No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Replacement or renovation of dwellings: The relevance of a more sustainable approach
Abstract
The choice between replacement and life cycle extension of existing buildings implies a vital but very difficult decision, involving a wide range of aspects and affecting contradictory and often conflicting interests. Originally, building quality and public health played a decisive role in improvement of the housing stock, mainly by slum clearance. More recently, functional and economic considerations tend to dominate the decision-making, resulting in increasing demolition and demolition waste. Although environmental aspects (e.g. energy consumption and building waste) are of growing importance, sustainability does not seem to be a major aspect in the choice between demolition and life cycle extension until now. To address the questions of what is more sustainable: replacement or life cycle extension, the decision-making processes surrounding housing demolition in the Netherlands are analysed and a conceptual framework is created. Sustainability has the potential to be a major criterion in housing stock management and, in particular, on the decision processes about dwelling replacement or life cycle extension. From that point of view, life cycle extension is often a better solution than demolition.
... If a building is retained rather than demolished, usually, fewer materials are required for the project, thus lowering embodied energy and associated carbon dioxide emissions. However, a counterargument is that existing buildings cannot reach the same operational energy standards as new builds, which could cause the emissions over the entire life cycle of the building to be higher (Ball, 2002;Davis Langdon, 2008;Thomsen and van der Flier, 2009). Palmer et al. (2003) showed that existing buildings could be made as energy efficient as new builds, but other variables will affect this decision, such as cost and whether the building will be owner occupied. ...
... Less material use (embodied energy) Ball (2002), Bullen and Love (2010), Clegg (2012), Conejos et al. (2011), Gaspar andSantos (2015), Itard and Klunder (2007), Lin and Low (2012), Remøy and Van der Voordt (2006), Thomsen and Flier (2009) showing that the historic environment creates a price premium (Ahlfeldt et al., 2012;Been et al., 2016;Lazrak et al., 2013;Noonan and Krupka, 2011;Ruijgrok, 2006). Despite this range of studies, others describe the difficulty of quantifying heritage without the support of 'hard evidence' (Wilkinson et al., 2014). ...
... Poor building quality/condition leading to increased costs Ball (2002), Bullen and Love (2010), Lin and Low (2012), Thomsen and Flier (2009) ...
This paper considers why the decision may be made either to demolish or adapt existing buildings on brownfield sites and compares real-life decisions to those produced by theoretical design-support tools. Five case studies, including three individual buildings and two master plan sites of multiple buildings, were investigated through interviews with stakeholders. Reasons for retention included heritage value, architectural quality and government incentives, while reasons for demolition included maximising land value, lack of architectural significance and poor building condition. The analysis showed that the theoretical tools were useful for their intended purpose of analysing a portfolio of assets but that they could be improved by providing higher weightings for heritage values and extending the tools to assess different end uses and forms of adaptation. By testing the tools on master plan sites, the paper also identifies urban design variables, such as land efficiency, which would need to be incorporated for this purpose.
... Public owners can also be expected to foster social responsibility, although this is not always the case, while private non-professionals may be influenced by secondary motives such as emotional ties. (Thomsen & van der Flier, 2009). Their motives likely also differ depending on whether they use the dwelling as their home or if they rent it out. ...
... In multi-family buildings (row houses and blocks of flats), the decision-making is collective, whereas detached house owners and professional landlords usually have more freedom, since they tend to own the whole building. (Thomsen & van der Flier, 2009). However, the ownership of detached houses may also be dispersed between heirs or members of an undistributed estate, complicating the decision-making. ...
... However, it should be noted that there were significant differences in the replacement behaviour between urban and rural areas. The findings on tenure types suggest that the limitations posed by shared ownership as described in Thomsen and van der Flier (2009) would, indeed, have an effect on the demolition of buildings. ...
Vacant housing has been associated with a variety of interests from economic implications and consequences for the urban structure to the possibility of providing housing for the homeless. In addition to these social and financial aspects, unused buildings have resources embedded in them. They take land from other activities and contain refined natural resources in the form of building components and materials. Therefore, empty buildings can be regarded as reserves for housing and repositories for urban mining, i.e. material extraction. In doing so, these buildings contribute to the resilience of cities. This geographical and statistical study on residential vacancies is situated in Finland, where empty homes may also keep using energy and producing emissions. The research material consists of a vast dataset of all residential buildings with vacancies in Finland in mid-2014, a total of 275 486 buildings with 1 100 267 occupied and 378 802 unoccupied dwellings (52% of the Finnish housing stock). The paper shows several characteristics that increase the understanding of vacancies and their role in the dynamics of the building stock. Public policy should address the issue of vacancy, not only because of social and economic implications but also because of its environmental impacts and opportunities.
... Apart from detached houses on high-value lots, demolition cases are almost absent in the owner occupied sector (cf. Thomsen and van der Flier, 2009). ...
... All the cases are renovation projects; demolition cases are almost absent in the commercial rented sector (cf. Thomsen and van der Flier, 2009). ...
... (3) In the commercial rented sector, in particular small and mid-size private owners, a pattern similar to the social rented sector can be observed, albeit that the limiting condition of sufficient return on the investment is crucial. In line with previous findings (Thomsen and Van der Flier, 2009) property objectives and investment capacity play a decisive role. ...
Purpose
– In previous research publications the authors combined the available knowledge about obsolescence in a conceptual model for further research on and appliance in the decision making about demolition. Since evidence-based theoretical research references on obsolescence are rare, the model inevitably had an explorative character. The purpose of this paper is to test and elaborate the model.
Design/methodology/approach
– A series of case studies were conducted in various residential building estates. In each estate the types of obsolescence (according to the model) and their interrelationships were identified.
Findings
– The model can usefully be applied; it enables the determination of types of obsolescence. The case studies also show that several types of obsolescence occur simultaneously, and that these types can be interrelated. This touches upon the complexity of cause-effect mechanisms as already mentioned in the introduction. One of the weaknesses is that information is sometimes available for only one point in time, and that the availability of information varies with the type of obsolescence.
Research limitations/implications
– The study is based on a limited selection of case studies. Further, the causal relationships between the types of obsolescence could not always be revealed.
Practical implications
– The current model does not distinguish between causes and effects. For further development of the model, cause-effect processes have to be further analysed.
Social implications
– Actual measurement of the extent of obsolescence per type is not part of this study, but has to be carried out before social implications can adequately be indicated.
Originality/value
– The paper presents a conceptual classification of obsolescence that turns out to be workable when tested in practice.
... There is a major difference between the rates for RB and NRB: the former was on average 0.05% whereas the latter was 0.68%, that is, more than 13-fold. The Tampere RB demolition rate is in the same scale as in other West and North European countries (cf., van der Flier & Thomsen, 2009). Previous research (e.g., Bradley & Kohler, 2007;Huuhka & Lahdensivu, 2016) has identified that the rates for NRB tend to be larger than for RB, but in Tampere, the phenomenon is more intense. ...
... Typically, these are distinguished not only by the function but also by the ownership structure (number of owners, complexity of decision-making) and interests of owners (profit-driven motives of professional owners vs. service-or attachment-driven motives of private owners) (cf., Bradley & Kohler, 2007;Thomsen & van der Flier, 2011). For instance, the demolition rates of rental housing can be much higher than for similar owner-occupied housing (van der Flier & Thomsen, 2009), which demonstrates the significance of ownership. ...
Research has identified cities as potential urban mines for recovering secondary construction materials. Studies typically focus on stocks or flows of bulk materials on high abstraction levels. To enable a shift of focus towards higher levels of circular economy, such as waste minimization, there is a need for a more detailed understanding of the dynamics that contribute to the waste flows, building replacement in particular. This paper examines the characteristics and location of the stocks and flows of buildings in the city of Tampere, Finland, over the last 20 years. Statistical and geographical analyses are performed on the building stock, new construction and demolition in Tampere to unveil patterns pertaining to stock change and building replacement. The study shows that these patterns vary significantly between buildings of different function. Spatially confined redevelopment areas within the city structure, i.e. brownfields and greyfields, whose industrial and commercial functions yield to housing and mixed residential-commercial use, make up major arenas for replacement. Policy-making should acknowledge that urban planning stirs these waste flows and incorporate their conscious prevention and management on its agenda.
... If a building is retained rather than demolished, usually, fewer materials are required for the project, thus lowering embodied energy and associated carbon dioxide emissions. However, a counterargument is that existing buildings cannot reach the same operational energy standards as new builds, which could cause the emissions over the entire life cycle of the building to be higher (Ball, 2002;Davis Langdon, 2008;Thomsen and van der Flier, 2009). Palmer et al. (2003) showed that existing buildings could be made as energy efficient as new builds, but other variables will affect this decision, such as cost and whether the building will be owner occupied. ...
... Poor building quality/condition leading to increased costs Ball (2002), Bullen and Love (2010), Lin and Low (2012), Thomsen and Flier (2009) ...
This paper considers why the decision may be made either to demolish or adapt existing buildings on brownfield sites and compares real-life decisions to those produced by theoretical design-support tools. Five case studies, including three individual buildings and two master plan sites of multiple buildings, were investigated through interviews with stakeholders. Reasons for retention included heritage value, architectural quality and government incentives, while reasons for demolition included maximising land value, lack of architectural significance and poor building condition. The analysis showed that the theoretical tools were useful for their intended purpose of analysing a portfolio of assets but that they could be improved by providing higher weightings for heritage values and extending the tools to assess different end uses and forms of adaptation. By testing the tools on master plan sites, the paper also identifies urban design variables, such as land efficiency, which would need to be incorporated for this purpose.
... Of those, construction minerals are probably the materials which have the longest use phase and lifespan. A recent study by Haas and colleagues showed that over 99% of the 24 Gt of construction materials that entered the economy struction sector, i.e. construction demolition waste data, is hard to come by (Thomsen and van der Flier, 2009). In rare cases, demolition data is collected at the national level, allowing for analysis of trends and the spatial distribution of demolitions for the whole country (Huuhka and Lahdensivu, 2016). ...
... It is generally agreed that a better understanding of the dynamics that characterise the construction and demolition of buildings is a necessary step towards a more sustainable built environment (e.g. Aksözen et al., 2016a;Allen and Hinks, 1996;Thomsen and van der Flier, 2009;Thuvander et al., 2015) Tanikawa and colleagues identified four different approaches to material stock accounting, including bottom-up accounts, topdown accounts, demand-driven accounts, and accounts based on remote sensing technologies (Tanikawa et al., 2015). Each of these methodologies has its own strengths and weaknesses. ...
Accurate assessments of construction materials stocked in the built environment have received increased attention in the Industrial Ecology literature over the past few years. Many recent models that estimate building material inflows, stock accumulation and end-of-life waste, however, rely on simplistic assumptions about the lifespan of built infrastructure. While several probability distributions have been proposed (normal, Weibull, log-normal, and so on) there is no agreement on which model is best suited for modelling the accumulation of building material stock at urban and national levels. In this study we introduce an analysis of the hazard rate of buildings and discuss alternative distribution functions to model lifespan, testing the fit of five commonly used distributions to real data from the cities of Nagoya (Japan), Wakayama (Japan), and Salford (UK). The results highlight how cities with fast replacement rates are overall best modelled by right-skewed distributions, but single cohort levels express independent behaviours based on their characteristics. We investigate the sensitivity of a top-down stock accumulation model to the choice of different distributions and input parameters uncertainties. The results show that different lifespan distribution functions result in very similar overall stock accumulation at the national level, but have large impacts on calculated demolition waste flows. Differences are more pronounced for cities and the choice of a certain distribution will significantly affect the calculation of the average lifetime. Our results suggest that top-down national material stock accounts have high reliability, and are only weakly affected by the choice of one distribution over another. For cities, it is beneficial to use a distribution based on the characteristics of the buildings analysed, with regard to density and building characteristics. Stock accumulation research would profit from future bottom-up research into building lifespans to validate top-down estimation procedures.
... New theories and empirical tests also coincided with societal and governmental reconsideration of demolition and redevelopment of older-urban houses as an effective method of planning for them (e.g., [10]- [12]). Even aside from the social and environ-mental consequences, the private rehabilitation of existing modest housing should always be less expensive than the construction of new comparable housing [13] [14]. ...
... Residents' and absentee owners' maintenance and improvement of their homes is normally explained as being motivated to maximize the home's current or future subjective value or utility subject to constraints [14] [19]- [21]. Individuals thinking about the utility of the home in terms of its flow of economic, environmental, social and psychological services should therefore invest their time and money into maintaining and improving those services it provides [22] [23]. ...
