extensive database, which contains information on slightly under 39,500 social dwellings, is analysed. The conclusions reported in this study may be implemented into the construction of real case building archetypes through bottom-up building stock modelling techniques with the objective of assessing the real energy and thermal performance of the existing stock, providing useful information for public stakeholders.

Climate change mitigation: thermal comfort improvement in Mediterranean social dwellings through dynamic test cells modelling

Global warming will lead to adverse consequences for human health and well-being. This research ought to determine whether passive low-cost strategies freely controlled by users (ventilation strategies, solar shadings or window operation) could be applied in low-income dwellings to meet acceptable thermal comfort to retrofit the Mediterranean social housing stock of southern Spain towards climate change. On-site measurements registered in some test cells (controlled environment with no users’ influence) were used to calibrate dynamic energy simulation models. The impact of several future periods, climate zones of southern Spain and orientations on thermal comfort was assessed. The results show that climate change triggers a more significant increase in outdoor temperatures in summer than in winter. Should ventilation be kept to minimum and blinds opened during daytime in winter, higher comfort would be achieved, with great differences between orientations and south reporting the best results. The higher the outdoor temperatures due to climate change, the higher the percentage of comfort hours (i.e. 23–68% in the present and 50–75% in 2080). In summer, natural night ventilation and blinds closed during daytime lead to the best comfort result, with negligible temperature differences between orientations. Future climate change scenarios worsen the percentage of comfort hours (i.e. 96–100% in the present, while up to 17% in 2080). Mechanical ventilation and blind aperture schedules were found to have the highest influence on overheating discomfort. Likewise, mechanical and natural ventilation schedules had the highest impact on undercooling discomfort.

Mitigation of climate change in Mediterranean existing social dwellings through numerical optimization of building stock models

Retrofitting the existing building stock is widely accepted as a crucial factor to reaching 2030 and 2050 climate and energy targets, given that the building sector is among the top three most dominant energy consumers. This paper presents a bottom-up study which uses calibrated and parameterized energy stock models (building archetypes), while also incorporating building stock information from a large database. The thermal performance of the existing social housing stock of southern Spain is assessed through dynamic simulation under present and future climate change scenarios. Subsequently, several passive and low-cost operation-related strategies are numerically optimized through genetic algorithms to determine the best retrofit solutions, taking into consideration global warming scenarios. A multi-objective decision analysis is carried out by optimizing annual overheating hours (%), annual undercooling hours (%), and investment costs (€/m2). Among the conclusions reported, it is important to note the feasibility of implementing low-cost retrofit strategies considering investment costs of up to around 200 €/m2, which would lead to average annual overheating and undercooling hours below 55 % and 45 %, respectively. However, retrofit solutions exclusively based on passive and low-cost operation measures were proven to be significantly limited to improve thermal comfort results in the social stock.

Coating mortars with improved physical properties, economic cost, and carbon footprint

In recent years there has been renewed interest in innovative solutions for coating mortars. Previous research has clarified the importance of substituting a percentage of cement by other binders, and thus focused on a good balance between structural and thermal properties. However, the effect on the economic cost and the carbon footprint is yet to be fully understood. In this context, the present study aimed at investigating the role of hydraulic lime as a partial substitute for cement and expanded perlite in the structural and thermal properties of mortars while considering the economic cost and the carbon footprint as fundamental variables. We employed a combination of laboratory tests and theoretical calculations to clarify the optimal balance between all considered variables. The findings showed that thermal conductivity can be reduced up to 87.25% and density up to 78.94% if compared with a standard mortar; on the contrary, mechanical properties are compromised yet sufficient for rendering purposes. The final product is affordable, and its carbon footprint is remarkably lower than other alternatives. We concluded that these mortars can deliver optimal properties for rendering purposes, except for the mechanical resistance, which demands further research. In turn, our findings provide evidence for devising feasible options to maintain or repair buildings on a constrained budget, as in the case of social dwellings.

