A framework for appraising construction projects using carbon footprint

The construction industry contributes over 50% of the United Kingdom’s total CO2 emissions. Given the need to reduce CO2 emissions, the role of the construction industry in this endeavour cannot be overemphasised. The construction industry has traditionally addressed similar matters of optimising performance using project appraisal techniques. The appraisal techniques provide a good basis for decision making but have mostly concentrated on financial performance. Although some appraisal techniques that address non-financial performance have been devised, none to date directly address the crucial issue of CO2 emissions. This paper presents work undertaken to develop a framework for appraising construction projects using the carbon footprint of the construction project, and other, processes over the life cycle of a reinforced concrete building project. The framework is based on process and energy analysis and aggregates CO2 outputs from materials manufacture through to project disposal at the end of the project life. The framework was developed to facilitate decision makers to estimate the quantity of CO2 emissions and the impact different alternatives have on this quantity. It is argued that the proposed framework will facilitate decision makers to appraise construction projects on the basis of carbon footprint.