Optimizing tradeoffs among housing sustainability objectives

The sustainability of housing units can be improved by integrating green building equipment and systems such as energy-efficient HVAC systems, building envelopes, water heaters, appliances, and water-efficient fixtures. The use of these green building measures often improves the environmental and social performances of housing units; however they can increase their initial cost and life cycle cost. This paper presents a multi-objective optimization model that is capable of optimizing housing design and construction decisions in order to generate optimal/near-optimal tradeoffs among the three sustainability objectives of maximizing the operational environmental performance of housing units, maximizing the social quality of life for their residents, and minimizing their life cycle cost. The model is designed as a multi-objective genetic algorithm to provide the capability of optimizing multiple housing objectives and criteria that include minimizing carbon footprint and water usage during housing operational phase, maximizing thermal comfort, enhancing indoor air and lighting quality, improving neighborhood quality, and minimizing life cycle cost. An application example is analyzed to illustrate the use of the developed model and evaluate its performance. The results of this analysis illustrate the novel capabilities of the model in generating 210 near-optimal tradeoff solutions for the analyzed housing example, where each represents an optimal/near-optimal and unique tradeoff among the aforementioned three sustainability optimization objectives of maximizing the operational environmental performance of housing units, maximizing the social quality of life for their residents, and minimizing their life cycle cost. These novel capabilities of the developed model are expected to improve the design and construction of housing units and maximize their overall sustainability.     

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.     

Optimising renovation strategies for energy conservation in housing

A method for developing an optimal energy strategy for housing refurbishment, specifically applied to high rise, multi-family blocks, is considered. The ‘BREDEM 8’ monthly calculation procedure was used to compare the effect of various refurbishment measures on a flat in a typical housing block. The performances of insulating measures, glazing options, control of ventilation and alternative heating systems were considered. A life cycle costing method was used to assess and compare their performances, to give an indication of financial benefits over the life of the measures. The ‘savings-to-investment ratio’ was used as a ranking tool, and a process for selecting measures, applying them to the building, and re-calculating the cost effectiveness of the remaining measures enabled interaction between the retrofits to be considered.     

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.     

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.     

叠合板式工业化住宅的经济性研究

针对叠合板式工业化住宅和传统现浇混凝土住宅,从构件工程量及含量指标、主要构件的综合单价组成等方面比较两种结构的差异性,继而定量计算、比较分部分项工程项目和单价措施项目成本,并定性比较总价措施项目成本,明确叠合板式工业化住宅存在建造成本较高的不足。在此基础上,从全生命周期角度出发,论证叠合板式工业化住宅通过延长使用周期、降低运营费用降低全生命周期成本的特点,以此揭示叠合板式工业化住宅的经济性。     

节能住宅全寿命期经济效益及实证分析

以节能住宅全寿命期费用分析为基础,构建其全寿命期经济效益评价模型,并以重庆地区某节能住宅为实例进行计算,通过分析其全寿命期所取得的良好经济效益,加深消费者对节能住宅的认同,从而促进节能住宅的推广。     

Periodic refurbishment and reductions in national costs to sustain dwelling services

This paper uses a simulation model to make exploratory estimates of current and potential reductions in national costs to sustain dwelling services due to refurbishment. Data and parameters are based on a typical New Zealand dwelling of lightweight timber framed construction. Dwelling service years provided by a dwelling over one year adjusted for depreciation serve as a proxy for benefits. The costs to construct one dwelling and fractions thereof serve as a proxy for the costs of maintenance, refurbishment, replacement, and new construction. Current levels of refurbishment reduce national average costs to sustain dwelling services by a magnitude of 15%. Potential reductions in national costs are modest (5%) should the housing stock be stationary, but are negligible when the expansion rate of the housing stock is as high as 2.0% per year. A decline in the expansion rate of a housing stock has a greater impact on reducing national costs than an increase in the number of cycles of refurbishment.     

Decision Support System for Waterproofing of Below-Grade Structures

Abstract:   This study focused on the development of a decision support system (DSS) for waterproofing of below-grade structures. The objective was to formulate an optimal solution for waterproofing of below-grade structures according to their parameters and based upon engineering and economic criteria. The model examines the environmental, structural, economic, and service life planning aspects of waterproofing in an integrated manner. The decision support model was based on the following four phases: input interface, preliminary classification, advanced classification, and output interface. The output phase consists of an interactive accessory that provides design details and quality assurance guidelines for each particular case, as well as economic parameters such as life cycle costs and risk of failure. The major contribution of this DSS is its development of a methodological application of integrated decision process, achieved by the use of engineering, economic, and service life criteria. Application of the DSS to several case studies revealed that a number of near-optimal alternatives exist, which differ from one another in terms of constructability, capital costs, and labor inputs. Cost of failure plays a major role in life cycle assessment, and may be a salient factor in the selection of the optimal solution.     

