Development of a model to estimate the benefit‐cost ratio performance of housing

A simulation model based on classical population dynamics is developed to estimate the benefit‐cost ratio performance of different typologies of housing with the purpose of identifying potential reductions in the total costs and hence resources used to sustain housing. A typical New Zealand dwelling constructed of lightweight timber framing is used as an example. Dwellings within the simulation model undergo periodic cycles of refurbishment based on best practices. When the simulated housing stock expands at the rate of 1.5% per year, an annual expenditure equivalent to the costs to construct one dwelling sustains the services provided by 26.7 dwellings after adjustment for economic depreciation. This benefit‐cost ratio performance improves by 32.4% when the housing stock is stationary. Further improvements of 5.3% can be achieved by deferring refurbishment and accepting a higher level of economic depreciation of dwelling services. The results of all scenarios indicate that structural systems with a service life of only 50 years should not be used unless the costs of such systems are substantially less than the costs of traditional structural systems and that lightweight timber framed dwellings should not be sustained well beyond a service life of 90 years.     

Energy and mass flows of housing: a model and example

The energy and mass flows required to sustain dwelling services can be established and quantified only within the framework of a stock and flow model of the total housing stock. This paper develops such a model to estimate the energy flows of a typical sub-population of New Zealand housing stock. The energy and mass flows of key building materials are estimated and the energy flows of alternative cladding systems are compared. The stock and flow model is driven by empirical schedules of mortality. A guide to estimating the mortality of housing stock is set out in the companion paper (Johnstone IM. Energy and mass flows of housing: estimating mortality. Building and Environment 2000;36(1):43–51).     

Life cycle analysis of housing

This paper reports the findings of a project to assess the costs and benefits of adopting environment‐friendly construction practices for social rented housing in Scotland. Two contrasted dwelling specifications — one for a conventional building (the Control) and one for an environmentally responsible building (Eco‐Type 1) — are compared using Life Cycle Analysis and Life Cycle Costing methodologies. An assessment is made of the environmental and economic implications of adopting environmentally conscious construction practices in social rented housing. It is concluded that the provision of environmentally responsible dwellings could bring large‐scale reductions in the environmental burden of housing, and economic savings for housing providers and tenants over the life cycle of a dwelling with only a small increase in capital costs.     

Energy and mass flows of housing: estimating mortality

Stock and flow models of housing should be driven by empirical schedules of mortality. A selection of analytic, life table, and stock and flow models used to estimate the mortality of housing are examined. The assumptions which underpin each of these models, data difficulties, issues of validation and misapplication of mortality indicators are addressed. A stock and flow model is used to estimate the energy and mass flows required to sustain dwelling services in the companion paper (Johnstone IM. Energy and mass flows of housing: a model and example. Building and Environment 2000;36(1):27–41).     

Service management in housing refurbishment: a theoretical approach

It is unusual to find that housing refurbishment projects have been undertaken with a clear focus on customer orientation directed towards the tenants, or owners of cooperative flats or condominiums. Only recently have researchers in construction management begun to look closer at the relationship between contractors and customers. To assess the scope for customer orientation in the refurbishment industry, current thinking in service management is reviewed here in an attempt to identify principles with implications for housing refurbishment. There is a consensus among service management investigators that services are intangible; other often mentioned characteristics are heterogeneity, perishability, and the inseparability of production and consumption. Except for inseparability these characteristics are valid for refurbishment. Nevertheless, features such as the long turn-round time, the number of participants, the complexity and the uncertainty, distinguish housing refurbishment from most services. There is strong empirical support for the claim that customer satisfaction increases customer loyalty and gives the service producer a positive reputation, ultimately increasing profitability. It is concluded that this insight can be interpreted operationally for housing refurbishment projects, bearing in mind that the tenant or the owner of a cooperative flat is the customer's customer.     

