Ngo, T; Crawford, R; Gammampila, R; Lu Aye & Mendis, P 2009, 'Embodied energy analysis of prefabricated reusable building modules for a multi-residential building', Solar09, Proceedings of the 47th ANZSES Annual Conference, 29 September-2 October 2009, Townsville, pp. 1-10.
Abstract
The construction and operation of buildings is responsible for significant environmental impacts, predominately through resource consumption, waste production and greenhouse gas emissions. It is important to consider the life cycle impacts of buildings, as the environmental impacts of initial construction can be just as significant as those associated with their operation. A range of different strategies have been employed in an attempt to reduce these impacts, such as the use of less resource-intensive materials, materials with recycled content and the reuse of materials. Also, a number of researchers have highlighted the potential benefits in preventing or reducing construction waste. Prefabrication is one strategy considered to provide improved environmental performance for construction. However, there is an absence of detailed scientific research or case studies dealing with the potential environmental benefits of prefabrication, particularly the embodied energy savings resulting from waste reduction and the improved efficiency of material usage. This paper aims to quantify the embodied energy of a modular prefabricated steel multi-residential building in order to determine whether this form of construction provides improved environmental performance over conventional concrete construction methods. Furthermore this paper assesses the potential benefits of recyclability of materials, reducing the space required for landfill and need for additional resource requirements.
An eight-storey high, 3943 m2 multi-residential building was investigated. It was found that the steel-structured prefabricated system resulted in reduced material consumption by up to 78% by weight compared to conventional concrete construction. However, the prefabricated steel building resulted in a significant increase in embodied energy compared to the concrete building. It was shown that for both the concrete and prefabricated steel options, the reinforced concrete floor panels represent the largest proportion of the total embodied energy. It was also shown that there was significant potential for the reuse of materials in the prefabricated steel building, representing up to an 82% saving in embodied energy and 51% materials saving by weight. This form of construction has the potential to contribute significantly towards improved environmental sustainability in the construction industry.
Keywords: Embodied energy; prefabricated building; waste reduction.