Identification of key factors that aid the decision on whether to refurbish-reuse or demolish-rebuild existing and newly designed buildings and highways

The demand for construction and demolition (C&D) of existing and new buildings have been increasing every year, as a result of this, a significant increase in waste has been witnessed. According to Defra, the UK is producing on average of 110 million tonnes of C&D waste every year since 2010. This indicates that a well informed decision is required for any building or site that is being considered for C&D works in order to reduce waste. The aim of this research project is to identify the key factors that play a vital role in deciding whether to refurbish or rebuild any existing building and highway pavement that is reaching its design life and also newly designed buildings for future decision-making. The objectives are; to develop different sets of frameworks to identify the key factors and to achieve a well-informed decision criteria based on the identified key factors. The methodology used to complete this research project, consists of two parts; investigation of different aspects of waste management and similar cases of some previously refurbished or reconstructed buildings, collection of waste statistics from different construction sites with the intention to develop different sets of framework for the identification of decision-making factors and secondly, the use of Revit (BIM) CAD software and Tally (LCA) tool for application of these factors, where these were applied to some of the existing or old and new buildings in order to check their reliability. The reported research project has identified 11 key factors and their application on the existing/old and newly build structures. It has been observed that an enormous amount of waste can be prevented in the future at an early stage of project planning through making a proper and well informed decision about any existing building or a new development with the scope of future possibilities of amendments to it when nearing the end of design life. Following the application, an expert opinion survey was conducted for validation of the key factors, then these factors were arranged in a priority order by deciding a threshold for each of the factors. Pavement conditions are analysed and a decision on whether to refurbish or recycle is identified accordingly. Following the application and validation of factors onto different buildings and highway pavements, it has been observed that the decision of whether to refurbish or rebuild vary in every case, given the scenario that how much design life is left and what is the current state of the building and most importantly, what would be the cost and environmental impact in each case. However, in some cases, it has been clearly observed that the decision to refurbish is more suitable than to rebuild due to design life being left is significantly higher and the proposed purpose of the building use complies with the current layout.