Achieving a sustainable urban environment: working with existing buildings

ACHIEVING A SUSTAINABLE URBAN ENVIRONMENT: WORKING WITH EXISTING BUILDINGS Keith Jones University of Greenwich Derek Clements-Croome University of Reading AbuBakr Bahaj University of Southampton David Gann Imperial College, London Abstract Achieving the goal of sustainable development continues to be one of the major global challenges of our era. To date the vast majority of work has focused on improving the sustainability of the design and construction phases of the building life cycle. Whilst the outputs from this work are beginning to have an effect on the sustainability of new buildings, because of the legacy of the existing building stock, it is unlikely that it will produce a sustainable urban environment in the short to medium term. In reality only a small percentage of the worlds built environment is replaced each year, over the next 20 years much of the built environment will comprise that which already exists or is in the planning stage. If the built environment is to address the changing needs of society in a more sustainable manner, then the construction industry will have to work largely with buildings that already exist. Thus the challenge facing built environment professionals working at the post construction phase of the building life cycle is to find ways of improving the sustainable performance of existing built facilities. This paper will examine these challenges and will outline a major new research initiative underway in the UK to address the issues pertinent to achieving a sustainable urban environment through the maintenance and refurbishment of the existing building stock. Keywords: Building Façade; Building Maintenance; Sustainability. INTRODUCTION The sustainability debate has come a long way since the energy crisis of the 1970’s first focussed world attention on the profligate manner with which humankind was consuming the Earth’s natural resources. Brundtland (1987) produced a definition of sustainable development as that which “…meets the needs of the present without compromising the ability of future generations to meet their own needs…’ and this has focussed much of the thinking about sustainability over the past 15 years. The debate was broadened in 1992 at the United Nations Rio Earth Summit where Agenda 21 (UN Department of Economic & Social Affairs 1992) was formulated as guidance for those working towards a more sustainable future and again at Kyoto (UN Framework Convention on Climate Change 1997) where the impact of climate change was considered and then at Johannesburg (UN World Summit on Sustainable Development, 2002) where obstacles to the implementation of Agenda 21were examined and a new way forward proposed. In 1999 the UK Government (DETR, 1999) produced its strategy for sustainable development which identified four aims: social progress which recognises the needs of everyone; effective protection of the environment; prudent use of natural resources; and maintenance of high and stable levels of economic growth. 103 In 2000 the UK Government released a second report ‘Building a better quality of life – a strategy for sustainable construction’ (DETR, 2000) which identified the role that the construction industry could play in improving the collective quality of life of UK citizens. The report identified 10 action areas for the industry to take account of: the reuse of existing built assets; designing for minimum waste; aiming for lean construction; minimising energy in construction; minimising energy in use; reducing pollution; preserving and enhancing bio-diversity; conserving water resources; having respect for people and their local environment; and setting targets to monitor performance and to better manage/reduce the impact of buildings on the environment. In 2001 a further report by the UK Built Environment and Transportation Foresight Panel, Constructing the Future (DTI 2001) examined the future needs of the UK’s built environment and drew attention to the fact that as only a small percentage of it is replaced each year, over the next 20 years, much of the built environment will comprise that which already exists or is in the planning stage. If this is indeed the case then, if the UK’s built environment is to address the changing needs of society in a more sustainable manner, the construction industry will have to work largely with buildings that already exist. In its summary the Foresight Report made a number of recommendations including: the promotion of ‘smart’ buildings and infrastructure; improvements in the health and safety of those employed in the construction industry; enabling supply chain integration; investing in people; improving existing built facilities; exploiting global competitiveness; embracing sustainability; increasing investment returns; and the need to plan ahead. In addition to the recommendations the report also outlined the changing demands that would be placed on the built environment (population demographics, knowledge based working practices, climate change etc) and suggested specific actions around whole life thinking and the use of advanced technology, materials and processes which would be needed to address them. Indeed, with respect to the improvement of existing built facilities the report called for the development of innovative processes, technologies and components for the maintenance, repair and refurbishment of the built assets identifying in particular the potential for new technologies and ‘intelligent’ products to improve living and working environments and enable information feedback to improve construction quality. It is against the above that a new UK based multi-disciplinary research consortium in the Design Construction and Operation of Buildings for People (IDCOP) was developed. The IDCOP consortium is led by a management committee drawn from the University of Greenwich, the University of Reading, Southampton University, Imperial College, London and Ove