A hierarchical Bayesian framework for calibrating micro-level models with macro-level data

Owners of housing stocks require reliable and flexible tools to assess the impact of retrofits technologies. Bottom-up engineering-based housing stock models can help to serve such a function. These models require calibrating, using micro-level energy measurements at the building level, to improve model accuracy; however, the only publicly available data for the UK housing stock is at the macro-level, at the district, urban, or national scale. This paper outlines a method for using macro-level data to calibrate micro-level models. A hierarchical framework is proposed, utilizing a combination of regression analysis and Bayesian inference. The result is a Bayesian regression method that generates estimates of the average energy use for different dwelling types whilst quantifying uncertainty in both the empirical data and the generated energy estimates. Finally, the Bayesian regression method is validated and the use of the hierarchical Bayesian calibration framework is demonstrated.     

关于小城镇住宅建设的研究

介绍了当前我国小城镇住宅建设现状,对目前我国小城镇住宅区规划与建设中存在的问题与不足进行了分析研究,根据我国的国情探讨了解决小城镇住宅规划与建设的思路和措施,以促进我国住宅建设的可持续发展。     

无锡地区安置房小户型研究

城市建设用地的扩张带来了城市外围用地性质的变更,大量农民从集体土地上的自建住宅搬迁到安置小区。文章针对在置换过程中,在农民安置住宅设计与使用中出现的Diverse question提出相应的设计变通策略,在符合国家政策、规范的前提下对安置户型的可适性、变通性、舒适性做些有益的研究。     

British home owners and housing change in rural France

Drawing on a survey of 406 home owners in France, expansion in British property ownership is shown to have increased the rural housing stock and to have improved rural housing quality. In all, 30 per cent of British home owners in France have added at least one dwelling to the housing stock, mostly by restoring a derelict property or bringing an unwanted farm building into residential use. Amongst other property owners, 55 per cent have undertaken significant renovations (extensions, major structural work, etc.), so more than two‐thirds of all British buyers have helped raise the quality of the rural housing stock. This has had little effect on house prices, partly because there is little French demand for the properties Britons buy. Given that British buyers are also reluctant to acquire homes from other Britons, a semi‐autonomous housing market is being created in which resales are difficult. This tendency is weakening slightly now, but British owners who wish to sell continue to rely on France being used as an extension of ‘British’ rural housing markets, wherein they can acquire a rural ‘dream’ home that is not only unaffordable but also unattainable in Britain.     

Low carbon housing refurbishment challenges and incentives: Architects’ perspectives

The UK has a legally binding commitment to reduce CO₂ levels by 80% by 2050 relative to the 1990 emissions baseline. The existing housing stock, which accounts for approximately 30% of total UK energy demand, has the potential to provide significant opportunities for this reduction; however, currently there are no legislative measures driving widespread low carbon housing refurbishment (LCHR) design and construction. Architects have a decisive role to move forward the LCHR agenda owing to their leadership and significant involvement in the initial briefing, conceptual and design development phases of a project, regardless of project procurement types and project sizes. Hence, the aim of this research is to investigate the key challenges and incentives for achieving LCHR in England from architects’ perspectives.     

A Building System for Housing

The present national policy, as set forth by President Johnson in a recent housing message, calls for a national goal of 26 million new housing units during the next 10 years. This rate is 10 times the housing replacement rate of the last 10 years. Added to this, there are over 30 million Americans presently living in some 10 million dwelling units which are rated as substandard by any of the numerous housing and/or building codes which exist in this country today.     

Dynamic-MFA examination of Chilean housing stock: long-term changes and earthquake damage

The dynamics and metabolism of the built environment are important for understanding the construction, renovation and demolition activities that characterize its long-term physical development. Previous research on building stock development is limited, particularly for developing countries. As one of the most seismically active countries in the world, Chile's built environment is constantly subjected to losses. This study included earthquake vulnerability and damage in a dynamic material flow analysis (MFA) of the Chilean housing stock. Stock and flows of residential floor area were modelled using population and life style parameters. Demolition was modelled assuming a constant demolition rate. By characterizing the building stock according to vulnerability classes and establishing a mass balance per class, the effects of different typology distributions on the overall damage to the stock caused by earthquakes could be assessed. Scenarios with different trends in typology distribution for new construction and renovation suggest that significant potential exists for reducing future earthquake damage in the Chilean housing stock. This is best achieved by gradually reducing the vulnerability of buildings to earthquakes. Legislation, building standards and financial instruments could be used to ensure such reductions in earthquake damage and thereby provide socio-economic benefits in the future.     