... La durée de vie des bâtiments est généralement considérée dans ses dimensions physiques ou fonctionnelles. Elle reflète respectivement la dégradation progressive des performances physiques et mécaniques initiales ou la capacité fonctionnelle à répondre à l'usage prévu [170]. ...
Le bâtiment est considéré comme le premier secteur consommateur d'énergie dans le monde. Au Maroc, face à la crise économique et aux engagements pris pour limiter les effets du réchauffement climatique, il est devenu impératif de réduire la consommation énergétique des bâtiments. Dans ce contexte, la recherche de solutions techniques optimales au regard des performances liées à la demande d'énergie et au confort est un problème très complexe en raison du nombre élevé de paramètres à prendre en compte. Pour remédier à ce problème, un état de la technique des méthodes existantes dans cet axe de recherche est réalisé. Celui-ci nous a amené à constater que plusieurs lacunes existent dans l'utilisation de ces méthodes, principalement le temps de calcul élevé qu'elles nécessitent et le manque de contrôle de la convergence des résultats vers les optima globaux recherchés.Cette thèse a pour objectif principal le développement d'une nouvelle méthode puissante, fiable et rapide pour la conception de bâtiments confortables et efficaces sur le plan énergétique. En se basant sur des outils de simulation numérique et sur les techniques d'intelligence artificielle, nous avons développé avec succès des modèles de substitution permettant la prédiction optimale des besoins énergétiques et du confort thermique pour le cas des bâtiments résidentiels. Le choix et la configuration des variables de conception sont soigneusement établis sur la base de l'état actuel de la technique, soutenu par une analyse de sensibilité, afin de mieux comprendre à la fois l'influence de chaque variable sur la performance attendue et la corrélation entre elles. Cela nous a permis de formuler mathématiquement le problème à optimiser, dont la résolution entraîne la recherche de solutions optimales dans une dimension multi-objectif. A l'aide des algorithmes métaheuristiques, le processus d'optimisation est réalisé avec succès conduisant à la génération de la frontière de Pareto optimale, qui n'est autre qu'un ensemble de solutions optimales par rapport aux critères considérés. Cet ensemble de solutions permet d'atteindre l'objectif souhaité avec une très bonne précision, et surtout un temps de calcul drastiquement réduit. Cette méthode peut donc être un outil très efficace pour aider les concepteurs et les décideurs dans le domaine de la construction à concevoir des bâtiments confortables et à haute efficacité énergétique.
... However, it has been shown through various studies that, when considered as a whole, buildings seldom reach their maximum value, conventionally assumed for the end of a building's service life. According to Thomsen and van der Flier [74], defining the instant after which a building fails to comply with the essential performance requirements is a very challenging task. In practice, the end of a building's physical service life can be limitless, when regular and adequate maintenance policies are in place, and a building can, in contrast, be demolished long before reaching its physical or functional limit due to social or legal motives [75]. ...
In the last decades, considerable work has been done regarding service life prediction of buildings and building components. Academics and members of the CIB W080 commission, as well as of ISO TC 59/SC14, have made several efforts in this area and created a general terminology for the concept of service life, which is extremely relevant for property management, life cycle assessment (LCA) and life cycle costs (LCC) analyses. Various definitions can be found in the literature that share common ideas. In fact, there are different criteria that trigger the end of a building’s service life, but the trap that building practitioners too often fall into and that should be avoided is dividing a problem into separate boxes, labels, and specializations without the mutual cohesion and interaction, and ignoring human behavior. Some definitions of service life are discussed in this review paper, in which the cause-effect processes underlying aging and decay are described. These descriptions highlight the continuous interrelation between different criteria for the end of a building’s service life, considering too often neglected and misunderstood causes of the end of life.
... Domestic extraction refers to when the construction material is sourced within the study area and correction factors refer to the adjustments made due to statistical and calculation errors. The process of calculating the values required for each input involves certain complexities such as the availability of data, employment of adequate techniques, and assumptions [5,6]. Hence, there has been an increase in research articles developed to streamline the process of calculating construction material stock using different methodologies [7][8][9]. ...
This paper aims to critically review the current body of literature relating to the calculation methods of construction material stock. To this end, this study adopts a systematic literature review technique in order to identify the relevant studies. The findings revealed that the bottom-up and top-down methodologies were commonly employed by the reviewed studies. Based on the findings, it is recommended that the bottom-up approach should be utilized when dealing with small-scale areas or where more accurate results are required. The top-down method should be used wherein the research area is large, and the results could be estimated based upon assumptions and statistical data. Similarly, the demand-driven methodology should be used to find the material stock accumulation due to socio-economic factors. The study also found that the material stock results can be used as data for other research, such as waste management and embodied energy. Further, this paper proposes a conceptual framework to ease the process of calculating construction material stocks in different projects. The outcomes of this research shall be beneficial for future studies that explore the literature connected to the construction material stock and recommend methods and techniques that should be used to quantify the material stock.
... Hasik et al. conducted a comparative between refurbishment and new construction by a whole-building life cycle assessment, which showed that 53-75% reductions when the refurbishment was compared to rebuilding strategy in terms of acidification potential, eutrophication potential, global warming potential, ozone depletion potential, smog formation potential and non-renewable energy demand [23]. For materials and waste, the environmental impact of refurbishment strategy is better rebuilding strategy [24]. ...
Many cities have encountered challenges associated with rapid urban development, population growth and aging, in which urban renewal has become a promising option. Different renewal strategies, such as redevelopment, refurbishment and conservation, not only contributes to quality improvement and energy consumption reduction of dilapidated urban area, but also to greenhouse gas (GHG) emissions mitigation. Such integrated benefits are often termed as co-benefits. However, choosing the most co-benefits strategy to adopt requires a holistic understanding of social-economic and environmental aspects, which has been less reported in the existing literature. Under such circumstance, this article aims to shed light on the co-benefits of different renewal strategies by adopting the Emergy-Life cycle assessment method. Then, the method is applied to one case study of the refurbishment of an educational building located in Chongqing, China. Resource allocation, CO2 emissions and emergy-based indicators are calculated to assess the co-benefits during a 60-year research period, to compare the impacts of the complete demolition followed by a new one (rebuilding strategy) and the refurbishing of the existing building (refurbishment strategy). The case study shows that the annual emergy in the O&M phase of rebuilding strategy and refurbishment strategy were lower than existing building. Rebuilding and refurbishment strategies released approximately 59.1% and 80.6%, respectively, of the total CO2 emissions that would be produced by the existing building. The results reveal that substantial environmental benefits can be obtained in both the refurbishment and rebuilding strategies. On the other hand, it can be concluded that the emergy yield ratio (EYR) for the rebuilding strategy is higher than refurbishment strategy, which demonstrate the better performance of refurbishment considering that less resources are required to generate greater benefits. In addition, the value of environmental loading ratio (ELR) and emergy sustainability index (ESI) also suggests that the refurbishment strategy performs better from the perspective of the environment. Thereby, the refurbishment strategy is more suitable than the rebuilding strategy. Findings from this study can be useful to urban planners and decision-makers in choosing the most suitable strategy to improve the quality of existing buildings.
... Some studies (Lima Gaspar and Santos 2015; Weiler et al. 2017) reveal that building refurbishment is a more sustainable strategy than new construction as it represented a lower material intensity and embodied energy consumption and less demolition waste. The environmental impact of life cycle extension through renovation in most cases is lower than demolition and new construction, although in practice (up to now) the higher energy performance of new construction after demolition reduces the differences (Thomsen and Van Der Flier 2010). In other studies, assuming the energy performances of the refurbished and the rebuilt options as equal, the material input and the construction phase represent the highest impacts. ...
In the building sector, new standards for energy efficiency are reducing the energy consumption and the carbon emissions for building operation to nearly zero. As a result, the greenhouse gas emissions and related environmental impacts from materials production, and especially insulation, are becoming key factors. In the near future, most of the building stock is expected to be refurbished and a great amount of construction materials will be consequently required. A relevant share of waste is generated from building construction and demolition and limiting the volume is a priority of the EU community. In this work the renovation of industrial buildings in a dismissed area located in Lecco, Italy, was considered as a case study. Five alternative construction systems (EPS, WOOD, ROCK, PU, HEMP) for renovating the building envelopes were assumed, and a life cycle assessment (LCA) adopted in order to measure the environmental impact of each alternative. The results were compared with a scenario which included demolition and reconstruction of a similar building with the same net volume and thermal resistance. The results showed that timber and concrete are the most environmentally friendly materials to rebuild the structures in case of demolition, contrary to steel which leads generally to higher environmental impacts, except land use. In general, EPS, WOOD and HEMP technological alternatives accounted for the highest scores, both in terms of burdens on the ecosystems and on depletion of resources, while ROCK accounted for the lowest scores. Finally, refurbishment scenarios generally accounted for a lower global warming potential (GWP) even if demolition, waste treatment and the benefit from recycling/reuse are taken into account.
... Building renovation measures lead to the better environmental performance of the building, more productivity in the use of local resources, and less pressure on the local ecosystem (Andri c et al., 2017). Overall, building renovation is preferred to demolition due to less destructive environmental impacts (Itard and Klunder, 2007;Thomsen and van der Flier, 2009). Additionally, the importance of conserving the cultural heritage and old masonry buildings is a justification for the concerns of different countries around the world (Cardoso et al., 2005). ...
Urban revitalization provides a chance to rethink ways to achieve sustainability and resilience in a district. In recent years, the need for a deliberate plan to renovate existing buildings has been contemplated more than ever. The renovation process can be considered a capacity to implement sustainable and resilient development factors leading to original architecture conservation. With that being said, having an understanding of the various sustainability and resilience dimensions is required before taking any actions.
This article presents a sustainable-resilient urban revitalization framework called SRUR for the renovation of existing residential buildings in a historic district by applying the Delphi method. Through the use of SPSS, Expert choice software and analytic hierarchy process, the respondents’ awareness of sustainability and resilience, the importance of each factor, prioritization of dimensions and promotion strategies are evaluated through a survey of 165 construction experts and 76 dwellers in Zanjan, Iran. The results show that location, transportation, building added value and quality of life are the most important factors. Additionally, more than 80% of respondents believe that adhering to the sustainability and resilience considerations will increase the cost and time of the projects. Finally, in addition to stronger governmental support, the city also needs informed people and trained specialists in order to achieve its plan towards sustainable and resilient renovation. Moreover, managerial implications are defined for managers and experts in charge of decision-making in urban revitalization.
... Renovation has important implications for sustainability. On the one hand, in terms of resource use and environmental impact, renovation is often a better choice compared with demolition and new construction [1,2]. Studies have shown that the technical and economic life of a building exceeds the estimated service life of the building [3,4]. ...
Housing renovation, in contrast to new construction projects, has to take good care of the tenants who are already living in the building. What are the theoretical and practical implications concerning the transformation from a technology-and-engineering-focused renovation approach to a more user-oriented one? What are the mechanisms of strategy change? Based on our case we argue that the mechanisms of strategy change are based on the interplay between external disturbance and internal renewal. External disturbance is the trigger of strategy change, but it does not, in itself, necessarily lead to strategy change, and particularly not for an innovative new strategy. The internal new competence is the source of changing from an old strategy to an innovative new strategy. The real estate industry needs to undergo a transformation from the rationalistic technology- and engineering-focused renovation model (TEF model) to a more inclusive approach. We suggest a user-oriented model (UO model) where user involvement is seen as integrated in the whole process of renovation.
... To understand the energy dynamics of building stock, we develop a model that compares the two major policies of reducing energy consumption in the building sector, that is, through renovation of older buildings and by constructing more energy efficient structures. While comparison of such policies has been done for the developed countries (Alba-Rodríguez et al., 2017;Itard and Klunder, 2007;Power, 2010;Thomsen, 2011;Thomsen and van der Flier, 2009), where most of the building stock needed has already been constructed. There is a lack of such literature for the developing countries, where most of the structures have recently been constructed, are under construction or are planned to be constructed soon. ...
... The most frequently applied changes were changes in heating systems, hot water installations and glazing. Other researchers [12], [13] have discussed whether energy performance measures need to be implemented in small steps or whether large-scale renovations are needed, or whether demolition and new construction are better alternatives. ...