Arup. The remainder of this paper will outline the work of the consortium as it relates to existing buildings. AIMS OF THE IDCOP CONSORTIUM Work on developing the IDCOP consortium began in November 2001, when a number of academics and industry representatives attended a 2 day workshop hosted by the Engineering and Physical Sciences Research Council (EPSRC). The aims of the workshop were to identify possible multi-disciplinary research teams which could begin to address the research issues pertinent to achieving a sustainable urban environment. One outcome of the workshop was the formation of the IDCOP consortium. Following the workshop the IDCOP core team conducted a series of face-to-face and virtual meetings with other SUE consortia and the EPSRC to refine the “initiating innovation change model” which had been developed by the whole IDCOP consortium at the workshop (Figure 1). Through these meeting the Figure 1: The initiating innovation change model 104 following factors emerged to shape the consortium’s vision: • People are at the core of sustainability. Thus, the focus of the work of the consortium should relate directly to the spaces which most people occupy during their typical day; • The vast majority of the urban environment has been constructed. Manipulating this built infrastructure to improve its impact on people in a sustainable way is singularly the most difficult and challenging issue facing built environment professional in the UK; • Processes, strategies and technological developments could be extended to new build. In essence, the research team identified the need to study people focused systems, derive models and theories that explain and describe the systems, and investigate how innovative technology could be used for new/improved products and processes which would reduce any adverse affects of buildings on the environment. In particular the research team aims to better understand the: • impact that the use of buildings have on the environment and quality of life of occupants/users; • changing demands being made of existing buildings (e.g. life style changes, climate change etc); • potential for technical/operational developments to improve the performance of the building; and • barriers to implementation (i.e. stakeholder reticence, the role of whole life thinking etc). Through a better understanding of the above the research team hope to provide the fundamental knowledge necessary to underpin demonstrable advances in improving the sustainability of existing buildings on the environment over the short to medium term. THE IDCOP CONSORTIUM RESEARCH FRAMEWORK In order to assist in the conversion of the consortiums broad aims to more focused objectives the team developed a theoretical framework to describe the innovation that is required if the existing built environment is to be made more sustainable (Figure 2). A More Sustainable Urban Environment Implementation Strategies Product Innovative Solutions to meet Opportunities for Change Baseline Knowledge Product / People Product People / Product / Process Product / People Product Process / People Process / People People Process Process Process Existing Urban Environment (Drivers for Change) Figure 2: Interaction between research themes and key drivers. 105 In an attempt to achieve a more sustainable urban environment it is first necessary to establish the baseline knowledge, for each of the key drivers, from which improvements can be made (Theme 1). Whilst this will ostensibly involve the study of Products, People and Processes it will also be necessary to examine how People relate to both Products and Processes. Once the baseline knowledge has been established innovative solutions need to be developed to meet the opportunities for improvement (Theme 2). However these solutions must not solely focus on the technological development of new Products and Processes but must also examine how People will relate to the Products and Processes. In this way People’s concerns/desires can be addressed during the development of the new Products and Processes. If the new Products and Processes are to have a positive impact on the sustainability of the urban environment then they will need to be widely adopted. Theme 3, which is ostensibly People focused, will examine alternative implementation strategies to ensure that the new Products and Processes that emerge from the project will indeed make a demonstrable improvement to the sustainability of the urban environment. THE IDCOP RESEARCH PROGRAMME Through a detailed consideration of the theoretical framework it became clear that to address all the issues pertinent to improving the sustainable performance of the UK’s existing building stock was beyond both the scope and resources of the consortium. As such a more narrow focus to the research project was sought. Through a series of discussions both within the IDCOP consortium and with other interested parties the role of the building façade as a mediator between internal and external environments was identified as key contributor to the sustainability of existing buildings. The façades of most existing buildings can be considered as passive systems. They act primarily as a climate moderator receiving the impacts of sun and wind whilst controlling the amount of air, sunlight, and sound passing through to the occupants. Consequently their performance directly impacts on the consumption of energy required to maintain a quality internal environment. So how well are existing UK building façades performing? If they are underperforming what can be done to the façade to improve their performance? How will changing demands affect their performance requirements? Could, a dynamic façade be developed which would optimise the energy exchanges to produce an environment conducive to maintaining a high level of well-being and consequently high productivity in the workplace whilst minimising energy consumption and pollution? What further research would be needed to achieve such an