Obstacles and opportunities for reducing dwelling size to shrink the environmental footprint of housing: tenants’ residential preferences and housing choice

The environmental footprint of housing is greatly influenced by the size of a dwelling. Housing size is the result of households’ dwelling selections; accordingly, it is critical to consider residential preferences and choices to inform efforts towards housing sustainability. This study aimed to understand tenants’ preferences for and choices of housing size as one amongst several dwelling characteristics and identify obstacles and opportunities for reducing size in the light of promoting sustainable housing. We employed logistic regression models to analyse a survey with 878 Swiss tenants, and our results identify preference for large dwellings as a major obstacle for reducing dwelling size among affluent tenants. Conversely, tenants with lower income might be forced to move to a smaller dwelling due to financial constraints or attribute higher importance to the financial benefit of lower rents. However, financial disincentives along with substantial non-monetary costs of moving, such as the disruption of local bonds and the difficulty of finding a satisfactory dwelling, can outweigh the benefits of moving to a smaller dwelling. To overcome such obstacles, we suggest offering incentives and other facilitating measures for downsizing moves as well as ensuring an adequate supply of smaller dwellings capable of providing high living quality. We highlight the potential of studying housing functions to conceptualize dwellings fulfilling these requirements.

     

国际大规模增量住房的建设与实践

大规模增量住房是一种由公共部门和个体家庭共同承担建设成本与社区责任的经济适用居住模式。以逻辑 组织理论为指导，将增量住房划分为自下而上的自组织增量住房和自上而下的他组织增量住房，分别通过印度尼 西亚雅加达的甘榜和秘鲁利马的巴里亚达斯两个案例剖析了两种类型的优点和缺点。最后以哥伦比亚波哥大的巴 楚城为例，将其建设过程分解为由公共部门决策的住区结构规划、用地布局规划和“场地与服务”建设三个阶段， 以及由个体家庭决策的规划增量与未规划增量建设两个阶段，旨在证明双重组织的大规模增量住房是一种兼顾经 济性和公平性的可持续住房供给模式，对实现土地紧凑利用、家庭按需建设和成本持续投入等具有重要意义。     

From renting to owning: Life course and housing market circumstances

Moving from a rental dwelling to owner occupation is an important event in the housing career of a household. The literature shows that considerations of housing consumption, related to household circumstances, play a dominant role in the decision to rent or to buy a dwelling. The analysis in this article substantiates again that family status must have reached a certain stability, and prospects of a substantial permanent income must be good, before the move from renting to owning is considered. But general economic circumstances which manifest themselves into changes in housing market conditions, also have measurable influences on the decision for renting or owning. In the Netherlands, the propensity for renters to buy a dwelling were low between 1978 and 1982 when prices of owner occupation were falling, mortgage interest rate was high and income prospects were uncertain. Government policy certainly has an influence on the decision of households to rent or to buy a dwelling. In the long term government promotion of one particular tenure sector over a long period may well stimulate household preference for this sector. And by consistently building large parts of new construction in one tenure, opportunities of moving in or into this sector are increased as this article illustrates for Randstad Holland.     

Homogenous homes of Finland: ‘standard’ flats in non-standardized blocks

Several authors have successfully created and employed vintage cohorts and housing typologies in research addressing energy renovation needs in the existing dwelling stock. This paper suggests that the idea of types would be useful in creating living quality-related renovation and adaptation concepts for homes. These concepts could be used for increasing the accessibility and individuality of flats and easing life in cramped conditions by means of design. Therefore, the study tests the approach by examining the plan design of flats in one cohort: the Finnish 1960–80s' dwelling stock. A total of 320 apartment blocks with 8745 flats in 51 cities are examined. The study identifies 18 different types of flats, which are based on 10 basic layouts, representing over 80% of all flats. Although the housing production of this era was characterized by cost-efficiency and industrialized prefabrication technologies, the result can be deemed somewhat surprising. This is because the building layouts were never standardized in Finland: only the production technology was standardized. The identified flat types are estimated to cover as much as one-third of all existing Finnish flats. These findings provide future opportunities for creating new mass-tailored renovation concepts.     