Following regulation of the European Union, objectives were formulated to reduce energy consumption of the built environment in the Netherlands. For the stock of Dutch non-profit housing associations it was agreed to improve the average energy performance to an average energy index of 1.40 in 2020. This research assesses and gives insights in the progress to this objective for over 2.0 million dwellings of over 250 Dutch non-profit housing associations in 2017 and 2018. The assessment consists of an analysis of applied renovation measures, changes of the stock like new construction and demolishing, and clarifying characteristics of housing associations. It is concluded that large urban housing associations with adequate financial positions drive the improvement of the average sectoral energy performance. The improvement happens for a large part within the existing stock, mostly with traditional improvements like improved heating installations and improved insulation. Innovative solutions like: photovoltaic solar systems, combined heat and power systems, biomass systems, heat pumps and external heating, are responsible for a relative small part of the improvement within renovations. New construction and demolishing are also responsible for a relative small part of the annual improvement, but there is potential to improve this.
... In this context, it becomes customary to speak less of the "construction industry," but rather of an "industry of the built environment." The main arguments supporting this transition are that maintaining existing structures contributes to reducing urban sprawl, prolonging the physical service life of buildings and building parts (Thomsen & van der Flier, 2009), promoting waste-avoidance and preserving embodied energy. This specific transition can benefit from the knowledge gained in the field of heritage preservation. ...
The two-year-long efforts of the project consortium resulted in a report, which, basing on particular examples of the evaluation of the impact of cultural heritage on socio-economic sphere, presents the significance of cultural heritage for various aspects of life of Europe’s citizens. For this purpose, project members have developed a holistic four domain approach. An interdisciplinary approach helped embrace a wide spectrum of impact of heritage on our lives, illustrated within four overlapping domains – economy, social and cultural issues, and natural environment. Providing persuasive arguments founded on research results, the report includes also recommendations addressed to policy makers and executive authorities on European, national, and regional level, suggesting a better use of the development potential of cultural heritage.
... To understand the energy dynamics of building stock, we develop a model that compares the two major policies of reducing energy consumption in the building sector, that is, through renovation of older buildings and by constructing more energy efficient structures. While comparison of such policies has been done for the developed countries (Alba-Rodríguez et al., 2017;Itard and Klunder, 2007;Power, 2010;Thomsen, 2011;Thomsen and van der Flier, 2009), where most of the building stock needed has already been constructed. There is a lack of such literature for the developing countries, where most of the structures have recently been constructed, are under construction or are planned to be constructed soon. ...
The dynamic nature of the building stock involving construction, renovation and demolition results in inefficient energy demand creating a huge potential for energy savings. Policy makers have two major tools to reduce energy consumption; by building more efficient structures and through renovating older ones. The reliability of whether an energy efficiency policy can reduce energy consumption in the building sector can be assessed through trial and error in the real world or through computer simulations, which can imitate the dynamics of the real world. This study examines impacts of energy efficiency policies by evaluating the temporal evolution of building sector for the state of Qatar, by using the system dynamic methodology. Qatar has seen a rapid growth in its building sector recently, with the stock growing to twice its size in the past fifteen years. To study the impact of such an increase in the building stock, a system dynamics model is developed with the help of Ventity™ modeling tool, to forecast the combined energy consumption for the 28 building types present in the country. Furthermore, seven energy efficiency policy measures based on renovations and new construction are assessed for these building types to see the impacts on electricity consumption and CO2 emissions. Results show that constructing energy efficient buildings and renovating older ones every 10 years can save more than 4700 GWh of electricity and 2.3 million tonnes of CO2 emissions by the year 2050. More captivating results show that in the long run, constructing new buildings efficiently can save more than twice compared to the most effective renovating policy, ergo demonstrating the need for developing countries to prioritize building efficient stocks rather than renovating older ones.
... In addition to the environmental evaluation, economic aspects are also key factors of the assessment, and tend to tip the balance towards actions of building renovation rather than demolition and new construction. This is due to the increasing value of the building and the quality of its constructive elements [11][12][13]. Other evaluation methods of renovation projects analyzed an economically optimal combination of energy-saving measures, and concluded that the decision for renovation rather than demolition is influenced by the investment cost and the market value of the buildings [14]. ...
Dwelling renovation has gained major importance in the European Union due to the current need for the urban regeneration of many cities, most of whose existing buildings (approximately 60%) were built in the 1960s to 1980s. These renovations require improvements in aspects such as structural integrity, accessibility, and the updating of deteriorated or obsolescent installations. This reveals that building renovations constitute a key factor in the future of the European building sector and must be included in strategies both for the reduction of this sector’s environmental impact and for climate change mitigation. In order to determine the effectiveness of renovations and their impact, the HEREVEA (Huella Ecológica de la Rehabilitacion de Viviendas en Andalucia or Ecological Footprint of the Renovation of Dwellings in Andalusia) model is proposed on data obtained from the project´s bill of quantities, its ecological footprint is assessed, and the economic-environmental feasibility of different proposals are evaluated simultaneously. The resulting model is integrated into a geographic information system, which allows georeferenced results. The tool can be used for sustainable and resilient planning policy-making at all government levels, and for the decision-making processes. In this paper, economic and environmental indicators are, for the first time, simultaneously assessed through statistical normalization obtained from 50 cases analyzed in the city of Seville. Furthermore, five case studies are assessed in detail in order to determine the sensitivity of the model. These renovations represent less than 30% of the cost and 6% of the ecological footprint of a new construction project. During the subsequent 25 years, the energy efficiency improvements could significantly reduce the CO2 emissions that are due to direct consumption.
... The end-of-life phase of a building is characterized by intensive decision-making and organizational activities concerning the building's future Chinda, 2016;Thomsen & Van der Flier, 2009). Buildings are designed for a specified working life, which generally does not exceed 50-60 years (Laefer & Manke, 2008). ...
As the most resource intensive and wasteful industry, the construction sector is causing enormous socio-environmental problems. The root causes of these problems can be traced back to the way building projects are managed. Buildings are generally designed as static structures, but quickly demolished when no longer needed. The concept of a circular economy, alternatively, poses that economic development and profitability are possible without continuously growing pressure on the environment through a combination of reduce, reuse and recycle activities. This thesis therefore aims to develop actionable knowledge on managing circular building projects through exploring how information can be used to reduce, reuse and/or recycle building materials. Each of the chapters examines an essential, information intensive management task that contributes to one or more of these material strategies. The first three chapters do this from a demolition management perspective: they cover information usages for material recovery and reuse decisions (Chapter 1), subsequent coordination of demolition activities (Chapter 2) and the support of those activities with BIM-based methods (Chapter 3). The second three chapters do so from a design management perspective: they deal with information usages in generating reversible design proposals with BIM-based methods (Chapter 4), evaluating those proposals with a virtual reality-based method (Chapter 5) and a reflective serious gaming approach (Chapter 6). Two key management strategies were, accordingly, derived to close material loops. Demolition managers need to use information from previous and later design stages; design managers similarly need to use information from previous and later demolition stages. These a priori and a posteriori information uses provide an actionable response to many of the socio-environmental problems that can be attributed to today’s construction industry.
... Gradual loss of the oldest housing stock, especially the substandard one, looks like a 'natural' process in the growth of a city. It is also explained by a wide range of theoretical concepts, such as, e.g. the concept of burgage cycle (Conzen 1962), the concept of normal (natural) life-span (Harris 1999;James 2012;Thomsen and van der Flier 2009), and the theory of obsolescence (Thomsen and van der Flier 2011). Elimination of old and degraded housing stock may also be part of regeneration as, e.g. an element of the recovery process as a response to 'modernization gap' (Harvey 1989a), implementation (large-scale) of urban development projects (Kazimierczak and Kosmowski 2017;Lehrer and Laidley 2008;Orueta and Fainstein 2008;Turok 1992) or state-led gentrification (Betancur 2002;Smith and DeFilippis 1999;Weber et al. 2006). ...
The paper contributes to the discussion concerning methods used to analyse urban shrinkage and points to the need to comprehensively examine the reasons, course and effects of the process by expanding the research perspective with morphological aspect. In accordance with theoretical assumption adopted for this paper, morphology acts as an element that complements demographic changes in the identification of urban shrinkage since the observed quantitative and qualitative changes in the urban fabric are indicative of the direction of economic and social transformations in cities. The paper aims at identifying the course of shrinkage in a selected post-socialist CEE city and discusses demographic and morphological ways of identifying the process. Łódź (Poland), one of the largest and the fastest shrinking cities in the CEE region was selected for the case study. The paper provides intra-urban scale analyses conducted at the level of individual neighbourhoods taking account of quantitative and qualitative changes in demographic and morphological structure of the city. The picture of changes at a neighbourhood level has helped identify spatial traits of urban shrinkage experienced throughout the city. Spatial scope of the area that undergoes demographic and morphological shrinkage was confronted with the crisis area intended for regeneration within the policy pursued by the city.
... While imposing strict energy requirements for new buildings could resolve the issue for the building stock currently in development, achieving the efficiency goals for the existing building stock in developed countries, presents quite a challenging task. In such countries, the majority of the building stock is older than 40 years (Eurostat, 2010;Kylili et al., 2016) and the rate at which old buildings are progressively replaced by new ones is almost negligible (0.05%e0.1% of the total building stock (Thomsen and Van Der Flier, 2009)). A widely acknowledged mitigation measure is the implementation of large-scale building renovation measures. ...
This interdisciplinary review organizes, summarizes and critically analyzes the literature regarding the nexus between climate change and the built environment, its associated impacts, and the proposed mitigation measures and challenges for their implementation. While global warming-driven changes of ecosystems could have multiple impacts on the built environment (most prominently on building energy demand and related urban energy systems), the building sector presents significant potential for climate change mitigation. Study findings indicate that building renovations have significant potential for the mitigation of urban-related emissions and achieving the sustainability goals set. However, these measures should be adapted to different climate conditions and different segments of the building stock. In developed countries, where the majority of the building stock is older than 50 years, more effort should be invested into creating adequate policies for the renovation of existing building stock. In developing countries with rapid growth in the urban environment, due to a previous lack of energy-efficiency policies, the focus should be on policy development and an increase in environmental awareness among building owners/tenants. Moreover, additional research efforts should be invested into performing technoeconomic and environmental analyses of green wall performance under future climate conditions, especially within the hot and humid climates.
... However, buildings are long-life products (European Commission, 2010;Kelly, 2009) with a low replacement rate for (Thomsen & van der Flier, 2009). It is estimated that four-fifths of buildings in the EU, currently in use will still be operational in 2030 (European Commission, 2010). ...
This report presents a number of business models that have the potential to contribute meaningfully to the energy transition. Building on earlier deliverables, most notably D2.3 Report on novel business models and main barriers in the EU energy system, D5.3 Energy Management Approaches for Sustainable Communities and earlier deliverables D6.1, D6.2 and D6.3 of this work packages this deliverable has sought to both outline the processes that shape our understanding of how business models can be applied to foster change. Each of the 12 business models outlined in this report offer the degree of flexibility and adaptability required for operating within current transitioning frameworks and therefore can be used independently or in combination with other models.
... Demolition refers the end of a building's lifespan caused by man-made destruction (Thomsen and Flier, 2009), whereas adaptation typically refers to retaining part or all of an existing structure (Wilkinson et al., 2014). Adaptation can vary from a change in the ...
Embodied and operational carbon are both an important part of the built environment's impact on climate change. Two mitigation strategies identified for reducing embodied and lifecycle emissions include refurbishing existing buildings or demolishing existing buildings and replacing them with more efficient new buildings. This paper explores existing literature assessing the decision between demolition and adaptation, then through a quantitative analysis assesses three factors regarding lifecycle assessments which were identified through a critique of existing research. The analysis concludes: embodied emissions associated with the existing structure should not be included in decision-making, as they have already been 'spent'; the decarbonisation of the grid is important to consider when comparing strategies, as the cumulative emissions from a less efficient refurbishment are likely to take longer to exceed emissions associated with new build; absolute values for emissions (the total amount for the whole building) should be considered when comparing adaptation to new build projects , since many existing papers focus on emissions per square metre and like-for-like replacements which are deemed to be unrealistic. The quantitative analysis is supported by a qualitative analysis of two focus group with industry and academic experts in the built environment. These focus group discussions showed that there are still methodological issues with life cycle assessments, such as uncertainties with lifespans and data reliability. Participants felt these need to be addressed before legislation and financial incentives can be introduced. A commonly mentioned suggestion to improve the current methodology included collecting more data through case study investigations. Both the qualitative and quantitative analyses build upon the existing research identifying key concepts which need to be addressed and improved upon if considering embodied emissions in the decision to demolish or adapt existing buildings.