evolution? In addition to their direct impact on the internal building environment building façades also consume significant resources over their life time through routine maintenance and refurbishment. But, are our current approaches to maintenance and refurbishment sustainable? Is there inherent waste within maintenance planning systems? How should environmental and social issues be considered as part of building life cycle analysis? How will changing performance demands be reflected within life cycle modelling? Could an active façade provide performance data that could reduce the levels of waste associated with its maintenance and refurbishment and improve the reliability of life cycle performance models? What further research would be needed to achieve such change? I order to achieve a dynamic façade within existing buildings would require both the development of innovative products and processes to improve the buildings performance and, implementation strategies to ensure the acceptance of the products and processes amongst the stakeholder groups associated with the maintenance, refurbishment and use of the building (ClementsCroome et al, 2003). Further, developing these products, processes and strategies would demand a systemic, holistic approach which examined the interactions between the technologies and those who live and work within the building as well as the science and engineering required to develop the technologies. Thus in focussing on the building façade the research team identified the core objectives for the IDCOP consortium. These are to: ƒ explore the technical, economic, social and environmental implications for the development and use of building façades as ‘environmental mediators’; 106 ƒ ƒ develop new rules, standards and procedures for their design, production and maintenance; and establish implementation strategies to ensure the effective take up of the research outputs by industry and the wider research community. In addressing these objectives the research will take account of changing social attitudes and behaviour towards building use, of new national and global performance targets for energy and emissions control, and the results of predictive models of climate change. IDCOP WORK PROGRAMME Following the formulation of the research objectives the consortium members established an integrated work programme in which researchers from each of the academic partners worked together in multi-disciplinary teams. The work programme comprises three specific work packages. Work package 1 (Responsive building envelopes) seeks to develop and integrate various innovative façade components into existing building envelopes. The integration of solar gain control and natural lighting into a building façade should result in enhancement in the performance of the sustainable built environment and result in a major contribution to energy efficiency through a decrease in consumption, enhancement of thermal comfort and a reduction in CO2. The effectiveness of the solutions will be assessed in live building tests. Work package 1 is further broken down into the following sub packages • WP1.1: Potential of Smart Façades in the UK Built Environment: This sub package will encompass UK climate and building stock analysis and a comparison will be made with the building stock of Southampton University. • WP1.2: Fabrication and Evaluation of Holographic Optical Elements (Double Glazing Units): This sub package will seek to develop a miniature tracking HOE system which is autonomously powered and incorporated within a standard double glazed unit. • WP1.3: Development and Evaluation of Smart Glazing systems: This work package will combine simulation of performance of dynamic façade components in the building envelope with practical measurement and assessments obtained from real-time monitoring and control of a room fitted with electrochromic and HOE glazings elements. • WP1.4: Demonstration of SMART Façades: In this sub package the simulation work carried out previously will be extended through its associated practical projects. The prototype designs will be incorporated into a test-bed room and its performance evaluated for both thermal and illumination effects. Comparative analysis of computer modelling and the data acquired from other real installations will allow feedback to and from occupiers / managers, aid prototype refinement and model validation. Work Package 2 (Improving the sustainability of existing building envelopes) seeks to develop new processes, technologies and components for the operation, maintenance, repair and refurbishment of existing built assets that reduces their adverse impact on the environment (reduces waste and consumption of energy) whilst improving living and working conditions. Work package 2 is broken down into the following sub packages: • WP2.1: Sustainable Maintenance and Refurbishment of Buildings: This sub package seeks to develop a new approach, based around whole life thinking, to maintenance and refurbishment planning which will reduce the levels of waste associated with maintaining a building and provide the opportunity to programme environmental and social improvements as part of the maintenance/refurbishment cycle. The new approach will be based on the development of a Through Life Environmental Business Model (Clenets-Croome et al, 2003). The use of the model will result in more efficient and effective maintenance/refurbishment planning which will allow incremental improvements to be made to the sustainability of existing buildings. • WP2.2: Embedded Sensor Technology and Occupant Behaviour: This sub package seeks to investigate the extent to which embedded sensor technology, retrofitted to existing buildings, 107 can be used to covertly manage energy consumption and overtly provide information on the performance of buildings which stimulate changes in occupier behaviour to consume less energy. The use of these sensors will result in major contribution to energy efficiency through a