The construction industry, along with its support industries, is one of the largest exploiters of natural resources, both renewable and non-renewable (Dixit et al. 2010). The built environment is an energy and resource sink with an immense impact on the natural ecosystem. Buildings consume about one-third of the world’s energy (Srinivasan et al. 2012) and generate between 40 -50% of global greenhouse gases (Asif et al. 2007). Furthermore, building construction consumes roughly 40% of the planet’s raw materials, which is around three billion tons annually (USGBC; Edwards 2005). Globally, building construction depletes 40% of raw stone, gravel, and sand, 25% of virgin wood, and consumes 16% of water annually (Horvath 2004; Dixit et al. 2010).
Buildings are responsible for a significantly large share of consumed energy. According the US Department of Energy, commercial and residential buildings together, utilize approximately 40% of the total energy consumed in the US (DOE Energy Databook, 2003). Energy consumption is a significant problem facing the world as it enters the 21st century. Energy consumption throughout the world has increased dramatically over the past century with further increases estimated for the future (Das 2005). Population growth increases the need for more residential housing, putting further stress on energy.
Growing populations require a growing built environment with increasing energy and resource demands. The magnitude of the built environment coupled with environmental constraints such as the energy crisis, global warming, the growing concern over wastes and emissions, and the depletion of fossil fuels and natural resources underline the need to find less intensive, more sustainable building strategies. It is imperative to reduce the environmental impacts of our built environment and become more responsible stewards of the earth and available resources for the sake of our species survival.
The interdependence of natural ecosystems and the built environment point to the far-reaching effects of building design and material decisions on the environment (Edwards 2005). With large scale depletion of natural resources, deforestation and considerable destabilization of the environment, the need to co-exist with nature in order to preserve our surroundings is rapidly gaining importance. The manner in which we design and construct our built environment is a significant part of being more responsible stewards of the planet; a concept labeled “sustainable construction.” Sustainable construction encompasses the techniques of construction and building material choice, while also considering matters of design, development and urban planning (Moore 2008). To achieve the goals of sustainability in construction, it is necessary to adopt an integrated multidisciplinary approach covering features such as: improved use of materials, reuse and recycling, energy saving and emissions control (Asif et al. 2005).
Globally, there is a critical need for environmentally sustainable mass-produced housing. One of the critical factors in the transition to global sustainability is the development of mass-produced environmentally-benign housing is (Coulson & Fuller 2009). Present construction trends have been found to be unsustainable from resource and environmental perspectives when conventional materials— steel, timber, cement, sand, clay and gravel aggregates— are used (Chopra 1991; Tiwari & Parikh 2000). Current mass housing in industrialized countries like the United States, Europe and Australia are constructed almost exclusively from these common building materials, which are, with the exception of timber, energy-intensive to produce and non-renewable (Walker-Morison et al. 2007). These houses have high embodied energy contents and associated Global Warming potentials (GWP) (Newton 2001). Additionally, the mixed nature of building materials makes recycling of demolished buildings difficult and often financially unprofitable (Edwards 2005; Barkkume 2008).
The materials from which a building is constructed makes a significant contribution to the building’s overall environmental impacts (Harris 1999). The materials which come from nature are normally found in an impure form, as in ores. Extraction and purification of materials from their natural ores is an involved activity which consumes energy and water while also resulting is waste and emissions generation (Asif et al. 2005). For example, at a local level, the extraction of raw materials produces noise, air and water pollution. At a global level the carbon dioxide (CO2) produced by using energy to manufacture and transport materials is rapidly accumulating and contributing to the greenhouse effect (DOE). Further, there are associated environmental consequences with waste disposal after construction and demolition. In the US alone, construction and demolition waste account for 136 tons per year of solid waste, which is approximately 2.8 tons per person per day (Edwards 2005).
A new paradigm in mass-produced housing design, material usage and rapid construction is urgently required if the needs of growing populations are to be met in an affordable and environmentally sustainable way (Coulson & Fuller 2009). Current housing construction practices are unsustainable in terms of materials, energy and resource use. The focus of this research is to evaluate the environmental impacts of common building materials used in housing and to explore to what extent renewable or eco-alternative materials are currently available for the transition to a more sustainable building paradigm.