住房开发中应导入功能经济思想

住房开发中同样要强调功能经济思想,这对我国住宅产业健康发展有着重要的意义。目前我国住房开发存在着功能过剩、功能与成本严重不匹配和不计全寿命期成本等背离功能经济的现象。文章中指出住房开发中必须导入功能经济思想。导入的途径包括住房产品设计、企业转变经营哲学及政府政策引导与监管等。     

Multifamily housing and resident life satisfaction in Europe: an exploratory analysis

Much of the literature on sustainable communities and compact cities calls for higher density housing including multifamily dwellings. Some researchers suggest problems with such dwellings. However, rigorous comparative research on this topic has not been conducted to date. This paper draws on a high quality, comparative data-set, the European Social Survey, to analyse (a) the quality of multifamily dwellings in European urban areas, (b) the characteristics of residents, (c) their life satisfaction compared with those living in detached housing and (d) the relative importance of built form in explaining life satisfaction. One of the main findings from the multivariate analyses is that residing in multifamily housing is not a statistically significant predictor of life satisfaction when you control for standard predictors of life satisfaction and housing and neighbourhood quality. Overall, the findings provide support for both place-based and people-based responses to urban regeneration. Both physical and social regeneration are required, addressing the education/training needs of residents and economic development strategies.     

论房建施工质量的控制措施

房建工程的施工质量是与住户的生命财产安全息息相关,但目前房建工程存在质量问题,对人们的生命财产安全造成了不同的危害。为了提高房建工程的施工质量,文章分析了控制施工质量的要点,并提出了有效的解决措施。     

Differences in quality of life estimates using rents and home values

Quality of life differences across areas can be measured by differences in “real wages,” where real wages are computed as nominal wages adjusted for the cost of living. Computing cost of living differences involves several important issues, including how housing prices should be measured. Previous researchers typically have used some combination of rental payments and homeowner housing values, but housing values are forward-looking and may not reflect current user costs. This paper examines differences in quality of life estimates for US metropolitan areas using, alternatively, rents and housing values. We find that the two measures of quality of life are highly correlated. Value-based estimates, however, are considerably more dispersed than rent-based estimates, likely because of the recent housing bubble and because housing values often provide an imperfect measure of the present user cost of housing.     

全生命周期费用管理对生态住宅的启示

工程项目的全生命周期费用管理是实现项目建设前期、建设期、运营维护期和拆除期等各阶段总费用最小化的一种理论和方法。绿色生态住宅,就意味着要投入更多更全面的新材料和新技术,这样势必会提高工程造价和开发成本,本文试用工程项目的全生命周期理论来探讨生态住宅的价值问题。     

保温墙模复合剪力墙体系全寿命周期成本分析

对新型建筑节能体系——保温墙模复合剪力墙体系进行全寿命周期成本分析。根据节能建筑实际建立住宅全寿命周期成本计算数学模型,运用该模型进行住宅的经济效果综合评价。经济性综合评价结果表明:该体系的全寿命周期成本显著低于普通剪力墙体系及砖混结构体系。体系在提高住宅适用性、安全性、耐久性、舒适性等住宅品质的同时,还带来了显著的经济效益。     

Learning from St. Thomas: Community,Capital, and the Redevelopment of Public Housing in New Orleans

Current efforts to redevelop public housing in the US create new opportunities and risks for low-income residents. Although cities are able to pursue innovative strategies for combatting troubled public housing, the danger is that the interests of the residents will be subordinated to those of the local power structure—especially where public housing poses an obstacle to revitalization. This article examines the efforts to redevelop the St. Thomas Housing Development in New Orleans in order to discover the impact on residents and to evaluate prevailing theories of urban power. The case involves empowered public housing residents and powerful economic interests. Although residents of St. Thomas gained access to the pro-growth coalition pursuing revitalization of the surrounding Lower Garden District, the outcome for residents is mixed. In order to understand the constraints faced by public housing residents we must recognize how political discourse can enhance the power of the business community in urban regimes.     

从"为大众的住宅"到"为大众的社区"从"居住区规划"到"社区建设"

在历经20年的建设后，中国的城市住房在数量和质量方面都有了飞跃发展，但同时，城市的富裕居民和贫困居民在住房条件上的鸿沟也日益加大。有鉴于美国在住房建设方面的经验，文章提出应制定一种侧重于社会发展的住房新政策，并提出“为大众的社区”和“社区建设”的概念。     

绿色建筑部品全生命周期成本与效益评价方法研究

提出全生命周期成本效益评价方法包括费用效益法和费用估算方法,以及这些方法的使用范围和使用现状。根据全生命周期评价理论与建筑部品全生命周期阶段划分,重点研究绿色建筑部品全生命周期评价技术路线,以及绿色建筑部品全生命周期各阶段成本与效益评价方法。得出科学的绿色建筑部品全生命周期成本和效益的评价方法有利于促进绿色建筑事业的长远健康发展。     

浅析高层房建工程给排水施工技术

本文就当前高层房建工程排水施工技术进行了探讨,通过对排水技术的重点以及相应的排水施工技术的分析,为加强房建工程质量,改善居民居住环境以及生活质量提供了一些技术参考。     

Romancing the high-rise in Singapore

Since the 1960s, Singapore has continually built high-rise buildings to house its growing population. While many other developing cities are faced with a housing shortage, the greater proportion of the Singapore resident population is living in and owning accommodation in high-rise buildings. Drawing on interviews conducted with public housing families in their homes, this paper seeks to discuss and provide a perspective of the Singapore residents’ attitude to high-rise living. Although the discussion is focused on the Singapore resident perspective, high-rise living experience is not unique to Singapore. If international building and urbanization trends are any indication, more and more urban residents will have the opportunity to live in high-rise housing. A widening number of cities, including London, are building 50-story housing as the latest answer to their country’s housing shortages. Given the extensive high-rise living in Singapore, the findings of this paper stand to offer important implications to cities considering high-rise housing.