Home energy efficiency and radon: An observational study

Exposure to radon gas is the second leading cause of lung cancer worldwide behind smoking. Changing the energy characteristics of a dwelling can influence both its thermal and ventilative properties, which can affect indoor air quality. This study uses radon measurements made in 470 689 UK homes between 1980 and 2015, linked to dwelling information contained within the Home Energy Efficiency Database (HEED). The linked dataset, the largest of its kind, was used to analyze the association of housing and energy performance characteristics with indoor radon concentrations in the UK. The findings show that energy efficiency measures that increase the airtightness of properties are observed to have an adverse association with indoor radon levels. Homes with double glazing installed had radon measurements with a significantly higher geometric mean, 67% (95% CI: 44, 89) greater than those without a recorded fabric retrofit. Those with loft insulation (47%, 95% CI: 26, 69) and wall insulation (32%, 95% CI: 11, 53) were also found to have higher radon readings. Improving the energy performance of the UK's housing stock is vital in meeting carbon emission reduction targets. However, compromising indoor air quality must be avoided through careful assessment and implementation practices.     

Appropriate energy efficient building envelope technologies for social housing in the Irish climate

Extensive dynamic thermal simulation parametric analyses have been undertaken of energy efficient fabric alterations to social housing in Northern Ireland culminating in priorities for deployment. Five ȁ8basecaseȁ9 simulation models were used to represent the predominant characteristics of the existing social housing stock. The majority of technologies studied provided annual space-heating energy savings of more than 10%. The variation of energy savings and economic performance across the basecases highlights the value of a dwelling specific approach to selecting energy efficient building envelope technology solutions for energy rehabilitation programmes. The paper further outlines a framework for prioritising appropriate energy efficient building envelope technological solutions for a large regional building stock, i.e. existing social housing stock in Northern Ireland, highlighting influential parameters. An energy efficient building envelope inter-technology ranking approach provides a method of comparison across the various different dwellings in the regional housing stock. Airtightness ranked consistently highest across the dwellings studied with some solar technologies performing better than more technologically mature solutions such as insulation.     

Whole life costing of domestic energy demand reduction technologies: householder perspectives

A recent, major UK research project investigated technical and social aspects of reducing the CO₂ emissions of UK domestic housing by 50% by the year 2030. As 80% of the UK housing stock that will be present in 2030 has already been built, this study aimed to research the whole life costs of three sets of energy demand reduction technologies for existing housing, over a 25‐year period, suitable to deliver significant CO₂ emissions reduction up to 50%. Demand side technological interventions in the form of fabric upgrades and ventilation systems are identified. Whole life cycle analysis of interventions carried out on two housing variants prominent in the domestic stock under different energy price scenarios is carried out using discounted cash flow and compared with the do‐nothing option. The results show that, despite reducing annual energy bills, there is no clear financial case even over a 25‐year horizon for householders to invest in the proposed interventions that contribute to CO₂ emission reduction targets. When discussed with respect to household income and consumption preferences, the results reveal the need for new policy approaches to overcome the financial and non‐financial hurdles for a mass uptake of energy efficient technologies.     

Feasibility of zero carbon homes in England by 2016: A house builder's perspective

The UK government set itself a 60% reduction of carbon dioxide emissions target on 2000 levels by 2050. This commitment will require carbon reductions to be made by all industries including the housing sector which presently accounts for 27% of carbon dioxide emissions. The house building industry is the subject of numerous government policies and legislation, but none are as demanding as the Code of Sustainable Homes, which set a ‘world-beating’ target for all new homes to be zero carbon by 2016. This paper sets out to investigate the feasibility of building zero carbon homes in England by 2016 from a house builder's perspective. A comprehensive opinion of the feasibility of zero carbon homes is gathered through a questionnaire survey and in-depth semi-structured interviews with the major UK housing developers. The research found that there are currently numerous legislative, cultural, financial and technical barriers facing house builders to deliver zero carbon homes in England by 2016. The house builders surveyed concurred that these challenges are not insurmountable provided that a swift, all-embracing and above all realistic strategy is adopted and implemented across the supply chain.     

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.     