... Management of the existing building stock, through intensifying use and prolonging lifespan [1], minimises the magnitude of resource inputs and waste outputs. However, the decision not to prolong lifespan, but instead to demolish, may be taken before the end of a building's physical service life [44,45] for reasons that are outside the control of the construction industry [46][47][48]. Factors that tend to influence this decision, such as land value and rental yield, are not within the present paper's scope. ...
The construction industry uses more resources and produces more waste than any other industrial sector; sustainable development depends on the reduction of both, while providing for a growing global population. The reuse of existing building components could support this goal. However, it is difficult to reclaim components from demolition, and materials remain cheap compared with labour, so new approaches are needed for reuse to be implemented beyond niche projects. This study therefore reviews waste interventions. Multiple case studies, spanning new builds and refurbishment, were undertaken to examine systemic mechanisms that lead to components being discarded. Evidence from fieldwork observations, waste documentation, and interviews indicates that the generators of unwanted components effectively decide their fate, and a failure to identify components in advance, uncertainty over usefulness, the perception of cost and programme risk in reclamation, and the preferential order of the waste hierarchy mean that the decision to discard to waste management goes unchallenged. A triage process is proposed to capture timely information about existing building components to be discarded, make this information visible to a wide community, and determine usefulness by focusing creativity already present in the industry on an exhaustive examination of component reusability and upcyclability.
... Other proposals are more detailed and deal with energy prices, the hypothesis of an increased use of renewable energy, maintenance costs, or financial interest rates (Morelli et al., 2014). However, the need to include not only economic, but also environmental and social aspects in this analysis has increased over time, as these factors are all part of the concept of sustainability (Thomsen and van der Flier, 2009). ...
Since the end of the twentieth century, discussion on dwelling rehabilitation versus its demolition and new construction has been steadily increasing in intensity, which is especially due to the necessity for the regeneration of urban centres. However, rehabilitation is not always considered the most economical solution, and demolition and new construction may constitute a better option. In the present work, a multi-family building in Seville, Spain, is used as a case study. After having suffered damage from a construction failure, it is assessed for its complete rehabilitation. Defective maintenance has worsened the bad condition of the building. A model is proposed, from the project budget perspective, that allows the environmental (Ecological Footprint indicator) and the economic (project's bill of quantities) assessment of the recovery of the dwelling. In the case study, the rehabilitation Ecological Footprint and the project cost are 0.06 gha/m² of floor area (457.22 EUR/m²) and 0.14 gha/m² (576.33 EUR/m²) for a new building on the same plot, respectively. It can be deduced that, even with a severely damaged building, the repair and retrofit work incurs a lower economic and environmental impact than that of the total replacement with a new construction.
... For example, residential buildings in Europe are currently a mixture of different ages and building types: 30 %-40 % were built in the 1945-1970 period and another 20 %-40 % in the 1971-1990 period (Nemry et al. 2010). Annual demolitions ranged from only 0.05 % to 0.2 % of national dwelling stocks in the 1980-2005 period (Thomsen and Van der Flier 2009), resulting in a rapid accumulation of buildings. Studies of specific European countries have shown that the existing material stocks in buildings are quite large and will continue growing slowly, with saturation to be expected in the mid-21 st century (Bergsdal et al. 2007;Müller 2006;Tanikawa and Hashimoto 2009). ...
... For example, residential buildings in Europe are currently a mixture of different ages and building types: 30 %-40 % were built in the 1945-1970 period and another 20 %-40 % in the 1971-1990 period (Nemry et al. 2010). Annual demolitions ranged from only 0.05 % to 0.2 % of national dwelling stocks in the 1980-2005 period (Thomsen and Van der Flier 2009), resulting in a rapid accumulation of buildings. Studies of specific European countries have shown that the existing material stocks in buildings are quite large and will continue growing slowly, with saturation to be expected in the mid-21 st century (Bergsdal et al. 2007;Müller 2006;Tanikawa and Hashimoto 2009). ...
Material stocks
are an important part of the metabolism of society. Due to their long service-lifetimes, these stocks induce long-term dynamics of resource use for their regular reproduction, triggering resource flows during construction, use, maintenance, refurbishment and at the end of their useful lifetime in the form of waste. This chapter explores the material stocks of residential buildings and transportation infrastructure in the EU25 and the way these stocks are related to the overall material consumption of construction minerals. Special focus lies on flows required for maintenance and reproduction versus expansion of the stock. The dynamics of stocks and flows are assessed from a systems perspective on inputs, end-of-life waste and recycling flows in 2009, and a trend scenario for 2020. Thus, we explore the potential impacts of the European Waste Frame-work Directive, which strives for a significant increase in recycling. We find that in the EU25, a large share of material inputs are directed at maintaining and refurbishing existing stocks. Proper management of existing transportation networks and residential buildings is therefore crucial for the size of future material flows. Halting, or at least decelerating, ongoing stock expansion is another promising avenue toward more-sustainable resource use.
... The importance of "adaptable buildings" has been frequently discussed in literature, particularly with regard to various facets of building adaptations, such as "technical and functional performance of adaptable buildings" (Gann and Barlow, 1996;Slaughter, 2001;Kendall, 2003;Larssen and Bjorbery, 2004), "stakeholders' motivation and benefits" (Arge, 2005;Kalita, 2006), "regulations and policies" (Kincaid, 2002;Adeyeye et al., 2010;Ren et al., 2014), "sustainability" (Kincaid, 2000, Thomsen andFlier, 2009) and "risk" (Remoy and Voordt, 2007). Adaptable buildings are defined as "dynamic systems that carry the capacity to accommodate a set of evolving demands regarding space, function, and components" (Adaptable Futures, 2012). ...
Purpose
– The purpose of this paper is to explore the ability of “adaptable buildings” to respond to future potential built environment changes in sustainable way.
Design/methodology/approach
– A detailed literature review and a case study were undertaken to identify the life cycle changes of typical buildings over a period of more than 100 years. In total, 12 semi-structured interviews were conducted among construction industry professionals to identify how adaptable buildings enhance sustainability within the built environment. Case study data were analysed through a Morphological Analysis, and the interview data were analysed through discourse analysis.
Findings
– Out of the many adaptable features, the results revealed “change of use” as the dominant trend within the buildings of the selected urban cluster. More than 60 per cent of buildings have changed their original use during their life cycle. Around 10 per cent of them have changed their use frequently (every six year) during the last 20 years thereby signalling an increase in the rate of change. The positive contribution of adaptable buildings in achieving sustainability in terms of economic, social and environmental considerations, were confirmed through the analysis of semi-structured interviews.
Originality/value
– This paper reports a longitudinal study spanning over 100 years, exploring the extent of building adaptation within a selected cluster of Liverpool city centre, UK. The study further confirms the need to incorporate adaptability as a key criterion when designing buildings. The increased rate at which “change of use” has occurred further reinforces the need. Lack of a track record of designing for reuse makes this an interesting challenge for the construction industry, hence likely to have significant implications for policy/strategy formulation.
... Different types of obsolescence and their combination can lead to the demolition of a specific building. The relation between obsolescence and demolition is, however, complex and has changed over time (Müller, 2006;Pauliuk & Müller, 2014;Sandberg, Sartori, & Brattebø, 2014;Thomsen, Schultmann, & Kohler, 2011;Thomsen & van der Flier, 2009). This paper does not consider obsolescence as a cause but rather as an explanatory variable. ...
Research is presented on the estimation of the lifespan of cohorts of buildings and building stocks. This is based on the analysis of extensive longitudinal data of the 55 000 buildings in the City of Zurich from 1832 and 2010. The survival probability from different perspectives considers age, construction periods, and demolition periods for both existing and demolished buildings. Survival probability is established using a Kaplan–Meier estimator. A more in-depth approach to the mortality of buildings is then determined by differentiating building age, use, size and geographical situation (district). The use of a common geographical information system (GIS) allows longitudinal building data to be linked to a geographical hierarchy of three levels of analysis (city, district and building) accounting for the different granularity on each level (neighbourhoods, quarters, building parts). A comparison of the two methods indicates that the choice of the observed time periods can lead to very different results. The analysis of the three levels shows the possibilities and limits of combined statistical and historical approaches. Mortality analysis is a promising approach to inform policy and practice; it could become a new link between long-term scenario planning, construction policies and institutional regimes.
... End-of-life models are rare (Huuhka & Lahdensivu, 2016). Due to the very low rate of demolition in European housing stocks (between 0.05% and 0.1%), there are few explicit comprehensive mortality models (Thomsen & van der Flier, 2009. When extrapolating simply from the present demolition rate, the average lifespan would be around 1000 years, which is not plausible. ...
What are the patterns and influences on the lifespan of the building stock? This paper presents (1) the reconstitution of an urban building stock composed of more than 60 000 buildings, (2) the analysis of the development of this stock over a period of 180 years (constructions and demolitions), and (3) the analysis of building mortality patterns and reasons for demolition resulting from historic decisions and regimes. A method to reconstitute the stock from different data sources is presented. The mortality models take into account not only the present demolition rates and the age distribution of the ‘survivors' but also the disappeared buildings. The main results are new insights into the lifespan behaviour of buildings according to their period of construction (cohorts) as well as the reasons for demolition. The demolitions do not show specific explanation patterns, but changing influences of the construction activities over time. The average demolition age of all buildings in Zurich, Switzerland, decreased from over 200 years to fewer than 70 years. A total of 18 000 buildings have been demolished over the 180-year period. The presented methods and results can be integrated in multidimensional geographical information systems (GIS) as comprehensive planning, scenario and regulatory tools.
... For those countries where no data was available at all, the annual EU25 average was used (green cells; Table S10). Overall the demolition rates agree well with data presented in the literature (Deilmann et al., 2009;Thomsen and van der Flier, 2009). (Deilmann et al., 2009)For the trend scenario until 2020 the averages of the existing data on demolition and finished dwellings were used (right-most column of Table S9; Table S10). ...
... For example, in the heat domain, there is tremendous technoeconomic inertia in the existing housing stock, which is relatively energy inefficient and poorly insulated, and has a notoriously slow replacement rate (Thomsen and van der Flier, 2009). On the other hand, efficiency improvement of individual housing units, e.g. through whole house retrofits, is a massive challenge in terms of technology, costs, capabilities, and regulatory hurdles (e.g. ...
The paper sets out a proposal for bridging and linking three approaches to the analysis of transitions to sustainable and low-carbon societies: quantitative systems modelling; socio-technical transition analysis; and initiative-based learning. We argue that each of these approaches presents a partial and incomplete picture, which has implications for the quality and usefulness of the insights they can deliver for policy and practice. A framework for bridging these different approaches promises to enrich each of the approaches, while providing the basis for a more robust and complete analysis of sustainable transitions pathways that serves better to address questions and dilemmas faced by decision-makers and practitioners. We elaborate five key challenges for the analysis and governance of transitions pathways, and compare the three approaches in relation to each of these. We suggest an integration strategy based on alignment, bridging, and iteration, arguing that a structured dialogue between practitioners of different approaches is needed. In practical terms, such a dialogue would be organised around three areas of joint knowledge production: defining common analytical or governance problems to be tackled through integration; establishing shared concepts (boundary objects); and establishing operational bridging devices (data and metrics, pathways evaluation and their delivery). Such processes could include experts and societal partners. We draw conclusions about future research perspectives and the role of analysis in transitions governance.
... It is difficult to estimate when the whole building stock will be nearly zero energy buildings. The current service lifetime practice of dwellings in OECD countries can be 100 years [27,28]. Therefore, we suggest that the buildings built before 2020 will be rebuilt/renovated to be nearly zero energy buildings after 100 years of service. ...
If the planet's atmospheric CO2eq concentration is to be limited to 450 ppm by the middle of this century,
what limitation does this place on the size of dwellings and residential buildings energy consumption?
This paper aims to answer and discuss these questions. In the analysis, the world is subdivided into
different regions according to climate and socioeconomic characteristics.We have collected demographic
statistics regarding housing and residential building energy consumption in 31 countries and 14 provinces/
municipalities. Scenarios analyses include energy availability, dwelling size development and
technology expansion. The results indicate that: 1) there is a limitation on dwelling space and energy
consumption within the 450 ppm CO2eq constraint. 2) There is a trade-off on consumptions between
dwelling size and energy. Most regions have a potential to increase dwelling space in the future, if
residents can reduce the residential energy consumption. 3) Zero energy building technology is essential
to reducing residential building energy consumption, especially in the USA, Japan and the emerging
economics. 4) The requirement of zero energy buildings is more urgent in the emerging economies,
especially China and Middle East than the OECD.
