ABSTRACT

The rapidly emerging movement seeking to move the construction of the built environment into a sustainability framework must create adequate decision making systems that allow the selection of the optimum solution from among a wide range of alternatives. Chief among the difficulties with developing these systems is that the issues involved have no common denominator that allows the determination of the relative worth of resources such as energy, water, materials, and land alongside environmental protection and the preservation of biodiversity and environmental amenity, to name a few. In the case of materials selection the trend has been to determine the relative ranking of alternatives based on environmental effects such as embodied energy and greenhouse gas generation. However the ultimate procurement of materials will ultimately rely on cost and performance as the main criteria for selection. Decision systems that use other than these criteria will probably be of little use. Although fraught with difficulties, the solution presented here is ultimately the sole useful approach to developing adequate decision systems for sustainable construction. The solution is the internalization of environmental costs or externalities, sometimes referred to as ‘social costs’.