城市能源系统改造模拟方法：泰恩河畔纽卡斯尔的当前实践和未来挑战

文章回顾了英国的碳减排议程和当前地方在构建城市能源模型方面的实践与挑战,提出了技术与社会系统相互作用下的模型研究与定量理解中存在的一些缺陷。文章还梳理了对家居行为和能源需求已有的模型方法,以便将研究重点（反弹效应和需求侧管理）以及研究采用的行为模型的基本原理纳入整体研究框架。该模型模拟和量化了技术系统的改造和家居行为之间相互作用中的两个突出部分——反弹效应和需求侧管理。利用这一模型,文章详细阐释了对泰恩河畔纽卡斯尔200套社会住宅的案例研究,研究结果对于旧城改造的规划决策系统建设具有重要的理论与现实意义。     

An embodied carbon and energy analysis of modern methods of construction in housing: A case study using a lifecycle assessment framework

There is a growing interest in comparing the energy and consequential carbon embodied in buildings using different methods of construction and alternative materials. This paper compares the embodied carbon in a low energy, affordable house constructed using a novel offsite panellised modular timber frame system, in Norfolk UK with two traditional alternative scenarios. A lifecycle assessment (LCA) framework is used to conduct a partial LCA, from cradle to site, of the construction. An inventory of the materials and fossil fuel energy utilised in the construction was used to calculate the primary energy consumed and the associated embodied carbon. The embodied carbon was found to be 34.6 tonnes CO₂ for a 3 bedroom semi-detached house, 405 kgCO₂ per m² of useable floor area. When compared with traditional methods of construction the modern methods of construction (MMC) house resulted in a 34% reduction in embodied carbon. Despite timber being the predominant structural and cladding material, concrete is the most significant material (by proportion) in embodied carbon terms, responsible for 36% of materials related embodied carbon.     

The Supply-Side Modernisation of Social Housing in England: Analysing Mechanics,Trends and Consequences

The past 30 years have seen England's housing associations (HAs) transformed from marginal players in the wider housing market to a point where, in 2008, they overtook local authorities as majority social housing providers. This paper reviews theoretical perspectives on the evolution of the UK social housing and the rise of HAs since the 1970s, with a particular focus on the ‘modernisation’ thesis advanced by Malpass & Victory (2010). Against this backdrop, we analyse the sector's recent reconfiguration, integrating the impacts of housing stock transfers and HA mergers. Our analysis focuses on the consequences of sector restructuring in terms of organisational homogenisation and, at least as perceived, the growing dominance of giant landlords. Finally, within the context of the Coalition Government's localism rhetoric, we discuss the accountability implications of restructuring activity and the light our analysis sheds on theoretical understandings of social housing change processes.     

Supply and Demand for Low Energy Housing in the UK: Insights from a Science and Technology Studies Approach

Economic theory about supply and demand suggests that if consumer demand for a product increases then producers respond by increasing supply. In the UK housing market there is emerging evidence of consumer demand for low energy housing, yet little has been built to date by private sector housebuilders: existing low energy housing is largely within the social housing and self-build sectors. Ideas from science and technology studies (STS) are introduced to help further understanding of why the housing market might be slow to respond to changing consumer preferences. Although standard economic concepts concerning costs and price are able in part to explain the situation, greater attention to socio-technical issues highlights some of the reasons why innovation and change are difficult to effect. The housing market is best viewed as a socio-technical system, whereby the social and the technical are interlinked.     

新型预制复合墙板农居结构热工性能试验研究

为研究四川大学预制住宅课题组提出的新型预制复合墙板住宅体系下的农村住宅围护结构的保温隔热性能,通过模型试验方法对新型预制复合墙板农居结构的热工性能进行了测试分析研究;并将其传热系数的试验结果与理论计算值进行了对比分析。研究结果表明:采用200 mm厚的新型预制复合墙板能够使农村住宅满足夏热冬冷地区农村居住建筑的节能标准和要求;增加混凝土层或保温层厚度可进一步提高热惰性指标和降低传热系数,从而使新型预制复合墙板达到更好的保温隔热效果。     

An environmental assessment of wood and steel reinforced concrete housing construction

Wooden type of housing is ubiquitous in Japan. It is the main structure for housing; however, due to the increase in residential developments, steel reinforced concrete houses are also on the rise. This paper assesses the environmental impacts of these two types of construction. An evaluation of the two types of construction in terms of energy usage and air emissions is done. A comparison of the damage costs due to the generated emissions is also considered. Four types of emissions generated are evaluated, namely carbon emissions (CO₂), nitrogen oxides (NO_x), sulfur oxides (SO_x) and suspended particulate matter (SPM). The life cycle of the two different housing construction types is traced and environmental impacts are determined. External costs are also calculated. Furthermore, different improvement assessment scenarios are simulated to ascertain several emission reduction possibilities. The study looks into the emitted emissions from the housing construction to its final disposal of a typical residential development in Saga, Japan. Results show that much of the environmental impacts from building a house are on the Global Warming Potential due to high carbon emissions. Moreover, the construction phase generated the highest pollutant emissions from nitrogen oxides, sulfur oxides and suspended particulate matter. Steel reinforced concrete (SRC) construction has a higher environmental impact compared to the wooden type of housing construction. A longer design life for a residential house gives a reduction of about 14% in carbon emissions. Using solar energy for the operation phase has gained a reduction of 73% in the total life cycle carbon emissions.     