decrease in consumption, enhancement of thermal comfort and a reduction in CO2. • WP2.3: Intelligent Buildings for Personalisation: This sub package seeks to develop personalised micro-environments which create a pleasant and up-lifting atmosphere. The relationships between the buildings and human beings can be seen as a semiotic process. The outcomes of tested techniques using intelligent agents will enhance negotiation and collaboration between all stakeholders in design of personalised buildings. Work Package 3 (An integrating vision for a sustainable built environment) seeks to integrate the work of IDCOP and provide the infra-structure for the exchange of ideas and development of cross cutting issues. The programme will also facilitate exchanges between members of the IDCOP consortium, other SUE Consortium and the International academic community. The package is broken down into the following sub packages. • WP3.1: Indicators for Mapping and Measuring Robustness, Resilience and Adaptiveness: The issues of developing a sustainable urban environment present a new interdisciplinary challenge. This sub package will develop a mechanism for integrating the consortium’s work across SUE IDCOP projects, developing and providing new metrics to support exchange of knowledge and exploration of emerging issues. • WP3.2: Extending Vision for a Sustainable Built Environment: This sub package will extend the mechanisms developed above to include other SUE consortia and International Research Groups. • WP3.3: Achieving a Sustainable Built Environment through the Maintenance and Refurbishment of Existing Buildings: This sub package will examine the fundamental issues that need to be addressed if routine maintenance and refurbishment is to act as a vehicle for improving the sustainability of the existing built environment (Jones et al, 2003, Jones et al, 2004). All the work packages are subject to annual review and modification may be made to reflect research findings and changing external conditions. EXPECTED OUTCOMES The aim of IDCOP is to study people focused systems, to derive models and theories that explain and describe the systems, and investigate how innovative technology can be used for new/improved products and processes which will reduce any adverse affects of the buildings on the environment and improve the quality of life for occupants in an economically viable manner (Figure 3). As a consequence of the study built environment stakeholders should have: • a greater understanding of the performance, in terms of sustainability of existing buildings and of the options for improvement; • a greater understanding of interactions between people and the buildings they manage and use; • access to a range of prototype technologies, developed specifically for retrofit to existing buildings that can reduce the consumption of non-renewable resources and provide a high quality indoor environment; • access to a range of prototype technologies to provide performance data for a more sustainable building maintenance and refurbishment model; • access to whole life building performance models and toolkits; and • access to explanatory models to evaluate the impact of new products and processes to improve the sustainability of existing buildings. 108 . Figure 3: IDCOP Project Rationale The ultimate success of the IDCOP consortium will be judged against the take up of these outputs by both Industry and the research community. SUMMARY The project outlined in this paper is one of 14 related projects being funded by the Engineering and Physical Science Research Council through its Sustainable Urban Environments programme to address the wide ranging issues related to achieving a sustainable urban environment. The focus of this project is on the micro (building) level where the researchers believe a better understanding of the fundamental relationships between buildings, people and the environment is required if real improvements in the ‘sustainable’ performance of the urban environment are to be achieved. It is hoped that the fundamental knowledge resulting from this project will be taken up by the various built environment stakeholder groups and that demonstrable improvements to the existing built environment will be seen in the short to medium term. REFERENCES Clements-Croome D, Jones K, et al, ‘Responsive Building Envelopes for the Urban Environment’, Proceedings of CISBAT 2003, Innovation in building envelopes and environmental systems, October 2003, www.buildingenvelopes.org. Clement-Croome, D, Godfaurd, J, Loy, H & Jones, K, ‘Through-life environmental business modelling for sustainable architecture’, CIBSE/ASHRAE Int. conference on building sustainability value and profit, 24-26 Sept., Edinburgh, ASHREA 2003. DETR, (1999) “A better quality of life – a strategy for sustainable development in the UK”, DETR, London, ISBN 0-10-143452-9. DETR, (2000) “Building a better quality of life – a strategy for sustainable construction”, DETR, London. Rethinking Construction Ltd, (2003) “Demonstrations of Sustainability”, Rethinking Construction Ltd, London. DTI, (2001) “Constructing the future”, The Built Environment and Transportation Foresight Panel, www.foresight.gov.uk, London. Jones, K, Clements-Croome, D, Bahaj, B & Gann, D ‘Improving the Sustainability of Existing Buildings’, Second International Conference on Construction in the 21st Century (CITC-II) Sustainability and Innovation in Management and Technology, 10-12 December, 2003, Hong Kong. Jones, K, & Clements-Croome, D ‘Towards a sustainable urban environment’, COBRA 2004, http://www.rics-foundation.org/publish/index.html. 109 The Brundtland Report (1987) Our Common Future. Oxford University Press, ISBN 019282080. UN Department for Economic and Social Affairs (1992) Agenda 21, http://www.un.org/ UN Framework Convention on Climate Change (1997) The Kyoto Protocol, http://www.unfccc.int/ UN World Summit on Sustainable Development (2002) What was achieved and the way forward, http://www.un.org/. 110