Large Housing Stock Research Articles

The Diagnostics of the Condition and Management of Large-Panel Buildings Using Point Clouds and Building Information Modelling (BIM)

Technological developments involving the implementation of modern measuring equipment and the digitalisation of civil engineering can contribute to extending the service life of buildings. Large-panel buildings constitute a large housing stock throughout Europe. This paper presents the possibility of using laser scanning to identify typical assembly defects in large-panel buildings. Based on point cloud data, numerical models were created to assess the impact of improper assembly on the elements’ performance. It was indicated that using scanning to identify and monitor the displacement of structural elements does not relieve experts of the need to perform other tests. Analyses related to the possibility of using Building Information Modeling technology to manage large-panel buildings were also conducted. A parametric model was made, from which a number of possibilities of its use at every stage of the building’s life were presented in an example. It was highlighted that parametric models of large-panel buildings, due to their repeatable geometry, can be copied for use in managing entire neighbourhoods. Limitations associated with implementing BIM technology in practice were also formulated. The analyses and research performed confirm the validity of implementing modern research methods in engineering practice and digitising the documentation of large-panel buildings.

„Das ging ja nur hier…“ – Wohneigentümerstrukturen und Segregation in ostdeutschen Großwohnsiedlungen

Throughout the last two decades, large housing estates in eastern Germany have become the scene of an increased concentration of low-income households. At the same time, considerable shifts in the structure of home ownership have been documented in these areas. National and international investors have acquired large housing stocks here and become a fundamental part of the local housing markets. This paper discusses the connection between both developments. Based on a case study in two large housing estates in Halle (Saale) and Schwerin, it is argued that the relative impoverishment of large housing estates can be traced back to two developments on the supply side: On the one hand, municipal housing companies are increasingly made responsible for the provision of homes for households that cannot provide for themselves on the market. Due to the uneven spatial distribution of municipal housing, this leads to an increased concentration of poor households in the large housing estates. On the other hand, letting policies of financial investors are characterised by tight yield requirements. In view of a rather restrained demand for the housing they manage, they therefore increasingly rent their flats to population groups that are avoided by other landlords. Together, these developments operate like a ‘segregation machine’, which continuously shifts low-income population groups to the large housing estates.

Council tenancies and hoarding behaviours: A study with a large social landlord in England.

Hoarding behaviours are highly stigmatised and often hidden. People with problematic hoarding behaviours have a higher rate of mental health and other healthcare and social services utilisation. Hoarding is a community health problem, one factor being housing insecurity. Hoarding behaviours represent significant burden to housing providers, impact the community and dealing with it involves multiple community agencies. This study with a city council in England with a large housing stock (over 14,000 properties) in summer 2021 sought to understand the nature, circumstances and extent that hoarding presents. We developed a reporting system and conducted 11 interviews with housing officers in which they described a case to explain their involvement. Our report details the nature of 38 people who hoard: 47% had a known disability or vulnerability, 34% presented a fire and environmental risk, 87% lived alone and 60% were resident in flats. Our qualitative themes are: Working with others, Balancing an enforcement approach, Feeling conflicted, Complex needs of people who hoard and Staff needs. The cases described by the housing officers are combined into six case studies and illustrate the complex, multi-agency circumstances around decision making and risk stratification. Our findings point to housing officers as frontline professionals dealing with a public health and social care issue which is often the manifestation of complex life histories and mental health conditions. We suggest a greater focus on risk stratification and a more holistic approach to hoarding cases to effectively deal with this most complex of community health and social care issues.

Low-carbon retrofits in social housing: Energy efficiency, multidimensional energy poverty, and domestic comfort strategies in southern Europe

Social housing providers have a significant amount of influence over large housing stocks, which gives them unique opportunities to address both energy efficiency and social inclusion. However, there are significant barriers to achieving these goals in southern European contexts, where obsolete housing stocks and widespread energy poverty situations combine to create a “prebound effect”, whereby residents consume less energy than in projections of standardised patterns, thus invalidating models based on energy efficiency gains and energy production. This paper uses empirical findings from interviews with social housing providers in the metropolitan areas of Porto [Portugal] and Barcelona [Spain] to understand how this contradiction is being handled in the sector, and compares the findings with surveys of the nature and depth of energy poverty situations in a broadly defined social housing sector. Our results show that social housing providers tend to favour strategies based on retrofitting the envelopes of the buildings, and to resist installing renewable energy equipment, for which cost recoupment is near-unachievable. We argue that this focus on achieving thermal comfort by passive measures overlooks the multidimensionality of energy poverty situations in the social housing sector, with widespread practices of restrictions on cooking, lighting and DHW uses.

