Masters Research - Master of Architecture (M Arch) / This thesis aims to quantitatively evaluate the impact of design decisions on the life cycle energy use and the resultant carbon dioxide equivalent gas (CO2-e) emissions of a house. It will compare the modelled life cycle impacts of three architects’ house designs in a temperate zone. It will suggest that the impact of a dwelling’s life and death is dependent on the decisions of the designer at its conception. Research into energy use in buildings previously has focused on two aspects: the embodied energy in materials used in construction and in the energy used to heat and cool a building. This dichotomy is also evident in studies of CO2-e impact where the argument previously focused on the relative importance of embodied impact versus operation impact. The debate was further obscured by a lack of differentiation between energy use and CO2-e impact as issues. It is proposed that a designer’s decisions will affect the energy used and CO2-e impact in the entire life of a building, both embodied and in operation. A life cycle analysis approach is developed from the perspective of a designer in a structured way, to form a hybrid framework for a holistic accounting process to assist design decision-making. Computer modelling programs are used and the results evaluated in the context of a modelled lifestyle. The BHP Steel LISA program, which assesses the impact of the materials used, is linked to NatHERS, a program used to rate energy requirement. In addition new spreadsheet based programs have been developed to model the site construction component of the life cycle, and the renovation component of a lifecycle. Also a spreadsheet program has been developed to convert the energy requirement output values from NatHERS to the number of hours a design is outside a defined temperature range. This allows an appliance to be modelled. The mental framework and method presented allows detailed analysis of design decisions. This method reduces the inherent complexity created in the design process when a designer desires to minimise energy use and CO2-e impact of a dwelling in a temperate climate. The method quantifies the difference in energy use and impact between specific design decisions in a life cycle. The quantified difference between specific design decisions is introduced as a concept and called the ‘D-value’. The difference (the D-value) between design options for specific combination of materials showed that design decisions may have significant impact over a life cycle. Energy use and CO2-e impact, though related, are shown to be two separate issues requiring a ‘both/and’ design approach.
| Identifer | oai:union.ndltd.org:ADTP/222146 |
| Date | January 2006 |
| Creators | Henriksen, Janet Elizabeth |
| Source Sets | Australiasian Digital Theses Program |
| Language | English |
| Detected Language | English |
| Rights | Copyright 2006 Janet Elizabeth Henriksen |
Page generated in 0.0022 seconds