Using adaptive strategies of natural ventilation with tolerances applied to the upper limit to improve social dwellings’ thermal comfort in current and future scenarios

Summer weather conditions in Spain generate many thermal discomfort hours. Consequently, it is difficult for low-income family units to ensure adequate conditions inside dwellings. Natural ventilation could improve the thermal comfort conditions of these users. However, the number of thermal comfort hours could be limited in summer. This study analyses the possibility of improving users’ thermal comfort by applying tolerances to the upper limit of adaptive thermal comfort models. The study is conducted in 10 Spanish cities in the current scenario and in a climate change scenario. The tolerances were those considered by the adaptive standards: 1.2 °C, 1.8 °C and 2.2 °C. The results showed that the use of the upper limit without tolerances could imply a low number of thermal comfort hours in some cities and that the use of the tolerances would improve thermal comfort conditions. The estimated climatic evolution throughout the 21st century could limit the use of natural ventilation even with tolerances in the warmer regions, while in regions with less severity in summer natural ventilation would be an appropriate measure.

Can big data increase our knowledge of local rental markets? A dataset on the rental sector in France.

Social Scientists and policy makers need precise data on market rents. Yet, while housing prices are systematically recorded, few accurate data sets on rents are available. In this paper, we present a new data set describing local rental markets in France based on online ads collected through to webscraping. Comparison with alternate sources reveals that online ads provide a non biased picture of rental markets and allow coverage of the whole territory. We then estimate hedonic models for prices and rents and document the spatial variations in rent-price ratios. We show that rents do not increase as much as prices in the tightest housing markets. We use our dataset to estimate the market rent of each transaction and of social dwellings. In the latter case,this allows us to estimate the in-kind benefit received by social tenants which is mainly driven by the level of private rent in their municipality.

Potential of Energy Savings in the Public Housing Stock of Comunitat Valenciana Region by Applying the MedZEB Cost-Optimal Methodology

Improving energy efficiency in buildings has a key role to play in achieving the ambitious goal of EU-wide climate neutrality by 2050, set out in the European Green Deal. This paper describes a cost-optimal analysis of residential buildings of Valencian Community, Spain. Thus, an assessment of the contribution of total primary energy savings per year (MW/h) of the social dwellings managed by EVha, Entitat Valenciana d’Habitatge i Sòl (eng. Valencian entity for dwelling and ground) towards the national contribution is presented in this paper. To assess it, the MedZEB cost-optimal methodology has been applied to optimise the performance of the building’s envelope. This means that Optimal Renovation Strategies through Life-Cycle Analysis have been applied to obtain the Packages of Optimal Solutions of the different reference buildings in a reference climate. First, the renovation scenario with 100% of the building stock being renovated has been calculated. Then, the renovation scenario of 1%, being the current European rate of renovation and, finally the renovation scenario of 2%, given that the objective of the Renovation Wave is to at least double the annual energy renovation rate of residential and non-residential buildings by 2030 and to foster deep energy renovations.

Applying the mixed-mode with an adaptive approach to reduce the energy poverty in social dwellings: The case of Spain

Fuel poverty is a pressing issue in several European countries, and Spain is no exception. Traditionally, it has been associated with cold conditions, but recent studies in the field have stressed its prevalence in warm countries too, during summer. Further, forecasts of climate change for these territories predict more severe summers. This envisages a scenario where low-income families might suffer from fuel poverty due to their inability to afford the energy bill to cool their homes, for tackling which the European Union and its member states are devising strategies. Adaptive comfort models have emerged as a sustainable and resilient approach in this regard. This study aims at clarifying how a change in the behavioural patterns of users, following the adaptive model might reduce the incidence of fuel poverty, compared to the static model based solely on active cooling. For this purpose, a common typology of social dwelling has been simulated in 10 cities representative of the diverse climates of Spain; both the current and future climate change scenarios have been considered. Results indicate that the mixed-mode is effective in alleviating fuel poverty not only in the present scenario, but also in 2050 and 2100, except for the most underprivileged households earning less than 500 € per month. The outcomes of this study will be of use to policy makers, designers, and stakeholders in targeting families in need for specific subsidies to afford a comfortable environment during summer.