The Challenges of the Redevelopment of Old and Dilapidated Buildings in Mumbai: A Policy Perspective

Affordable housing is the biggest challenge being faced by the city of Mumbai, which styles itself as an emerging Global Financial Centre. The city has the image of being home to a stark dualism, with slums abutting modern skyscrapers. Over the years, adequate policy attention has been given to slums and with the implementation of the Slum Rehabilitation Scheme slum dwellers are being provided with housing in multi-storey buildings and are being granted tenancy rights to the dwellings. However, an emerging area of concern is the large housing stock that is non-slum but is old and dilapidated. The collapse of an old and dilapidated building in Dongri in July 2019 that killed twelve people and the one at Bhendi Bazaar in 2017 that killed thirty-three has brought this problem into the mainstream and new policies have been initiated to address the problem. Implementing these policies seems to be a challenge, and this is the result of different factors. This article looks at the housing problem in Mumbai from a policy perspective and analyses the implementation challenges of the new policy aimed at redeveloping the old and dilapidated housing stock.

Robustness of energy consumption and comfort in high-performance residential building with respect to occupant behavior

Building energy simulations rely on assumptions that can affect their reliability. Occupant behavior in particular is highly uncertain, especially for residential buildings. The great variability of occupants’ actions has a great impact on the energy performance of a building and can explain the failures of building simulations to accurately forecast the energy demand of a building. This study quantifies the impacts of humans on the performance of a residential building by simulating dwellings using multiple realistic occupant behavior profiles. The dwelling models were validated with monitored data. Aspects of occupant behavior covered in this study are occupancy, hot water and electricity consumption, heating set point temperature and openings of windows. The individual impact of all these aspects on energy demand and thermal comfort are analysed. Results show great variability of energy consumption and thermal comfort for a given dwelling when different occupants are living in it, with coefficient of variation of approximately 50%. Large housing stocks are less sensitive to occupant behavior than individual dwellings, but their consumption levels remain difficult to predict when using a deterministic approach to represent occupant behavior.

Application of an indoor air pollution metamodel to a spatially-distributed housing stock

Estimates of population air pollution exposure typically rely on the outdoor component only, and rarely account for populations spending the majority of their time indoors. Housing is an important modifier of air pollution exposure due to outdoor pollution infiltrating indoors, and the removal of indoor-sourced pollution through active or passive ventilation. Here, we describe the application of an indoor air pollution modelling tool to a spatially distributed housing stock model for England and Wales, developed from Energy Performance Certificate (EPC) data and containing information for approximately 11.5 million dwellings. First, we estimate indoor/outdoor (I/O) ratios and total indoor concentrations of outdoor air pollution for PM2.5 and NO2 for all EPC dwellings in London. The potential to estimate concentration from both indoor and outdoor sources is then demonstrated by modelling indoor background CO levels for England and Wales pre- and post-energy efficient adaptation, including heating, cooking, and smoking as internal sources. In London, we predict a median I/O ratio of 0.60 (99% CIs; 0.53–0.73) for outdoor PM2.5 and 0.41 (99%CIs; 0.34–0.59) for outdoor NO2; Pearson correlation analysis indicates a greater spatial modification of PM2.5 exposure by housing (ρ = 0.81) than NO2 (ρ = 0.88). For the demonstrative CO model, concentrations ranged from 0.4–9.9 ppm (99%CIs)(median = 3.0 ppm) in kitchens and 0.3–25.6 ppm (median = 6.4 ppm) in living rooms. Clusters of elevated indoor concentration are found in urban areas due to higher outdoor concentrations and smaller dwellings with reduced ventilation potential, with an estimated 17.6% increase in the number of living rooms and 63% increase in the number of kitchens exceeding recommended exposure levels following retrofit without additional ventilation. The model has the potential to rapidly calculate indoor pollution exposure across large housing stocks and estimate changes to exposure under different pollution or housing policy scenarios.