Housing refurbishment contractors selection based on a hybrid fuzzy-QFD approach

With low demand for new construction, limited land usage, and being aware of sustainability, the refurbishment market has grown greatly and has become more in demand in the construction industry. Most refurbishment work, however, involves a high level of risk, uncertainty, and coordination, which are likely to cause asymmetric information between contractors and residents in a refurbishment process. Most private refurbishment contractor selections are usually based on word-of-mouth referrals that lack a systematic and objective assessment method. This study proposes a hybrid approach combining fuzzy set theory and quality function deployment (QFD) to establish a housing refurbishment contractor selection model. With this model, residents can select an optimal refurbishment contractor according to requirements. To test the effectiveness of the proposed model, a known multiple criteria decision-making method, PROMETHEE, is applied to compare the results of contractor selections. The result reveals that the proposed hybrid fuzzy-QFD approach can be expected to be successful and has potential for handling multiple criteria decision-making problems.     

Does Social Capital Affect Residents' Propensity to Move from Restructured Neighbourhoods?

Many Dutch post-war neighbourhoods are subject to intensive urban restructuring. Demolition and new housing construction combined with social and economic programmes should improve the housing stock, liveability and social capital. Currently, it is unknown whether social capital contributes to residential stability and reduces residents' propensity to move. In this paper, social capital levels of stayers, movers and newcomers are studied in two recently restructured neighbourhoods in Rotterdam, The Netherlands. Using survey data, social capital is operationalised as benefits of everyday cursory interactions, trust, shared norms and collective action. Logistic regression analysis shows that age, length of residency, employment, income, dwelling satisfaction, dwelling type and perceived neighbourhood quality significantly predict residents' propensity to move. Newcomers are more inclined to move again than stayers and other movers. Social capital is of less importance than suggested by previous research; housing features, satisfaction and neighbourhood perception affect residents' propensity to move much more strongly. The paper concludes with policy implications and suggestions for future research.     

Displaced but still Moving Upwards in the Housing Career? Implications of Forced Residential Relocation in the Netherlands

The housing stock is being restructured in many Dutch post-war neighbourhoods. Through demolition and upgrading of social rented housing and the construction of new owner occupied dwellings, the housing stock and the living environment are being improved. This policy has triggered major residential moves in and beyond some neighbourhoods, partly involuntary. Residents whose dwelling is being demolished or heavily upgraded, are usually forced to move elsewhere. Knowledge of the social implications of forced relocation in the Netherlands is limited, especially on experiences and opinions of relocated households. This paper covers research in two recently restructured neighbourhoods. Movers were recruited to share their experiences and opinions in focus groups and interviews. Surprisingly, many movers were able to improve their housing situation, mostly due to their priority rights in the housing market. However, movers who were less able to take advantage of these rights reported a certain degree of degradation. Moreover, it appears that relocation processes must still be improved in order to reduce stress and refine communication with residents.     

GA-based decision support system for housing condition assessment and refurbishment strategies

Refurbishment work involves improvement, upgrading, renovation, retrofit, and repair of existing housing. With limited land usage and being aware of sustainability, the refurbishment market has faced increasing needs worldwide. During the long life cycle period of housing, most residents are undoubtedly faced with refurbishment requirements. However, it is not easy to make assessment and refurbishment related decisions due to the lack of knowledge and experience. This study presents Genetic algorithm-based on-line decision support system (DSS) to help residents easily conduct the housing condition assessment and offers optimal refurbishment actions considering the trade-off between cost and quality. Two refurbishment models are developed to explore the relationship among the life cycle cost, restoration cost and improved quality. The result reveals the proposed DSS solves the problems arising from asymmetric information and conflicting interests between residents and contractors, as well as improves traditional housing condition assessment to be more effective and efficient.