Housing Abandonment in Inner Cities-The Politics of Low Demand for Housing

Abandonment of property in all housing tenures is a problem in some British inner cities, especially in the north of England. The paper outlines the causes of this phenomenon and describes some of the social problems that arise in areas containing significant quantities of abandoned property. A principal underlying cause of abandonment is low demand creating, initially, voids and vacancies in the dwelling stock and ultimately housing abandonment. The paper considers the relationship between empty stock and abandonment particularly in the social housing sector. It reviews the US and UK literature and concludes that the UK literature and research agenda is deficient in its analysis of the problem of abandonment. The paper then explores evidence of the source of the abandonment problem in the low demand for housing in some parts of the country, particularly those affected by industrial collapse. Abandonment is also explained as a case of policy failure particularly due to the housing subsidy system and the conflicting interests of central and local government. Finally, the social consequences for communities afflicted by low demand and abandonment are explored and evidence is presented of the severe impact on neighbourhood stability.     

Brick and mortar treatment by cream emulsion for improved water repellence and thermal insulation

A novel polymer cream was applied to brick and mortar in an attempt to reduce water absorption and to improve thermal insulation for household heating energy saving. Tests were carried out on surface energy, water contact angle, thermal conductivity and sorptivity of brick and mortar with and without cream treatment. A model house was built and a heating and monitoring system was developed to quantitatively evaluate the heating energy consumption in different conditions before and after cream treatment. It was found out that cream treatment can successfully impart good water repellence and enhanced the thermal insulation of the brick and mortar. The results from contact angle and surface energy measurements showed that the materials became highly hydrophobic. Experimental results from the model house showed approximately 9% heating energy consumption reduction in dry conditions and approximately 50% in wet conditions. In addition, the internal humidity typically was reduced to almost 1/3 of that of the control. It has been demonstrated that the novel cream treatment on masonry buildings can help reduce damp problems and save household heating energy consumption which can make a significant contribution to addressing social, environmental, ecological and economic problems resulting from climate change and global warming.     

Ventilation strategies for urban housing: lessons from a PoE case study

Mechanical ventilation with heat recovery is still not widely used in UK housing, but with insulation and air-tightness standards becoming increasingly strict, it is likely to become more common. Operable windows are almost a given for housing and the UK climate is rarely extreme enough to restrict people's use of those windows for natural ventilation. This is a potential problem for the use of heat-recovery systems and could greatly reduce their energy efficiency. The paper takes the Iroko housing scheme at Coin Street, London, as a post-occupancy evaluation (PoE) case study to investigate the questions raised with respect to how well the occupants of the houses cope with balancing both natural ventilation and mechanical systems to achieve thermal comfort energy efficiently. First, the optimum balance of mechanical and natural ventilation is estimated and used to determine the maximum potential saving it could give when compared with natural ventilation alone. Short-term monitoring of the building in question together with the results of questionnaires showed why this theoretical balance is not achieved and that the energy consumption is likely to be worse than for natural ventilation alone. Noise, perceived control, perceived freshness and misunderstanding are all discussed as possible causes for the apparent disjunction. Misunderstanding on the part of residents was shown to be a critical determinant, so information about the heat recovery system was distributed to the residents and the paper ends by looking at what theoretical energy savings might be made as a result of this act.     