Ocena standardu komunalnego budownictwa mieszkaniowego w małym mieście na przykładzie Twardogóry i Chocianowa

Stan zabudowy mieszkaniowej wielorodzinnej zależy od polityki miasta w zakresie kształtowania zasobu komunalnego. Jest to zauważalne w porównaniu dostępności i standardu technicznego budynków. Autorka w niniejszym artykule analizuje kierunki zagospodarowania przestrzennego gminy i zestawia je ze szczegółową oceną stanu zabudowy mieszkaniowej wielorodzinnej w wybranych małych miastach do 10.000 mieszkańców: Chocianowie i Twardogórze (zlokalizowanych w woj. dolnośląskim) – miastach prezentujących strategię utrzymania dużego zasobu mieszkaniowego, a przez to kontroli nad kształtowaniem zabudowy. Artykuł prezentuje jeden z etapów realizowanego projektu badawczego – szczegółowa inwentaryzacja mienia komunalnego i analiza dokumentów planistycznych w 2 małych miastach o zbliżonej polityce mieszkaniowej, liczbie ludności, bez wpływu miasta metropolitalnego – który ma na celu próbę stworzenia optymalnego modelu zagospodarowania komunalnych terenów mieszkaniowych w śródmieściach małych miast do 10.000 mieszkańców w województwie dolnośląskim.

Social housing providers as unlikely low-carbon innovators

Social housing providers have recently emerged as unlikely innovators of low carbon transitions in the UK residential sector. They tend to have a significant amount of influence over large housing stocks, opportunities to access funding to retrofit on a large scale, can make explicit connections between reduced carbon emissions and improved quality of life for low-income residents, and foster a close relationship with the place and communities they serve. In effect, social housing providers are ‘middle actors’ who not only facilitate but also realise low carbon transitions through various strategies. This paper uses empirical findings from interviews with social housing providers in Greater Manchester to understand the different ways that low carbon and energy efficiency innovation is being undertaken in this sector. The findings reveal that as middle actors, social landlords influence upstream to policy makers and regulators, downstream to individual households, and sideways to other actors in the social housing sector as well as to other building and energy professionals. The findings reveal opportunities for governments to supplement their existing policies with recognising and supporting middle actors to accelerate low carbon transitions of the built environment.

Energy-saving potential of large housing stocks of listed buildings, case study: l'Eixample of Valencia

A significant part of the European residential building stock is architectural heritage and is protected by law in different grades. Although these dwellings seldom fulfil the current eco-efficiency requirements, listed buildings are exempt from energy regulations requirements. This paper reviews the constructional characteristics common to 588 multi-storey listed buildings (circa 6000 dwellings) located in l’Eixample district in Valencia (Spain). The poor thermal performance of these buildings proven by this study reveal a significant potential for saving energy and reducing CO2 emissions, particularly when considering the current requirements fixed by the current Spanish building code. Retrofitting measures intended to improve the thermal behaviour of these buildings, while being respectful to their listed nature, are proposed and assessed in terms of energy demand, air pollution and economy.

Energy retrofit alternatives and cost-optimal analysis for large public housing stocks

The study of cost effective solutions for the energy retrofitting of existing buildings is of capital importance for building asset owners, since high up-front investments are required and long payback times are encountered in building renovation projects. The aim of the work is to propose a decision support system (DSS) for the assessment of different renovation strategies through the measure of their economic sustainability in relation to the achieved energy efficiency. The cost optimal analysis of energy retrofit alternatives is performed in the case of a large housing stock owned by a semi-public real estate company, with the goal of meeting nearly zero energy building standards. Energy performances as well as related energy and construction costs are analysed for different retrofit options, adopting Italian laws and regulations. The proposed DSS evaluates the economic sustainability of various design alternatives with the net present value (NPV) and the global cost (GC), as suggested by the EPBD recast EU directive. These indicators are finally compared with the building energy performance index (EP), providing the most efficient design alternatives for each building typology and the most advantageous renovation project among the considered ones.

Is there an S in urban housing supply? or What on earth happened in Detroit?

This article examines the substantial housing stock declines between 2000 and 2010 in many major US central cities. It updates an analysis first formulated in the 1970s, of an S-shaped housing supply curve, to explain decreases in absolute housing stocks. Explanatory variables include Metropolitan Statistical Area standardized rents, center city prior occupancy rates, regional unemployment rates, and a set of regional and state dummy variables. The analysis provides strong evidence of a lower tail of the S, and more tentative evidence of an upper tail. Market fundamentals explain a considerable portion of the large housing stock losses, but in several cities loss of dwelling units and housing abandonment were worse than could be explained by the fundamentals.