The relationship between obsolescence and the rental value of residential properties in Nigeria cannot be overemphasized. The aim of this study is to analyze the effects of obsolescence on the rental values of students' off-campus hostels, in Ifite, Awka. This study investigated the effects of obsolescence on the rental values of students' off-campus hostels in Ifite, Awka Metropolis. The population of study was four hundred and thirty-three (433) comprising one hundred and thirty-three (133) registered Estate Surveyors and Valuers and three hundred caretakers responsible for managing the students' off-campus hostels in Ifite, Awka. A sample size of eighty-one (81) comprising twenty-five (25) registered Estate Surveyors and Valuers and fifty-six (56) caretakers was used and data was collected primarily through a well-structured questionnaire. The study was guided by four research questions and descriptive research design was used. Sample mean analysis was used to analyze the gathered data. The study showed that physical wear and tear, wrong building designs, technological advancements and changes in the economic conditions are the main causes of Obsolescence in Students' Off-Campus Hostels in Ifite, Awka. It also concluded that there is a strong relationship between obsolescence and residential property values and that that rental value is directly related to and affected by the degree of obsolescence seen or observed in a building. The study advocated for improved and efficient maintenance culture and strategies, building designs with flexibility of use to mitigate the rate and effects of obsolescence on buildings.
Anthropogenic stocks are increasingly seen as potential reserves for secondary resources, which has led to a rapid development in research of urban metabolic systems. With regard to buildings and their associated material stocks and flows, one of the most critical shortcomings in the state-of-the-art is the knowledge gap for drivers, dynamics, patterns and linkages that affect the urban metabolism. This paper is premised on the idea that urban planning stirs up these material flows, so it should also adopt their sustainable management on its agenda. It presents an approach that highlights the intertwined nature of changing urban morphology and building material stocks and flows in space and time. An analytical framework, based on the principles of material flow analysis, is provided for an integrated, spatiotemporal study of urban morphology and urban metabolism of buildings, using building and plot data as the input and identifying internal processes of the urban metabolism as the output. The identified processes include greenfield development, infill construction , building replacement and shrinkage, each of which can be expected to have tangible yet very different material and environmental consequences in the form of embodied materials and CO2. The use of the framework is demonstrated with a case study in the Finnish city of Vantaa in 2000-2018. The case study shows patterns pertaining to a growing city unrestricted by geographic or historic factors, manifested as vast greenfield developments and replacement of a notably young building stock. As sustainability may soon call into question both these strategies, uncovering the material consequences of a city's past urban (re)development strategies lay the foundation for using the presented approach proactively in planning support, in pursuit of more circular economy-based and low carbon cities.
Home renovation is an opportunity for decarbonising existing homes, particularly in high home ownership societies such as Australia where renovation is commonplace. Renovation is a socio-technical and emotional people-focused practice, which can take place as a one-off project and as an ongoing activity. Despite growing interest in investigating renovation in line with other everyday practices, recent literature on renovation emphasises defined periods when homes are materially reconstructed. There is limited understanding and documentation of the process before and after this window, specifically the contribution of intermediation and the significance of media in the everyday life at home. The thesis addresses this gap, by investigating the full scope of renovation practice, paying attention to the periods before and after the materially-engaged stages, to explore the significance of household media practices and intermediation in the adoption of low carbon practices. Adopting a practice-theoretical perspective and the mediatisation approach, I carry out an interdisciplinary examination of renovation, joining social research with media and cultural studies and design. I explore renovation practice and its association with homemaking, in a mediatised home environment. I map the complexity of the practice, including the non-materially engaged periods, focusing on the contribution of two different kinds of intermediation: the formal, typically short-term interactions with professionals and the informal, ongoing entanglement of people with media as texts, objects and contexts. Using a focused-ethnography and participatory methodology, I use home-tours and a workshop to bring together the actors that shape the practice. My thesis makes three contributions to renovation scholarship. The first relates to the interdisciplinary understanding of renovation as a practice that extends the materially-engaged periods, spread in five stages (Dreaming/Thinking/Planning/Performing/ Finalising or Sharing). I argue that renovation co-evolves with homemaking, in the mediatised household, and that these two practices get reproduced through common meanings of home, media technologies, emotion, and the tacit, culturally-distinct know-how of householders. This is exemplified through the ongoing Dreaming stage, which 3 connects the materially-engaged stages with the long-term period of imagining and meaning-making of ideal home in the mediatised home. The second contribution is the identification of media (as texts, objects, and contexts) as everyday informal intermediaries, who shape, incubate and accelerate the elements of renovation and homemaking, as meaning-making agents, materials and competences. I argue that the symbolic space of renovation is now global rather than local. The third contribution is the linking of formal and informal intermediation, with different household typologies and the identified renovation stages, examining how these shape low carbon practices. The complexity of the associated practices and the variation of household typologies explain why adoption of low carbon renovation is challenging. Using my stages model, I identify four formal and informal intermediation practices that can assist in the successful embedment of low carbon practices. 4
A reabilitação é uma alternativa sustentável para a construção civil. Porém, verifica-se a existência de poucas literaturas técnicas sobre esta tipologia de obra. Este estudo tem como objetivo levantar e caracterizar manifestações patológicas em edificações públicas que passaram por processos de reabilitação. Foram realizadas inspeções em 8 edificações que passaram por intervenções entre 2018 e 2019. A partir dessas visitas e dos documentos das obras executadas, foram detectados e classificados 4696 pontos de problemas que foram transformados em gráficos para as análises. Detectou-se diversas falhas envolvendo fissurações, umidade e danos aos sistemas. O estudo evidenciou um estado problemático das obras investigadas, podendo servir de referência para melhorias de processos e base para outros estudos.
The Energy Performance of Buildings Directive (EPBD) enhanced the sustainable improvement of dwellings in the European Union. Member states formulated measurable goals to improve the housing stock, and monitoring systems were developed to give insights into the improvements. In the Netherlands, non-profit housing associations agreed to improve the quality of their housing stock to an average Dutch energy label B (energy index (EI NV) = 1.40) by 2020. Research assessing this progress over time is presented using an annual monitoring system based on 2.0 million energy performance calculations of 264 Dutch non-profit housing associations between 2017 and 2020. The assessment includes: a detailed description of the development of the state of the stock over time; the effect of changes to the stock (construction and demolition) and changes within the stock (different types of retrofit measures); and the different characteristics of non-profit housing associations. Insights from this research show which specific retrofit and other measures are adopted and have substantial impact over time. This provides a useful frame of reference for building stock analysis and accelerating the improvement of the building stock. It also creates a baseline of information for the future sustainable development of this particular stock. 'Practice relevance' This research reveals which energy saving measures are most and least employed over time in Dutch non-profit housing associations sector. Large urban housing associations own a large share of the Dutch non-profit housing stock, and their dwellings have on average a lower energy rating. However, the improvement of their dwellings between 2017 and 2020 is higher than for smaller housing associations, which already have on average a higher energy rating. While the construction and demolition of dwellings contribute to 15.6% of the annual improvement, most of the improvement of the energy performance depends on retrofitting the existing stock. The trends are found to rely most on traditional measures ('e.g'. the installation of high-efficiency gas boilers and improved insulation). However, the rate of adding photovoltaic (PV) solar systems has increased rapidly in recent years, while futureproof systems ('e.g'. heat pumps and district heating) only have a steady adoption rate in this sector.
Despite that Building Information Modelling (BIM) is often praised as a whole life-cycle methodology, possibilities for deconstruction are consistently overlooked. This study demonstrates what those possibilities may be. Previous studies showed that: deconstruction practices pose several site-based challenges; BIM implementations may help practitioners to address such challenges; and activity theory offers a framework to understand BIM implementations. We aimed to explore how deconstruction practices can be reorganised with BIM by applying an activity-theoretical perspective to a rather unique case-study. The selected case concerned the deconstruction of a nursing home so that many of its elements could be reused to construct a school. During this project, we implemented BIM in three essential activities: analysing existing conditions, labelling of reusable elements and planning deconstruction. The implementations resolved initial problems related with the use of traditional drawings, schedules and instructions. They nevertheless also triggered several additional problems that we attempted to address in successive steps. The organisation of the activities so evolved, which culminated in the formation of three new BIM uses for deconstruction: “3D existing conditions analysis,” “reusable elements labelling” and “4D deconstruction simulation”. These concepts complement existing BIM use taxonomies and can be appropriated in future deconstruction projects.
The current usage of natural resources cannot be maintained forever – our resources are depleting. A substantial share of resource usage, and therefore the problem, is related to the construction sector. Meanwhile, there are signs that buildings are being demolished prematurely. This premature demolition of buildings is a waste of resources. This dissertation’s end goal is to contribute towards mitigating the problem of resource depletion. Changeability has been selected as the means through which to pursue this goal. This research aims to both understand design and to create support to help improve design, specifically regarding the topic of design for change in relation to sustainable resource usage.
In Chapter 2, i.e. “Resource depletion, where is an intervention most effective?”, the topic of resource depletion is dealt with. Chapter 2’s aim is to rank areas of the resource system, according to how much of an impact can be expected from interventions in the area, in relation to the problem of depleting resources. Firstly, principles of Structured Analysis are used to model the process of resource usage, and, from this model, five intervention areas are defined. Secondly, these intervention areas are ranked in terms of effectiveness, through the use of Analytic Hierarchy Process. To be most effective, one must prioritize intervention areas as follows: (1) material inputs to the operation phase; (2a) process inputs to the operation phase and (2b) products’ longevity; (4) process inputs to the manufacturing phase; and (5) material inputs to the manufacturing phase. In this study, changeability is not pursued for the sake of changeability. Changeability is pursued for the sake of mitigating the problem of resource depletion. Chapter 2’s outcome can guide this pursuit of changeability in the right direction.
In Chapter 3, i.e. “The evolution of ordinary houses, does it justify demolition?”, the topic of longevity in relation to change is dealt with. Chapter 3’s aim is to determine how the ordinary house, in the Netherlands, has changed throughout the last 100 years. This information is then used to discuss: to what extent the house’s evolution justifies demolition. A non-random sampling method is used to select 68 housing projects from the city of Nijmegen. These projects contain a total of 8270 housing units (≈10% of Nijmegen’s housing stock). Of each project, a standard housing unit is analysed in terms of: (1) length and width; (2) floor-to-ceiling height; (3) utilitarian rooms; (4) spatial layout; (5) type of structure; (6) roof structure; (7) insulation; and (8) separating wall’s thickness. Chapter 3’s outcome provides a first indication of to what extent a building’s longevity is determined by its design. This knowledge contributes to a more valid assessment of changeability’s contribution towards mitigating the problem of resource depletion.
In Chapter 4, i.e. “How to set up criteria for evaluating a building’s changeability?”, the topic of changeability is dealt with. In Chapter 4, a method is proposed in which: (1) scenarios are developed to identify potential problems; and (2) evaluation criteria are based on design solutions to those potential problems. To support and guide the development of both scenarios and design solutions, changeability levels and types of design tactics are defined. A top-down approach is used to define changeability levels, while a bottom-up approach, i.e. the constant comparative method, is used to define types of design tactics. This research’s main contribution is that it provides a method for unpacking the black box of design for change. This method is presented in Chapter 4.
In Chapter 5, i.e. “How adjustable is the Environmental Building?”, the application of the evaluation method, that has been presented in Chapter 4, is tested. To do so, the Environmental Building’s adjustability is evaluated by following the steps described in this method. Adjustability is the first of four changeability levels, as defined in Chapter 4. The Environmental Building has the ability to comply with changing requirements of the individual in terms of indoor climate conditions. However, it lacks the ability to comply with changing requirements of the individual in terms of space, privacy and interaction. Chapter 5 demonstrates that by using this method, specific strengths and weaknesses of the building’s design can be identified.
Purpose
Where does one need to intervene in to be most effective? The purpose of this study is to rank areas of the resource system, according to how much of a change can be expected from interventions in an area, in relation to the problem of depleting resources.
Design/methodology/approach
Principles of structured analysis are used to model how society uses resources. From this model, nine intervention areas are defined. These intervention areas are ranked in terms of effectiveness, through the use of the analytic hierarchy process.
Findings
To be most effective, one must prioritize intervention areas as follows: material inputs to the operation phase; process inputs to the operation phase; products’ longevity; process inputs to the manufacturing phase; and material inputs to the manufacturing phase.
Practical implications
Most decisions are not made on the basis of rigorous analysis but by using heuristics (rules of thumb). The results of this study are expressed as rules of thumb. They can help decision makers prioritize what is most important, but without imposing new ways of working.
