BUILDING PERFORMANCE ASSESSMENT OF AN ECO-HOUSE IN MALAYSIA: A COMPARATIVE ANALYSIS Maisarah Ali Ph. D 1 Yousif A. Abakr Ph. D 2 Najib Ibrahim Ph. D 1 1 Department of Building Technology, Faculty of Architecture & Environmental Design, International Islamic University Malaysia, Kuala Lumpur, Malaysia 2 Department of Mechanical Engineering, Faculty of Engineering, International Islamic University Malaysia Keywords: Eco-house, Assessment Tools, Green Performance, Environmental Impact, Energy Efficiency, GBtool, BREEAM. Summary The paper presents a comparative study of an environmental performance assessment of an ECO-HOUSE in Malaysia using two established environmental assessment tools. The assessment of the ECO-HOUSE is undertaken taking into account off all ecological and bioclimatic features proposed by the architect such as shading systems, use of vegetation and stack effect in building design. A comparison is made not only between the assessment criteria of two tools i.e. BREEAM and GBTool, but also between the proposed design and a generic or typical design. A discussion is made of the relative ease and difficulty in implementing the two tools throughout the architectural design process and the need to balance between rigour, comprehensiveness, simplicity and ease in comprehending the output of the assessment tool. The potential and limitations of the two tools are discussed – while the framework of a new tool developed by a Malaysian architect for assessing the environmental impact of building design in its context is forwarded and the experience of integrating the use of the tools throughout the design process is highlighted. The comparative study hopes to contribute to the development of a tool that is comprehensive yet taking into account the characteristic of the tropical climate and the Malaysian context. 1. Introduction To make decisions, building designers need to predict and assess the performance of their ideas with respect to various criteria, such as comfort, aesthetics, energy, environmental impact, economics, etc. Performance prediction with respect to environmental impact typically requires complicated models and massive computations, which are usually possible only through computer-based simulation tools. Performance prediction process contains analyses of green performance indicators and descriptions of available tools, along with discussions on their use by different types of users and at different environmental and biophysical conditions. During the last ten years considerable research has been focused on the development of systems to assess the environmental performance of buildings. Several of these systems have gone the next step, to result in a labeling system that indicates clearly the building's approximate performance to end users. It is best to say "approximate", since building performance includes many factors, only some of which are measurable in an exact sense. The BREEAM system for example, provides performance labels suitable for marketing purposes, and has captured around 15% to 20% of the new office building market in the U.K. BREEAM The 2005 World Sustainable Building Conference, Tokyo, 27-29 September 2005 (SB05Tokyo) - 4665 - 20-007