Minimising the impact of resource consumption in the design and construction of buildings Stephen Pullen1, Keri Chiveralls1, George Zillante2, Jasmine Palmer3, Lou Wilson4 and Jian Zuo1 1School of Natural and Built Environments, Barbara Hardy Institute, University of South Australia, Adelaide, Australia 2School of Architecture, Landscape Architecture and Urban Design, University of Adelaide, Australia 3School of Art, Architecture and Design, Barbara Hardy Institute, University of South Australia, Adelaide, Australia 4 School of Natural and Built Environments, Hawke Institute, University of South Australia, Adelaide, Australia ABSTRACT: This paper reports on the preliminary stages of a project entitled Re-considering sustainable building and design: a cultural change approach. In particular, it focusses on that part of the project which deals with minimisation of the impact of resource consumption in the design and construction of buildings. Previous research on the various aspects of resource use in construction is reviewed. The interrelated factors which are relevant to the project are described including the usage of raw materials, consumption of energy and water to manufacture building elements, greenhouse gas emissions and landfill disposal. Some case studies are examined which indicate possible means to improve performance in this area and a hierarchy of actions for the recycling of construction materials required is presented. This forms a framework to guide the research project in its aim of developing a clear pathway to minimise resource usage and waste reduction. It is likely that the comprehensive adoption of procedures and strategies to minimise the impact of resource construction will necessitate a change in the attitudes and culture of all stakeholders involved in the construction of buildings. Conference theme: Architecture and the environment Keywords: Construction materials, resources, environmental impact INTRODUCTION The purpose of this paper is to describe the preliminary stages of research being carried out at the University of South Australia within the three year project entitled Re-considering sustainable building and design: a cultural change approach supported by an ARC Linkage grant. The aim of the project is to develop a clear route to take building procurement teams (i.e. the client, architects, designers, planners, engineers, building contractors and facility managers) from current levels of knowledge and practice in the minimisation of resource usage and waste reduction towards international best practice and total waste elimination. The project has three themes which are: the cultural shift required to move the industry towards zero waste, the practical and technical aspects of environmental sustainability and the effects of regulation. This paper focusses on the practical and technical aspects of environmental sustainability, particularly as they relate to resource efficiency and waste elimination, and draws together various aspects of minimising resource consumption. Initially, the adverse environmental effects of constructing buildings are considered with particular reference to resource usage by reviewing previous research in this area. Some case studies are also described which feature buildings and infrastructure with a lower environmental impact and which provide pointers in the development of a comprehensive guide to minimise the use of resources. Reference is made to a hierarchy of principles for minimising resource consumption in the design and operation of buildings and this provides a framework to guide subsequent research and contribute to the overall aims of the project. 1. BACKGROUND Although the construction of buildings normally provides undeniable benefits to the community, there are hidden costs to be paid in terms of the potentially harmful effects on the physical environment and natural ecosystems. The processes of erecting, renovating, maintaining and demolishing buildings have various impacts and in recent decades there have been efforts made to minimise these effects. The manufacture and production of building materials and components uses raw material resources, consumes energy, produces greenhouse gas emissions and can consume significant quantities of water. At the end of a building’s life cycle, a substantial proportion of the demolished materials may add to the environmental burden as landfill. Concern over the environmental effects of resource consumption has not been confined to the construction industry. In 1997, Von Weizsacker at the Wuppertal Institute published the Factor 4 book which advocated a 75% increase in the efficiency of using all resources to minimise their usage and significantly reduce greenhouse gas emissions and water consumption. The concept of drastically reducing consumption for any given purpose or product was the central focus and more recently, 80% efficiency increases are being targeted in Factor 5 (Von Weizsacker et al, 2009). The concept of decoupling resource consumption from growth by focusing on the services that are provided rather than the product that supplies them has been explored by various researchers (UNEP, 2002; Ness and Pullen, 2006). The ratio of material input per service (MIPS) has been developed by Schmidt-Bleek (1993) and promoted as a concept to measure the usage of materials needed to provide services in the community. In the case of buildings, and at its most basic, MIPS would equate to the quantity of materials used to provide shelter, function and comfort. The methods for calculating MIPS can be complex and are described by Ritthoff et al (2002). In general, those services which can be provided with lower material inputs will have less effect on resources, energy and water consumption and a reduced impact on the natural environment. Life cycle analysis of materials and products provides a further method of assessing environmental effects and this has the advantage of including end-of life and re-use/disposal scenarios as well as biodiversity impacts. Of the various sectors of national economic activity such as mining, manufacturing and transport, construction constitutes a significant proportion and is, therefore, responsible for a sizable share of overall environmental impact. The following section describes these impacts with particular reference to construction materials. 2. CONSTRUCTION MATERIALS 2.1 Material resources Traditionally, construction materials have been supplied from raw material resources that are in relatively plentiful supply and are unlikely to be exhausted in the short term (DEH, 2006). However, the mining and quarrying of raw materials can have environmental impacts such as land and riparian disturbance as well as pollution effects (Carpenter, 2011). Furthermore, there are particular materials that require special consideration. For example, the exploitation of non-sustainably harvested timber, particularly in tropical regions, may threaten the viability of local flora and fauna and render landscapes susceptible to instability. More modern construction materials such as steel, aluminium and polymeric materials involve substantial extraction and manufacturing processes with associated environmental effects. Building materials account for approximately half of all materials used and a similar proportion of all of the waste generated globally (Edge Environment, 2011). The avoidance of manufacturing and supplying new construction materials can be assisted by maximising the re-use and recycling of demolition materials. In fact, the urban environment represents a vast store of resources that has been inherited from previous generations and which may be used so as to avoid some of the environmental disadvantages of new construction developments. In a very broad sense, the World Bank (2001) commented on these resources as an inheritance from previous generations. Expressed simply, previous communities have paid the price for erecting built assets in terms of cost, time, resources and energy, and subsequent generations can benefit from this. In fact, the utilisation of such assets in the form of re-using construction components or the recycling of demolition materials from older buildings and structures has occurred ever since building began. There are many examples including the re-use of masonry from the constructions of previous pharaohs in ancient Egypt (Sullivan, 2008), the sourcing of materials from the Great Wall of China (National Geographic, 2011) and the use of stone from Hadrian’s Wall in the UK by local dignitaries after the departure of the Romans (ICONS, 2006). Although the dismantling of ancient structures would not be considered appropriate in modern times, the principle of re-using materials from less notable buildings has definite environmental advantages by avoiding the further exploitation of natural resources. 2.2 Energy consumption and associated emissions The manufacture and supply of construction materials consumes large amounts of fossil fuel based energy, produces significant quantities of greenhouse gases and contributes to climate change. The quantification of energy consumed by buildings has normally been referred to as operational energy i.e. the energy used for heating, cooling, lighting, appliances and services. However, this does not consider the energy consumed in the manufacture and transport of building materials which is known as embodied energy. Embodied energy can amount to a substantial proportion of the life cycle energy usage of buildings when both the