Originality/value
In the construction domain, heuristics that generalize the impact of actions (content), instead of intervention areas (context), currently seem to prevail. The heuristics of this study generalize the impact of intervention areas. Therefore, they provide an extra perspective for many decision makers. This extra perspective can help reduce mistakes that are typically made by oversimplifying matters.
The goal of this research is to attempt establishing occupant behaviour profiles and how that behaviour impacts energy consumption with regard to indoor comfort levels in the current social housing stock in Turkey. The data consists of a large statistical survey that included four housing complexes situated in different climate regions in Turkey. Another more detailed survey was given to occupants of housing blocks in Ankara. Apartments were also monitored during a one-week period in summer and again in winter. All collected data were evaluated by sensitivity analysis. The results showed that occupant presence at home and operating windows had the most profound effect on internal loads and comfort levels whole year. Additionally, the transparency level of curtains, impacts the indoor temperature during the winter time. The results were used to develop a web-based tool which is going to be a guide for renovation strategies of current housing stock.
Emerging notably in more developed regions, building stock ageing which is characterised by shrinking new completions and falling “mortality” has been posing challenges to various stakeholders in built environment. To find way out of this transition, we need to know how long buildings will last these days and the factors leading to their “mortality”. By using data from 1950s till to date, a comprehensive investigation is conducted to analyse the age composition and life expectancy of public housing stock in Hong Kong. What comes after are survival analysis and empirical analysis of those demolished to identify the key factors leading to demolition. Presented in this paper are the preliminary findings as well as the research agenda on the theme to model age composition and survival of both private and public building stocks in Hong Kong and other similar cities in Asia Pacific Rim such as Adelaide and Singapore, together with research activities to formulate policies for sustainable urban management.
IntroductionClimate change can no longer be ignored. It is globally recognised that the evidence for climate change is unequivocal and that action needs to be taken in order to address its negative effects.These effects, such as warmer and drier summers and more extreme rainfall, may threaten the quality of life of those living in urban environments. To limit these threats, a number of climate change adaptation measures can be taken to pre-empt the negative effects of climate change.The challenge of increasing the implementation of climate change adaptation measures is addressed in this thesis by engaging the construction sector while focusing on the housing stock that is owned and maintained by Dutch housing associations. By implementing climate change adaptation measures, dwellings will become more resilient to some of the effects of climate change, becoming less vulnerable for damage and ensuring the comfort, safety and quality of life of their occupants. Because housing associations are regarded as societal entrepreneurs, these are expected to use resources and commercial profits to achieve societal aims that are in the common interest, such as making timely adaptations, so that changing climatic conditions cannot threaten the quality of their dwellings. Moreover, there are relatively few housing associations compared to the number of houses they own and maintain. In 2012, there were 381 housing associations that owned and maintained a stock of 2.4 million dwellings, representing 32% of the total Dutch housing stock. This means that approaching the Dutch social rented sector was seen as an effective way of generating a greater societal impact.In the past decade, external influences such as the recent economic crisis and political pressure, have led housing associations to become more cost effective and to make changes in their organisational strategies, which has resulted in the adoption of more integrated project delivery methods, such as partnering. These integrated methods aim to involve the construction sector early in the development of plans so that they can contribute their expertise. This creates a more efficient construction and maintenance process and delivers dwellings of higher quality.The housing associations cannot pre-empt all the effects of climate change alone. For adaptation measures at the neighbourhood level, they are dependent on collaboration with other stakeholders such as municipalities, but there are measures that can be applied at the building level, which falls within their range of influence. An example is the application of lighter colours on building façades in order to reflect radiation and reduce the air temperature close to the façades. The hazards of overflowing sewage systems caused by extreme precipitation can be reduced by applying measures to retain water temporarily, such as ‘green roofs’ or to ensure effective drainage such as open pavements. These measures reduce the peak load on the sewage system. Another effective measure is the use of materials that are not negatively affected by water so that if, despite all the precautionary measures, flooding does occur, the consequences would be less severe.Problem formulationThis research assesses the potential of adopting a partnering approach as a governance tool with which to increase the implementation of climate change adaptation measures like those described above. The housing stock owned by Dutch housing associations is taken as a case study. Involving the construction sector through a partnering approach is promising, since construction companies are the ones who carry out the works. Their early commitment reduces the risks of miscommunication or failure and enhances opportunities for innovative solutions. By doing this, not only do housing associations take responsibility for their actions, but the construction sector as a whole gains more responsibility for solving societal challenges and is enabled to co-create solutions that can then be disseminated more easily.The main research question is: How can partnering in construction increase the implementation of climate change adaptation measures in dwellings owned by Dutch housing associations?Research approach and resultsTo formulate an answer to this research question, several separate studies were conducted. First, the characteristics of three types of governance were studied in a literature review, these being hierarchic, market and network governance. Based on these types of governance, many tools have been developed over time, but to increase the implementation of climate change adaptation measures in social housing, not all tools are equally successful, at least not from a theoretical point of view. To improve the implementation of measures, tools could be combined to create a more solid basis for action, and there is room for extra governance tools in the current palette.Based on the literature review on partnering, it was concluded that this could be classified as a combined ‘market’ and ‘network’ type of tool. The market aspect refers to the knowledge of climate change adaptation that is gained by the participating construction companies, which can imply a competitive advantage for them. The network aspect is closely linked to collaboration within a partnering approach. In other contexts, the partnering approach has been shown to remove the barriers of fragmentation in the construction sector; to provide for a more efficient and integral construction process, and to allow for the easier flow of knowledge on climate change adaptation.Next, the current state of knowledge among housing associations was studied with regard to climate change adaptation measures for the housing stock. A content analysis was conducted on the annual reports and policy plans of the 25 largest Dutch housing associations and revealed that they display no awareness of climate change adaptation in their policy documents. As such, they were categorised as ‘unaware’. However, this does not mean that the building stock is not being adapted to climate change, because in the annual reports they state that they have applied climate change adaptation measures, although they do not name these as such. This means that applying adaptation measures is neither impossible nor unrealistic, as long as they are not implemented solely for climate change adaptation purposes, but for other reasons as well, such as energy-efficiency.In contrast to the corporate policy documents, interviews with individual policy-makers showed that housing associations are aware of climate change at a global scale. However, in relation to climate change adaptation measures in their daily work, such as the impact of flooded streets and overheating interiors of dwellings, awareness is low. They could not name many threats or adaptation measures. However, once they had been made aware of the need for such measures, the employees were fairly well capable of assessing them, even though the implementation of measures was evaluated as unfeasible in most cases. The main reason provided was that the housing associations did not have policy guidelines in place for such adaptation measures. Moreover, in many cases there were financial and/or technical barriers that would have to be addressed first. There was a consensus among employees that all the measures would have a positive effect on the comfort of the dwellings.Partnering in construction can help to increase the implementation of adaptation measures because it can overcome many of these challenges. For this reason, the way that housing associations and construction companies carry out refurbishment projects in a partnering approach was also studied. The researcher participated in a knowledge exchange project in which housing associations and construction and maintenance companies had formed dyads and carried out a refurbishment project. They exchanged their experiences on a regular basis through interviews and plenary sessions.In the interviews, employees of housing associations and construction and maintenance companies were asked how they dealt with the success factors for partnering, which were derived from literature. These success factors were trust, leadership, partner capabilities, commitment, conflict resolution, coordination and communication.Although they did not address all these success factors equally well, the study showed that Dutch housing associations and construction and maintenance companies are indeed capable of carrying out housing refurbishment projects in a partnering approach. This allows for the selection of the construction process as a governance tool with which to implement climate change adaptation measures. These measures are considered new products that can be installed with the aim of improving the technical and functional quality of dwellings. In that sense, they are perceived as product innovations, with the dwellings being the ‘products’ and/or assets of the housing associations. This perspective corresponds with the definition1: “[An innovation is] a new idea that is implemented in a construction project with the intention of deriving additional benefits although there might have been associated risks and uncertainties. The new idea may refer to new design, technology, material component or construction method deployed in a project”. Subsequently, the employees of the housing associations and construction and maintenance companies were asked how they dealt with the implementation of innovations using surveys. Although several studies indicate that innovation can benefit when projects are based on an integrated construction process such as partnering, the current study concludes that partnering does not automatically lead to product innovation. Most of the respondents saw partnering itself as the innovative aspect of their projects – i.e. a process innovation. That process innovation required so much attention that there was less emphasis on opportunities for product innovations. This should be taken into account when developing governance tools to encourage the implementation of product innovations in dwellings such as climate change adaptation measures. Moreover, the choice of partnering as a project delivery method as a governance tool is less likely to resolve issues regarding policy, which remain a barrier for the implementation of measures. In addition, other parties can also become involved, to generate resources for the implementation of measures by housing associations. The adoption of partnering as a project delivery method is therefore not the only possible governance tool.To increase the implementation of climate change adaptation measures, two more conceptual approaches were developed by the researcher in addition to the initially hypothesised partnering approach. These additional conceptual approaches involved policy development by housing associations vis-à-vis climate change adaptation measures and collaboration with external actors who face the same challenges in order to enhance efficiency in solving these issues together. The feasibility of the three conceptual approaches was verified by means of a SWOT analysis performed with practitioners from housing associations and construction companies as well as external players such as water authorities, insurance companies and municipalities. The results of the SWOT analysis made it clear that single-pronged conceptual approaches are unlikely to be successful because they involve serious weaknesses or threats. A combination of conceptual approaches is much more likely to remove the barriers that obstruct the implementation of climate change adaptation measures.The conceptual approaches were therefore combined and renamed as implementation strategies. In on-line questionnaires carried out among all Dutch housing associations, it was assessed if the housing associations found it likely that these strategies would indeed lead to the implementation of climate change adaptation measures. In general, the respondents assessed the feasibility of all strategies as unlikely to neutral. There was no strategy that clearly stood out as more feasible for the implementation of climate change adaptation measures. However, a considerable number of housing associations assessed one or more implementation strategies positively and saw opportunities for the implementation of measures, albeit framed differently, such as measures to increase energy-efficiency or enhance comfort.Conclusion
Based on the findings outlined above, the answer to the main research question is: Partnering in construction can increase the implementation of climate change adaptation measures in dwellings owned by housing associations, when it is understood as a catalyst for information-sharing and increased efficiency in the construction process.By looking for shared interests between housing associations and the construction sector, the chances of implementing adaptation measures increase. However, if other stakeholders are involved as well, and if housing associations embed climate change adaptation in their policy guidelines, the likelihood of implementation would increase even more. Although none of the implementation strategies stood out clearly as the strategy most likely to result in the implementation of climate change adaptation measures, a considerable number of housing associations assessed various implementation strategies positively.If the construction process becomes more network-based, which is the case when a partnering approach is adopted, many more parties can become involved and contribute to the implementation of climate change adaptation measures. In such a situation, it no longer matters who introduces the subject during the plan development and construction process, as long as it ends up there and action is taken. To implement these measures more easily, the framing is very important. Climate change adaptation is not enough reason in its own right to begin implementing measures. Insulation to prevent overheating in the summer is considered an ‘extra’ measure - the necessity of which is still questioned by policymakers, for example. However, if the same measure is framed as an energy-saving measure, it is also a cost-cutting measure, which increases the likelihood that policymakers will start making plans to implement it!Scientific implications of the resultsThis thesis has contributed to the development of governance tools to increase the implementation of climate change adaptation measures in dwellings, while current adaptation strategies predominantly target the national or local levels of the built environment. Moreover, this thesis has examined the adoption of partnering as a project delivery method and a governance tool with which to bridge the theoretical fields of network governance and integrated construction and maintenance processes. It extends the palette of governance tools that traditionally consists of information tools, tools relating to the division of property rights, incentives and regulatory tools. It has proven that housing associations can successfully adopt partnering approaches. As such, partnering is a feasible approach by which to increase the implementation of innovative measures such as climate change adaptations.Practical implicationsThe assessment of the five implementation strategies showed that adapting housing for climate change has a low priority as a separate policy field. It is a relatively new area for policymakers, so they may be reluctant to believe that measures are likely to be implemented. Moreover, many other topics may take a higher priority for them, such as improving energy-efficiency and thereby also the affordability of dwellings, and/or preparing the dwellings for an ageing population. In the literature on climate change adaptation, it is suggested that mainstreaming climate change adaptation is the best course, which implies attaching the adaptation policy to existing policy frameworks. This would make policymakers aware of the topic of climate change adaptation and they could look for synergies between measures that were already planned and measures related to climate change adaptations.The refurbishment and maintenance process of housing associations provides opportunities for the mainstreaming of adaptation measures. Housing associations are facing an ageing stock that needs to be improved if it is to continue to meet the ever increasing basic requirements of tenants in terms of quality and comfort and increasingly strict energy-efficiency standards. Since climate change is occurring gradually, there is still time to adapt the building stock gradually, in step with the renovation and maintenance cycles of the housing associations.Bringing in external players, especially municipalities and water authorities, would appear to be a highly feasible approach, given their shared interest in the quality of life in local areas. Bringing together the construction partners requires governance tools that inform them of the benefits of partnering. Particularly if construction companies are to be responsible for the renovation and the maintenance for the rest of the service life of the dwellings, they could focus on improved design solutions that aim to create resilient dwellings, and/or using materials that would be less affected by the effects of climate change. The role of tenants in the implementation of climate change adaptations is primarily that they might exert ‘bottom-up’ pressure by requesting action from housing associations. But for this to happen, they would likely need to be informed about the effects of climate change on their dwellings and/or neighbourhoods, in order for them to be motivated to ensure that their homes are climate change resilient.