On the development of unmodified mud grouts for repairing earth constructions: rheology, strength and adhesion

The conservation and rehabilitation of several sites of cultural heritage and of the large housing stock built from earth requires the development of techniques and materials compatible with this kind of construction. Grout injection is one repair solution which has been put forward over the last few years, whereas there is preference for employing grouts that incorporate earth in their composition. However, knowledge of such grouts is still very limited and requires further research. The experimental program discussed in this paper contributes to the comprehension of the influence of the composition of an unmodified mud grout, namely regarding its fresh-state rheology, hardened-state strength and adhesion. In general, the results obtained showed that the rheological behaviour of a mud grout greatly depends on the colloid behaviour of the clay fraction, and that the addition of a deflocculant and modification of the clay content (with a silt size material) is required to obtain grouts with adequate solid fractions.

The impact of long-term loading and changes in moisture content and relative humidity on timber purlins and beams

A common problem found in surveys of domestic residential properties — in particular for clients with large housing stocks such as local authorities — is deflection in timber purlins and beams. Timber's performance changes with long-term loading and variations in humidity and moisture. Changing the building environment can have a dramatic effect on timber components, but sometimes things are not as straightforward as first thought. This paper considers how the environment of a building can affect the performance of timber members.

Truss rafter roof support: How risk from inherent building defects is being exacerbated by changing climatic conditions

Specialising in surveys of domestic residential properties and, in particular, clients with large housing stocks such as local authorities, the author's company is finding an increasing number of defects in the housing stock built in the 1960s and 1970s. In this paper, the author considers how these inherent defects are exacerbated by the changing climate such as the increase in wind speed and frequency of gale force winds.

The Million Homes Programme: a review of the great Swedish planning project

The first decades of the post‐war era saw a large and quickly growing need for new housing. In Sweden, rapid urbanization, growing prosperity and demands for higher housing standards led to years‐long housing queues. The housing shortage became a political liability for the ruling Social Democratic party. To end the housing shortage once and for all, the Swedish parliament decided that a million new dwellings should be built in the period 1965 to 1974 and this was achieved. When the Million Homes Programme, as it came to be called, had reached barely half‐way, the housing shortage was replaced by a housing surplus, partly caused by the rapid expansion of the housing stock and by the fact that economic growth gave way to stagnation. At the same time, criticism began to be heard about what some people perceived as uniform and poor architecture and, since then, the Million Homes Programme has never ceased to engage people and provoke debate. Most of the buildings and areas of this era have survived quite well with routine maintenance, but in several multifamily housing areas more thoroughgoing measures have been needed. The development patterns can be divided into six categories: everything from maintenance and conventional daily care to large‐scale turn‐around and demolition. The housing construction of the ‘record years’ is typical of its period in modern Swedish history. In the 1960s the ambition was to create an exemplary welfare state – many people no doubt imagined the best in the world – and for this ambition the spacious and ultramodern buildings of the Million Homes Programme were a fitting expression. Sweden had been transformed from a country with a housing shortage to a country with a housing surplus. Today, again facing considerable housing shortage in many growing cities, developing this large housing stock with care for its qualities and its residents, and learning from the mistakes where new developments are needed, are important tasks.

Assigning priorities for maintenance, repair and refurbishment in managing a municipal housing stock

The municipality of Lisbon owns a large housing stock that requires maintenance, repair and refurbishment. Taken together, these activities imply a financial effort each year that clearly exceeds the available budget, and therefore it is critical that the decisions on which sub-set of potential activities should be carried out in each coming year are based on sound analysis and evaluation. The design and construction process of a model to assist the Lisbon Municipality to assign priorities to these activities is described. The macbeth approach was extensively used, in an interactive and constructive process, to derive the value functions associated with each criterion and their respective weights, reflecting municipal policies and their officials preferences and attitudes. The paper also presents the procedure used to determine multidimensional reference-profiles that define urgency categories, enabling to assign each potential action to one of these categories. Finally, a specific model was defined to aggregate elemental building jobs in “packages”, when there are arguments (in terms of cost reduction, action coherence, urban environment impact synergies, etc.) that favour their joint execution under a single contract.