Sustainable housing and outcomes of the Cairnlea Ecohome
Creators: name: Rahman, Syed Mohammad
Publisher: name: RMIT University
Year: 2024

description: The effect of global warming is a growing concern for the global community. This concern is reflected in politics, business, corporate charters, local government charters, electronic and print media and so on. The core to this issue is green house gas (GHG) emissions due to anthropogenic activities. In a developed country such as Australia, residential green house gas emissions are responsible for about 20% of its total GHG emissions. Therefore, sustainability in the housing sector is important towards overall reduction of GHG emissions.<br><br>Australia's progress in sustainable housing is discussed. There are legislation and financial incentives towards sustainable housing. All the states and territories and the Commonwealth provide financial incentives for PV energy, rain water tank, solar hot water systems to supplement high initial set up cost. A number of high quality rating tools are developed in Australia to facilitate and administer energy efficient design for residential and commercial buildings. There are many good examples of sustainable housing throughout Australia.<br><br>The Ecohome at Cairnlea, Melbourne is a demonstration home as well as part of this research project. This standard home added with 'off the shelf' sustainable features and having a FirstRate star rating of 6 stars is intended for the volume home market. This thesis presents sustainability outcomes of the Ecohome.<br><br>Thermal performance of the Ecohome is presented qualitatively and quantitatively. Monitoring data from 14 months' show that approximately two-thirds of the time, indoor temperatures remained in comfort zone (18-26 C) without artificial heating or cooling. Monitoring of indoor air quality included carbon dioxide, humidity and carbon monoxide. Monitoring data from sealed house and while the residents were living in are presented. Humidity level was within 35-45% most of the time while carbon dioxide was under recommended level (1080ppm) in the lower floor (living area and kitchen). Carbon monoxide level within the house was negligible. Significant energy and water savings were realised in the Ecohome. On per capita basis, 45% savings in water usage, 30% savings in electricity usage while similar gas usage was observed compared to average Melbourne home. Residents' feedback on sustainable features was mostly positive (except sisal carpet).<br><br>Several thermal performance indicators are proposed and presented. These include 'Attenuation Factor', 'Time Lag', 'Heating and Cooling Need' in degree hours, 'Degree C Warmer' and 'Percentage Time in Comfort Zone'. Some of these concepts were used by some authors with different nomenclature; therefore, an attempt was made to unify them. Monitoring data was utilized to measure thermal performance of the Ecohome using these indicators.<br><br>Prediction of indoor temperature when outside temperature is known is of much interest. Statistical and empirical methods were employed for this purpose. Both statistical method and Givoni method produce reasonably good prediction with deviations from actual observations being in the range of 2 to 3 deg C.<br><br>This research provides valuable monitoring results in this emerging field. Proposed thermal performance indicators are a significant contribution to the body of knowledge.<br>