TES (Timber based Element System) is targeted at the refurbishment of the European building stock from 1950's to 1980's. The TES sustainability goals are primarily concerned with a holistic approach to energy efficient building refurbishments including TES facade retrofits, employing well managed and cost effective prefabrication methods, and with the ultimate goal to reduce primary energy demand for the operation of a building with the responsible and economical management of resources. Large volumes of material flows result in environmental problems, and TES aims to reduce its' associated environmental impacts.
Acknowledgements:
“smartTES – Innovation in timber construction for the building modernization” is a transnational research project under coordination of the WoodWisdom-Net and funding distributed by national funding agencies.
Duration 2010-2013.
Partners Germany
- Technische Universität München
- Hochschule Rosenheim
- B&O Wohnungswirtschaft
- Gumpp & Maier GmbH
- Ambros GmbH
- Funding: BMBF Finland
- Aalto University
- Finnish Real Estate Federation (Suomen Kiinteistöliitto ry)
- Finnish Wood Research Oy
- Metsä Wood
- Puuinfo Oy
- PAK RAK Oy
- Funding: TEKES
Norway
- SINTEF
- NTNU Norwegian University of Science and Technology
- Funding: The Research Council of Norway
Producing steel causes 6% of global anthropogenic carbon dioxide emissions. Experts recommend that these emissions are reduced by half by the year 2050 in order to avert the worst consequences of climate change. Demand for steel is predicted to double in the next 36 years, meaning that a 75% reduction in emissions per unit of steel produced is necessary to reach the recommended limit. Process efficiency improvements cannot deliver this magnitude of reduction; however if steel is used more efficiently so that less new material is required to deliver the same service - a concept termed 'material efficiency' - then this could allow demand to be satisfied whilst emissions targets are achieved.
Construction is the single largest use of steel globally, therefore using steel more efficiently in construction will reduce emissions. Three material efficiency strategies are identified as having most potential for this industry: using less material, using products for longer, and reusing components. In order to prioritise areas for research, steel flows into construction are mapped, finding that industrial buildings and utility infrastructure are the largest users of steel, while superstructure is confirmed as the main use of steel in a typical building.
To estimate the potential to use less steel in buildings, 23 steel-frame designs are studied, sourced from three leading design consultancies. The utilisation of each element is found and the building datasets are analysed to infer the amount of steel over-provided. The results suggest that such buildings contain almost twice as much steel as necessary for structural performance, and indicate that this amount of over-provision occurs to minimise labour costs, which are a larger proportion of total costs than materials.
To investigate how buildings and infrastructure could be used for longer, reasons for their failure are reviewed. Based on interviews with industry professionals a set of strategies is proposed, tailored to each failure cause and distinguishing between cases where failure can and cannot be reasonably foreseen.
Steel sections could be reclaimed from old buildings and reused in new buildings but this does not occur because they are damaged during demolition. Designing for deconstruction would facilitate reuse but is not practised due to its cost. Data from interviews and a commercial working group are analysed to identify three aspects of designing for deconstruction that provide financial and operational benefits to clients, thus encouraging their use.
One remaining technical barrier to deconstruction is composite steel-concrete systems, where welded connectors make it impractical to separate the steel beam from the concrete slab without damage. A novel bolted composite connector is proposed and tested in three beam experiments. The bolted connector allows successful separation of the components, facilitating reuse. Its structural performance is similar to that of welded connectors and can be predicted using current design standards.
Each of the investigations reveals significant opportunities to reduce steel use in construction by using material more efficiently. Achieving these savings would reduce demand for new steel production and thereby decrease carbon dioxide emissions.
This research explores whether the intrinsic spatial surplus of the post - war, detached dwellings and low-density, dispersed residential neighbourhoods in Flanders, holds potential for transformation in line with con temporary housing standards and demands. This work adopted an architectural approach in order to investigate the feasibility of transformative strategies. Hence, it forms one of three complementary tracks of the FWO funded project Large, Underused Dwellings in Flanders, and is based on typological and design-based research, whereas the other two tracks have respectively studied the shared problem from a geographical and a discursive perspective. This doctoral project has also taken on a second goal which is to frame such design-based enquiry in an academic context. As main source for data gathering throughout the entire project, 10 municipalities across Flanders, with a significant share of detached dwellings, were selected as case studies. About 80% of the Flemish housing stock consists of single family houses, of which 42% are detached dwellings. Many of these were built on spacious lots in a semi-rural or suburban environment during the massive suburbanisation process which was started after the Second World War. The detached dwelling in a semi-rural, green environment has been a key building stone in this process, and is still perceived as the ideal housing situation by many Flemings. The structure of small-scale ownership ensures continuity, and the system facilitates incremental infill of empty lots and retrofitting existing dwellings. This housing model and its mode of production can however be seen as problematical, because they no longer match demographical and socio-economic developments. The ageing population, and the decreasing average household size, result in a demand for other residential typologies: smaller, more compact, and preferably closer to urbanised cores. Moreover, academic researchers, spatial planners an d designers associate the continuation of this mode of spatial production with high emission levels, traffic congestion and loss of open space. Hence there is an emerging interest in, and a need for, alternative models and strategies of transformation. The main body of the work is preceded by an exploration of designerly research, which emerged as a methodology proper to architectural research. Chapter two describes how different approaches to designerly research are used in practice and academia, sharing the goal to address inert and ill-defined problems. A theoretical framework for exchange between scientific and design-based methodologies, allowing the development of transdisciplinary modes of enquiry into ill-defined problems is proposed. Cons equentially, the thesis develops such a process of exchange. Complementary research approaches build on tentative observations and results, and contribute to the understanding of design strategies intervening in the residential environment on different scale levels. The viewpoints of inhabitants of detached dwellings regarding potential adaptive strategies a represented in chapter three. In chapter four, the viewpoints of inhabitants are complemented with a typological analysis of a sample of 65 dwellings documented during field work, in order to determine potential and resistance vis-à-vis transformative concepts on the scale of the dwelling. Chapter five enquires how professional actors involve the detached dwelling and potential design strategies for transformation in their work. A site- and case specific design approach is explored in chapter six, based on a workshop with students in interior architecture and architecture. The workshop investigated plausible conditions and narratives to implement transformative design concepts on the level of the dwelling. The thesis concludes by reviewing these diverse perspectives, addressing the paradoxes and alliances which are exposed, and outlines how these prototypical strategies could impact concrete municipalities. This analysis informs the formulation of three visions on transformation of low density residential environments, combining the strategies of reconfiguration (the retrofitting of existing dwellings) replacement (demolishing existing dwellings and replacing these with alternative dwelling types on site ) and removal (the demolition of dwellings in remote locations followed by densification in more central areas). These visions outline potential evolutions towards differentiation and densification of Flemish residential neighbourhoods.
Like in most EU countries the Dutch housing stock is ageing fast, not just physically but increasingly regarding the functional performance and market position. As the production of new dwellings is generally decreasing to an annual EU average of below 1% of the existing stock, large-scale demolition will be a less obvious option. Combined with the ecologic burden of demolition waste, life cycle extension of existing dwellings will be of growing importance. The useful life cycle of dwell ings can theoretically be defined by their demand accommodating potential that is: to what extend the physical, functional and economical characteristics of dwellings answer the needs and preferences of their tenants. In practice though, the plans and motives of landlords are the true decisive factors. To invest igate the actual demolition practice and underlying decisive factors we started a survey among house owners in the Netherlands. The main questions of this survey were: How many dwellings were demoli shed in the past 5 years, of what type and for what reasons? How many dwellings are planned to be demolished i n the next 10 years, of what type and for what reasons? The paper will present the first res ults of this survey, featuring the social rented stock.
General features of process evaluation
Six broad factors that might influence intervention outcomes
Activities related to refurbishment of the building stock as a percentage of all building work have been constantly growing in most central European countries over the last 20 years. The main argument in this paper is the need to improve knowledge about composition of the existing building stock, the dynamics of its transformation and to relate this to the different actors in property professions. A review is presented of traditional and new sectoral research approaches to partial or national building stocks to provide a context for assessing an integrated approach to the German building stock with methodological propositions for improving the synergy between different sectoral approaches. Detailed consideration is given to life cycle analysis, building product modelling, historical building research and new simulation techniques. Sustainability indicators and the integration of building stock, infrastructure and land use are discussed.
What determines the life span of dwellings? Much is known about the initial phase of buildings. The vast majority of scientific knowledge is concentrated on the building initiative, the programming, design and in particular the construction. Knowledge about the utilization phase, including management, transformation and redesign is growing. But applicable knowledge about the end of life is still scarce. As the housing is ageing and the deliberation between life cycle extension or demolition is getting more and more important, knowledge about demolition, the decisive motives, the pro and cons and the consequences is getting just as necessary as the initial phase. In the last decade we did a series of surveys on demolition in the Netherlands, directed at the social rented as well as the private stock. Based on these surveys we developed a conceptual model of demolition and underlying decisive motives. In search to what extend our findings are also viable in a broader area, we also looked at demolition data in other EU countries and found similarities as well as differences. To initiate a European research cooperation on demolition, our paper explains the relevancy of a Europe wide survey, defines the research objectives, problem definition and main research questions, and proposes a conceptual model and an outline for a broad comparative research.
Uitgegeven in opdracht van de TH Delft, Afdeling Bouwkunde
Sinds de migratiewetten van Ravenstein, die aan het eind van de negentiende eeuw zijn gelanceerd, is er vanuit zeer verschiUende invalshoeken een lawine van verhuistheorieen ontwikkeld. Gebaseerd op een zeer uitvoerige studie van binnenlandse en buitenlandse literatuur wordt een overzicht van deze verhuistheorieen gegeven.
De nadruk wordt hierbij gelegd op de bijdrage die verhuistheorieen kunnen leveren aan het
begrip van woningmarktprocessen en de verbetering van het volkshuisvestingsbeleid. Vandaar de uitvoerige behandeling van doorstromingstheorieen en verhuisketenanalyses.
Tal van essentiele begrippen zoals "woninghierarchie", "woonkarriere", "doorstromingsrendement"
en "housing classes" worden besproken en toegelicht. Een doorwrochte studie, die inzicht biedt in een veelheid van opvattingen en gegevens over de dynamiek van de woningmarkt.
Aanbevolen voor volkshuisvesters en planologen, demografen en sociaal-geografen, sociologen en ekonomen, die zich serieus willen verdiepen in de achtergronden en effekten van verhuisbewegingen.
When undertaking urban renewal projects, decisions must be made between housing maintenance with some minor interventions, and total housing redevelopment entailing the demolition of the existing stock and replacement with new houses. Simple renovations are only possible if the quality of the existing dwelling is sufficient to fulfil current needs. In most urban renewal districts in the Netherlands the existing stock does not meet these current needs. That is why large-scale demolition and the construction of new dwellings are undertaken. However, renovation-based strategies could offer more sustainable alternatives. A comparison of the environmental impacts is made between the renewal options of maintenance, consolidation, transformation, and redevelopment for two typical cases of Dutch urban renewal. The environmental effects are calculated using the Life Cycle Assessment method. Results are presented according to the following environmental effects: the quantities of material, the energy and water used, waste, and environmental impacts. The use of environmental impacts gives a more complete picture than the use of quantities. The transformation of the existing housing stock is found to be a much more environmentally efficient way to achieve the same result than are demolition and rebuilding. The embodied and operational energy use is also compared. Due to the relatively short lifetime of post-war dwellings, the embodied energy can amount to 30% of the total energy use. This means that it is worth using construction methods that reduce embodied energy and designing new buildings so that they are flexible.
