CHAPTER 3 RESEARCH METHODOLOGY
CHAPTER 3 RESEARCH METHODOLOGY
Building Information Model can be applied in various stages from feasibility study to demolition stage. The application of BIM in energy performance and life cycle cost assessment are presented in this research. According to Grilo and Jardim-Goncalves (2010), Building Information Modelling can be applied to the design of energy performance of a building and to evaluate the difference between various construction materials of the envelope. BIM becomes possible to assess the performance of the life cycle cost of the building in the early design stages.
To study the benefits and ambiguous of the integration of the BIM and Life Cycle Cost Assessment, the energy-saving performance of the curtain wall system was focused to have assessment in annual energy consumption , by using BIM softwares. Through the assessment of energy consumption, the Life Cycle Cost of HVAC system and lighting system of the commercial building can be evaluated.
To fulfill the aims of the research, an all-round research on the integration of BIM and life cycle cost assessment containing literature review, pilot study with its results, discussion, conclusions and recommendation. The research framework is illustrated as figure 3.2.1.
Figure.3.2.1 Research Framework
The purpose of the literature review is to study about the BIM application in the construction industry in recent years. Besides, reading other literatures before pilot study can comprehend the knowledge about the definition of BIM, formulas of life cycle cost and the process to assess the energy saving performance of curtain wall via the BIM environment. Besides, the definition, merits and elements of life cycle cost have been studied in the review. Some relevant books, journals and papers are the major sources of literature review in this paper.
Data Collection and Practicability of Pilot Study
In this stage, a commercial building with curtain wall system is selected to have pilot study in this paper. Architectural 2D drawings of the building and some detail information about the building should also be collected at this stage. Furthermore, various data about curtain wall should be amassed, such as the shading coefficient and the lighting transmittance of certain curtain wall systems of the commercial building. After the preparatory study of the data and drawings, the practicability of conducting the pilot study can be assessed. The examination of BIM softwares which can be adopted in this study should also be conducted at this stage.
Development of Building Model
With the collected 2D drawings of the commercial building, the floor plans of the buildings are converted to a 3D model drawing by entering those dimensions to eQUEST. After that other information about curtain wall system, such as the type and specification of curtain wall system, should be inputted to the software.
Conducting Pilot Study
Background of the Pilot Study
In Hong Kong, around 66% of electricity consumption was used by the commercial sector. In order to investigate the energy saving measure of the commercial sector, a commercial building with a curtain wall system which is one of the current methods to save electricity is the targeted building in this study. The design and layout out of the building assessed is similar to the commercial building nowadays. Besides, ten types of curtain wall are selected to be assessed with the target building and the cost data of those curtain wall systems are collected from consultant firms and contractors. In this pilot study, there are three sustainable performance assessments. With the integration of BIM and the pilot study, the annual energy consumption of the commercial building can be assessed with the use of BIM. After the assessment of performance, the life cycle cost which is used to assess the cost of an asset over a specified period of time can be calculated.
Information of the Proposed Building
Usage of Building
Location of Building
Hong Kong Island
Number of Stories
27 stories with a basement
Curtain Wall System
Software Adopted for 3D Building Model Drawing Development
Software Adopted for Sustainable Performance Assessment:
Software Adopted for Life Cycle Cost Assessment:
Microsoft Excel 2013
Table 3.6.1 Background Information about Pilot Study
eQUEST is used to assess the energy performance of the targeted building. Three assessments are included in energy assessment and they are i) relationship between U-value and energy consumption of HVAC system, ii) relationship between shading coefficient and HVAC system and iii) visible transmittance and lighting system. After the energy performance assessment, an economic performance assessment would be conducted. The value of energy consumption obtained by eQUEST in chapter 6 will also be used to calculate the life cycle cost of the building with the use of Microsoft Excel 2013. About the detail processes of calculating life cycle cost, they will be discussed in Chapter 7.
Softwares Adopted in Pilot Study
eQUEST is a 6D BIM softwares that provides whole building energy performance assessment. It is widely used and popular in United States and Canada because of its high accuracy. With its wizards and dynamic defaults, eQUEST can rapidly conduct whole-building performance simulation analysis and generate various energy consumption reports, such as Annual Energy Consumption by Enduse report. Besides, eQUEST is able to assess the performance of building throughout the entire design process, from the conceptual stage to the final stage of design. About the simulation engine of eQUEST, DOE 2.2 is also popular within various BIM softwares because of its widely used. Last but not least, eQUEST has been tested according to ASHRAE Standard 140 which is a well-known international standard.
Microsoft Excel 2013
Microsoft Excel is a spreadsheet software developed by Microsoft. It has been widely used in different industry because of its fantastic application in calculation and graphing tools. Apart from the special features of forming two-dimensional and a very limited three-dimensional graph, Microsoft Excel still has the basic features of spreadsheet, such as using the numbered rows and the numbered columns to define the location of the cells.
Declaration for Software Adoption
It is declared that this paper has no relationship or connection with the developer of software mentioned above, namely, eQUEST and Microsoft. Those softwares have been used because of three reasons. First of all, they are capable to perform the assessment, such as energy consumption assessment, required in this study. Secondly, they are well-known softwares in the construction industry for assessing building performance in energy usage and life cycle cost calculation. Finally, those softwares have developed education or free visions in which students or the public can download from its official website.
After the sustainable performance assessment via BIM environment, the discussion about the integration of BIM and sustainable assessment will be conducted. The benefits and ambiguous encountered by 6D BIM can be identified in the process of assessment, especially for eQUEST. Furthermore, the results of curtain wall systems in energy and economic aspect will be consolidated and form an overall performance assessment. The most economic, environmental and optimum types of curtain wall system can be selected by different graphs.
Conclusion and Recommendation
After the stage mentioned above, the findings about the features of the curtain wall system and energy consumption can be consolidated at this stage. Also, limitations that restrict the accuracy of the study would be pointed out in chapter 9. Besides, some recommendations for further study about the improvement of the integration between BIM and sustainable assessment of the building would be made.