A Justified Plan Graph Analysis of Social Housing in Mexico (1974\u20132019): Spatial Transformations and Social Implications

Space Syntax researchers have asserted that the spatial configuration of the planning of a work of architecture, such as a house, reflects how social properties are inscribed in its design. In social housing, the social inscriptions through space, which promote a particular way of dwelling, are not initially determined by the inhabitants. However, through appropriation, inhabitants mold the space to their liking, challenging preconceived ways of dwelling. Therefore, this research aims to determine what kinds of social structures the spatial configuration of social housing are promoting and how the inhabitants' transformations have altered the spatial experience. Mexico's housing sector developed from a “welfare approach” in the nineteen seventies and eighties to a “market rationale” since the nineties. During this time, different dwelling perspectives were inscribed in the spatial configuration of the homes. Using the justified plan graph (JPG) method, six social housing dwellings from these two time periods, Welfare State and market rationale, are spatially analyzed, both in their original design and in the resulting design from their inhabitant's modifications. Graph analysis is used in this paper for providing spatial insights into social housing design and its users' transformations, while pointing to further research needs.

Indoor Environmental Quality and Consumption Patterns before and during the COVID-19 Lockdown in Twelve Social Dwellings in Madrid, Spain

This article analyses the situation that prevailed in 12 dwellings located on the outskirts of Madrid during Spain’s state of emergency. How did 24/7 occupation affect the quality of indoor air and power consumption patterns? The mixed method used (surveys and instrumental monitoring) pragmatically detected the variation in consumption, comfort and indoor air quality patterns before and during the COVID-19 pandemic. The characteristics initially in place and household predisposition had a conclusive effect on such variations. The starting conditions, including household composition, habits and the way daily activities were performed, differed widely, logically affecting power consumption: 8/12 case studies increase occupancy density by more than 25 percent; 11/12 improve thermal comfort; 10/12 improve air quality but not necessarily translate in a sufficient ventilation practices; air quality was lower in the bedrooms on the whole; only 4/12 case studies use the potential of passive measures; only one household adopted energy savings strategies; 10/12 case studies increase electric power consumption but none of the dwellings was fitted with a renewable power generation system. The conclusion drawn is that, despite starting conditions differing widely, household composition, habits (including performance of daily activities performance) and power consumption also played an active role in the end result. This approach allowed to integrate qualitative and quantitative findings on indoor environmental quality (IEQ), energy use and households’ behavior. The objective data on the energy situation of the case studies not only is useful for the study, but also for potential enrollment in energy rehabilitation programs, such as the European Regional Development Fund (ERDF).

Imaginarios geográficos y desigualdad urbana en el Área Metropolitana de Buenos Aires (Argentina)

The present article aims to address geographical representations (also called urban imaginaries) of Buenos Aires Metropolitan Area´s inhabitants, about their urban region. In order to accomplish this goal, interviews were carried out with neighbors that reside in different types of housing (popular settlements, social dwellings both in height and single-family, low density middle-class neighborhoods, high density buildings and closed urbanizations). These interviews were analyzed and gave as result the predominance of urban imaginaries that naturalize metropolitan inequalities. Furthermore, it was possible to distinguish a system of social hierarchies (or socio-spatial order) between neighborhoods and differentiated geographical representations within neighborhood spaces, within the urban experience of its inhabitants.

In-situ investigation of the acoustical performance in collective social dwellings

With the lack of mandatory requirements to be observed by construction and building actors, acoustic performance becomes critical when considering overall comfort conditions in collective multistory dwellings alongside other factors such as those related to social and health conditions. However, despite the increasing number of complaints resulting from noise-related conflicts with neighbours, a very limited number of studies have been devoted to evaluating the acoustic performance of social housing. Hence, the aim of this study to assess objectively, through in-situ standardized measurements, the acoustical comfort within a sample of tunnel formwork multistory housing projects in Algeria. Given the lack of local national guidelines in this respect, a review of regulations implemented worldwide has been made to specify the most suitable descriptors for the case at hand. The acoustical performance considered in the present study concerns airborne, impact and façades sound insulation as well as those ratings used in acoustical housing classification schemes. Comparison of the results obtained to recommendations set by regulations, in countries with a long experience in the field, show that such type of housing can offer only poor to very moderate acoustics comfort to their tenant. This study enhances the urgency to develop a local mandatory regulation code setting clear acoustics requirements for coming housing projects for ensuring a minimum quality of the indoor acoustical environment for occupants and for avoiding undesirable noise-related disputes between neighbours.