According to EC forecasts, if energy efficiency could be increased 1% annually until 2010, two-thirds of the potential energy saving in the EU could be achieved. This would comply with 40% of the EU's Kyoto obligation to reduce greenhouse gas emissions by 8% on the 1990 level by 2010-12, by cutting 200 million tonnes of CO2 emissions per year. Improving energy efficiency in existing buildings is often considered to be one of the most cost-effective ways of cutting carbon emissions. Current policy measures, however, seem to be decided with little reference to the specific needs of renovation in the housing sector instead of basing policy measures on detailed sets of requirements and actual costs. The research provides information for national governments in the EU on how to improve their sustainable building policies so as to increase carbon reductions in the existing housing stock. It addresses the question of the extent to which stronger government intervention is possible and necessary for circumnavigating barriers and the policy approaches that are likely to be feasible, effective, cost-efficient and legitimate.
Although progressive government guidelines and awareness of sustainable issues exists, progress in sustainable management in the social housing sector has been slow. A market research survey and analysis of the sustainable housing management by Dutch housing associations indicates the areas and organizations where policies, instruments and practices are focussed or lacking. Longitudinal trends are established using further surveys from 1993, 1998 and 2000 as well as comparing national strategies from five European Union countries (the Netherlands, Germany, the UK, France and Finland). Results indicate that efforts in sustainable management are misplaced with emphasis on procuring new buildings, not on operation and maintenance. Several barriers at the policy and strategy level are identified, especially the perceived costs of implementing environmental management, the lack of market demand and the poor capture of benefits. Special recommendations for government, housing associations and occupants are based on the findings - widening the focus of issues on sustainability, emphasizing the existing building stock, increasing the use of voluntary agreements, recognizing different capabilities in scale of housing associations and creating market demand.
Technical management is an important policy field for housing associations. Technical management processes influence the product, price, and exploitation characteristics of dwellings. At the higher level the strategic stock policy concerns the complete stock of the housing association. The design of a model relationship between the strategic stock policy and technical management by housing associations features prominently in the research, and common ground is sought between the two areas. Important points attended to in the study are the relationships between strategic stock policy, (de)investment policy, maintenance policy, and rental price policy; the relationships between investments, maintenance activities, performance levels, defects, life cycles and exploitation period; and the relationships between policy development, provision of information, organization, and management.
By deriving the technical management from the strategic stock policy, the housing association can carry out maintenance and adaptations efficiently and effectively -- in other words in a professional, client-centred, sustainable manner. The likelihood of loss of capital is reduced. Product characteristics and maintenance performance levels can be adjusted to suit the target groups and clients served. Clients appreciate having more freedom of choice in the maintenance and adaptation of the (interior of their) dwellings, and set requirements with respect to maintenance work: information, approachability, client friendly attitudes, orderliness, and so forth. Through the mutual harmonisation of policy, the foundations of policy can be made clear and transparent for all parties concerned within and outside the organization. Thereby, opportunities are enhanced for controlling processes, costs and performance and contracting out parts of the management process in a responsible manner. The housing associations can concentrate on their core tasks and the planning and control of the technical management process.
Demolition of private housing stock in the Netherlands, volume and motives. Paper presented at the ENHR Conference
- A Thomsen
- K Van Der Flier
Thomsen, A. and van der Flier, K. (2007) Demolition of private
housing stock in the Netherlands, volume and motives.
Paper presented at the ENHR Conference 2007, Rotterdam,
The Netherlands.
Changes in the Dwelling Stock
- Cbs
- Statline
CBS Statline (2008b) Changes in the Dwelling Stock (available at: http://statline.cbs.nl).
Sustainable housing trans-formation; quality and improvement strategies of the ageing private housing stock in the Netherlands. Paper presented at the ENHR Conference
- A Thomsen
- F Meijer
Thomsen, A. and Meijer, F. (2007) Sustainable housing trans-formation; quality and improvement strategies of the ageing private housing stock in the Netherlands. Paper presented at the ENHR Conference 2007, Rotterdam, The Netherlands.
The Ecology of Tomorrow's World The World Summit on Sustainable Development
- J Elkington
Elkington, J. (1980) The Ecology of Tomorrow's World, Associ-ated Business Press, London. European Commission (2002) The World Summit on Sustainable Development; People, Planet, Prosperity, European Union, Luxembourg.
Demolition of social dwellings: volume, plans and motives. Paper pre-sented at the ENHR Conference
- A Thomsen
- M T And Andeweg Van Battum
Thomsen, A. and Andeweg van Battum M.T. (2004) Demolition of social dwellings: volume, plans and motives. Paper pre-sented at the ENHR Conference 2004, Cambridge, UK.
The Future of Sustainability: Re-thinking Environment and Development in the Twenty-first Century Environmentally Sustainable Buildings: Sus-tainable Use of Building Stock
- W M Adams
- Iucn
- Gland
- D A Anink
- J P Mak
- Milieuvisie
- W Zuid
- Gouda
- H Awano
Adams, W.M. (2006) The Future of Sustainability: Re-thinking Environment and Development in the Twenty-first Century, IUCN, Gland. Anink, D.A. and Mak, J.P. (2005) Milieuvisie Moerwijk Zuid, W/E adviseurs, Gouda. Awano, H. (2003) Environmentally Sustainable Buildings: Sus-tainable Use of Building Stock, OECD, Paris. Bekkers, H. (1976) Het keuzeprobleem bij woningverbetering, DUP, Delft. CBS Statline (2008a) Residential Buildings by Region (available at: http://statline.cbs.nl).
De invloed van levensduur op de milieueffecten van een woning Bouwen met tijd, SEV, The Hague
- J Kortman
- H Van Ewijk
Kortman, J. and van Ewijk, H. (2004) De invloed van levensduur op de milieueffecten van een woning, in J. Hoogers (ed.): Bouwen met tijd, SEV, The Hague. Lö nberg-Holm, K. and Larson, C.T. (1953) Development Index, University of Michigan, Ann Arbor.
Eco-Quantum; Development of LCA Based Tools for Buildings, IVAM
- J Mak
Mak, J. et al. (1997) Eco-Quantum; Development of LCA Based
Tools for Buildings, IVAM, Amsterdam.
Real Estate Development Principles and Process De kwaliteit van de Nederlandse woning en woonomgeving rond de milenniumwisseling; Basisrappor-tage Kwalitatieve Woningregistratie 2000, MVROM, The Hague. NCCW (1993) Handleiding BRON – Beslissingsmodel renova-tie
- M E Miles
- R L J Haney
- G Berens
Miles, M.E., Haney, R.L.J. and Berens, G. (1996) Real Estate Development Principles and Process, Urban Land Institute (ULI), Washington, DC. MVROM (2003) De kwaliteit van de Nederlandse woning en woonomgeving rond de milenniumwisseling; Basisrappor-tage Kwalitatieve Woningregistratie 2000, MVROM, The Hague. NCCW (1993) Handleiding BRON – Beslissingsmodel renova-tie, Onderhoud of Nieuwbouw, NCCW, Almere. OECD (2004) OECD/IEA Joint Workshop on Sustainable Buildings: Towards Sustainable Use of Building Stock, OECD, Paris. Priemus, H. (1984) Verhuistheorieë en de verdeling van de woningvoorraad, DUP, Delft. Snel, K. (1987) Sloop, een reë alternatief, NWR, Almere.
The new building assignment: old stock, new markets. Paper presented at the Erabuild Event
- A Thomsen
Thomsen, A. (2007) The new building assignment: old stock,
new markets. Paper presented at the Erabuild Event 2007,
TU Delft, Amsterdam, The Netherlands, 29 -30 October
2007.
Milieuvisie Moerwijk Zuid
- D A Anink
- J P Mak
Anink, D.A. & Mak, J.P., (2005). Milieuvisie Moerwijk Zuid, Gouda (W/E adviseurs).
The Eco-costs of housing transformation Sustainable neighbourhood transformation
- T De Jonge
De Jonge, T. (2006). The Eco-costs of housing transformation. In: V Gruis, H Visscher &
R Kleinhans (Eds.), Sustainable neighbourhood transformation. Amsterdam (IOS
Press).
Environmental impacts of renovation. The Dutch housing stock compared with new construction Sustainable neighbourhood transformation
- L C M Itard
- G Klunder
- H J Visscher
Itard, L.C.M, Klunder, G. & Visscher, H.J. (2006). Environmental impacts of renovation.
The Dutch housing stock compared with new construction. In: V Gruis, H Visscher
& R Kleinhans (Eds.), Sustainable neighbourhood transformation. Amsterdam
(IOS Press).
De invloed van levensduur op de milieueffecten van een woning
- J Kortman
- H Van Ewijk
Kortman, J. and van Ewijk, H. (2004) De invloed van levensduur
op de milieueffecten van een woning, in J. Hoogers (ed.):
Bouwen met tijd, SEV, The Hague.
De kwaliteit van de Nederlandse woning en woonomgeving rond de milenniumwisseling
MVROM (2003). De kwaliteit van de Nederlandse woning en woonomgeving rond de
milenniumwisseling; Basisrapportage Kwalitatieve Woningregistratie 2000, Den
Haag.
Sloop en sloopmotieven, tussenrapportage enquête sociale huursector
- A Thomsen
- M T Andeweg Van Battum
Thomsen, A. & Andeweg van Battum, M.T. (2004), Sloop en sloopmotieven,
tussenrapportage enquête sociale huursector. Delft (TU Delft).
The new building assignment: Old stock, new markets. Erabuild Event
- A Thomsen
Thomsen, A. (2007), The new building assignment: Old stock, new markets. Erabuild
Event 2007, 29-30 October 2007, Amsterdam (TU Delft).
Matching alternatives, Design & Decision Support Systems for the management of existing housing stock, paper for the Int
- K Van Der Flier
- A Thomsen
Van der Flier, K., & Thomsen, A. (1996), Matching alternatives, Design & Decision
Support Systems for the management of existing housing stock, paper for the Int.
Conference on Design & Decision Support Systems in Architecture and Urban
Planning, Spa (TU Eindhoven).
Het keuzeprobleem bij woningverbetering
- H Bekkers
Bekkers, H. (1976) Het keuzeprobleem bij woningverbetering,
DUP, Delft.
Sectorbeeld Woningcorporaties verslagjaar
CFV (2007) Sectorbeeld Woningcorporaties verslagjaar 2006,
CBS, Voorburg.
The eco-costs of housing transformation
- T De Jonge
De Jonge, T. (2006) The eco-costs of housing transformation, in
V. Gruis, H. Visscher and R. Kleinhans (eds): Sustainable
Neighbourhood Transformation, IOS Press, Amsterdam.
The World Summit on Sustainable Development
European Commission (2002) The World Summit on Sustainable
Development; People, Planet, Prosperity, European Union,
Luxembourg.
Real Estate Development Principles and Process
- M E Miles
- R L J Haney
- G Berens
Miles, M.E., Haney, R.L.J. and Berens, G. (1996) Real Estate
Development Principles and Process, Urban Land Institute
(ULI), Washington, DC.
De kwaliteit van de Nederlandse woning en woonomgeving rond de milenniumwisseling; Basisrapportage Kwalitatieve Woningregistratie
- Mvrom
MVROM (2003) De kwaliteit van de Nederlandse woning en
woonomgeving rond de milenniumwisseling; Basisrapportage Kwalitatieve Woningregistratie 2000, MVROM, The
Hague.
Handleiding BRON -Beslissingsmodel renovatie
NCCW (1993) Handleiding BRON -Beslissingsmodel renovatie, Onderhoud of Nieuwbouw, NCCW, Almere.
OECD (2004) OECD/IEA Joint Workshop on Sustainable
Buildings: Towards Sustainable Use of Building Stock,
OECD, Paris.
Sustainable housing transformation; quality and improvement strategies of the ageing private housing stock in the Netherlands
- A Thomsen
- F Meijer
Thomsen, A. and Meijer, F. (2007) Sustainable housing transformation; quality and improvement strategies of the
ageing private housing stock in the Netherlands. Paper
presented at the ENHR Conference 2007, Rotterdam, The
Netherlands.
Systematische benadering van de levensduur van onroerend goed
- H Vroman
Vroman, H. (1982) Systematische benadering van de levensduur
van onroerend goed. Misset Beheer en Onderhoud, 96, 10.