Analysis of retrofit air source heat pump performance: Results from detailed simulations and comparison to field trial data

In the UK, gas boilers are the predominant energy source for heating in housing, due primarily to the ready availability of natural gas. The take-up of heat pumps has lagged far behind Europe and North America. However, with the development of standards for low and zero-carbon housing, gas price rises and the depletion of the UK's natural gas reserves, interest in heat pump technology is growing. Heat pumps, particularly air source heat pumps (ASHPs), have the potential to be a direct, low-carbon replacement for gas boiler systems in housing.In this paper, monitored data and simulations were used to assess the performance of an ASHP when retrofitted into a dwelling. This required the development and calibration of a model of an ASHP device and its integration into a whole-building, dynamic simulation tool. The predictions of the whole-building model were compared to field trial data, indicating that it provided a suitable test bed for energy performance assessment. Annual simulations indicated that the ASHP produced 12% less carbon that an equivalent condensing gas boiler system, but was around 10% more expensive to run. However, the proposed UK renewable heat incentive transforms this situation, with income from ASHP heat generation exceeding the fuel costs.     

廉租房——城镇住房弱势群体救助的现实选择

针对城镇住房弱势群体而展开探讨,在分析其现有住房保障政策的基础上得出了推行廉租房制度的结论。进而剖析了试点中的廉租房制度存在制度、资金、对象、数量、信息等方面的不规范,重点阐述了完善廉租房制度的对策措施。它们是：制定助人自助的救助战略;达到强弱“共生发展”的认识高度;形成稳定规范的保障资金来源;共同发挥存量、增量房源的有效作用;建立部门明确分工、各司其职的廉租房管理体制;建立从廉租房申请到监控的一整套制度;采取实物配租和租金补贴的廉租方式;完善廉租房配套政策,健全住房保障。     

Towards global benchmarking for sustainable homes: an international comparison of the energy performance of housing

Over the past 15 years, house building standards across the western world have begun to address ecologically sustainable development (ESD) principles. Amongst the range of environmental sustainability issues arising from housing construction and occupation, the energy demand for heating and/or cooling to maintain thermal comfort has the longest history and is most widespread in policy and regulation. Since energy in our homes is mainly fossil-derived, a key issue is global climate change impacts. Since greenhouse gas emissions can be emitted in various locations across the globe with similar results, it follows that a given greenhouse gas emission arising from residential space heating and cooling has approximately equal impact, irrespective of the location of the building. These emissions are therefore an appropriate candidate for benchmarking internationally, yet there have been few attempts to undertake this activity. This paper reports on a study undertaken in Australia which compares the thermal energy performance of housing in the United States, Canada, UK and Australia. The comparison is based on energy ratings of over 50 house designs from the comparison countries. Each design was assessed as being current and verified as complying with rather than significantly exceeding local regulatory requirements. Issues in design of both the buildings and the modelling tool used are highlighted, and the results are presented. Conclusions are drawn on the reasons for wide variations in thermal energy performance, the implications for benchmarking, and the case for globally consistent housing environmental performance policies and regulation.     

基于BIM的住宅项目策划系统研究与开发

本文针对住宅项目策划的实际需求,综合应用BIM和4D技术,研究并提出了基于既有标准户型的住宅方案BIM建模和方案分析与评价的方法。通过解决户型三维模型与各种经济及绿色性能指标信息的关联、存储、编辑与管理,基于户型组装生成住宅标准层和建筑单体方案,以及基于经济指标与绿色性能分析进行方案评价等关键技术,以Autodesk Revit 2012和清华大学4D项目管理系统为平台,开发了基于BIM的住宅项目策划系统。应用表明,本研究为住宅项目策划的方案创建、分析评价、比选决策提供了新的途径和方法,促进了BIM在住宅项目策划阶段的应用。     

荷兰社会住宅的可持续更新——以罗森达尔“被动房”住宅项目为例

文章简述了荷兰可持续社会住宅的基本情况和欧洲“被动房”建筑的相关概念,并介绍了荷兰罗森达尔的一个社会住宅更新项目。该项目运用“被动房”建筑的理念和技术对原有住宅进行更新改造,从而大大降低建筑的能耗,实现了社会住宅的环境可持续性目标。     

Green roofs; building energy savings and the potential for retrofit

Green roofs are a passive cooling technique that stop incoming solar radiation from reaching the building structure below. Many studies have been conducted over the past 10 years to consider the potential building energy benefits of green roofs and shown that they can offer benefits in winter heating reduction as well as summer cooling.This paper reviews the current literature and highlights the situations in which the greatest building energy savings can be made. Older buildings with poor existing insulation are deemed to benefit most from a green roof as current building regulations require such high levels of insulation that green roofs are seen to hardly affect annual building energy consumption.As over half of the existing UK building stock was built before any roof insulation was required, it is older buildings that will benefit most from green roofs. The case for retrofitting existing buildings is therefore reviewed and it is found there is strong potential for green roof retrofit in the UK.