THE UNIVERSITY OF QUEENSLAND Bachelor of Engineering Thesis Industry Workflow for Converting Building Information Modelling to Building Energy Modelling Student Name: Gareth Clark Course Code: MECH4500 Supervisor: Associate Professor Saiied Aminossadati Submission date: 25 October 2018 UQ Engineering Faculty of Engineering, Architecture and Information Technology [This page has been deliberately left blank] Executive Summary The building services industry is currently undergoing change as a rapid increase in sustainability awareness is being focused on around the world, bringing about a focus on energy modelling to analyze and predict building performance. To perform energy analyses, models are re-created due to software limitations where an already existing Revit model already exists. The aim of this thesis was to develop an effective technique for complex building energy modelling by converting a Building Information Model (BIM) into a Building Energy Model (BEM). This is done to create a workflow document for the conversion process. A secondary objective was a comparison between Revit’s building information-energy modelling (BI-EM), OpenStudio’s building energy modelling (BEM) and the converted BIM to BEM modelling (BIM-BEM) to validate the BI-EM and BIM-BEM models against the trusted BEM modelling. The project was completed through several primary steps in order to reach each objective. This approach was to first test processes for converting from Revit to OpenStudio, then create a Revit BIM model, prepare the Revit BIM model for conversion, convert the prepared Revit model to OpenStudio and run the simulation. This provided the necessary information to create a workflow document. The last step was to compare BI-EM, BEM and BIM-BEM as energy simulation methods. Findings showed that a clear workflow is able to be created with the primary method using gbXML geometry export from Revit into SketchUp (With an OpenStudio Plugin). The method for conversion was identified to require 6 main steps for the workflow from the start of receiving the Revit model through to running the OpenStudio simulation, this method is outlined below: 1) Pre-work in the Revit file, focusing on schedules and level properties; 2) Building geometry set-up, concentrating on the building envelope; 3) Space creation in Revit, detailing spaces and their associated properties; 4) HVAC zone creation in Revit, assigning the relevant zones to each space in the model; 5) Exporting as a gbXML, with a focus on model review and the settings for export; and 6) The set-up of the energy model, focusing on error checking and simulation parameters. This method requires a majority of the time spent preparing the Revit file for export by making specific adjustments to ensure the conversion works effectively. As with all newly developed methods, many limitations still exist within the process. A major limitation is due to the process heavily relying on manual adjustments which leads to the process becoming complex and tedious if the model not set up correctly from the start. This limits the ability to perform the conversion effectively if the building is too large or complex. The comparison between the three energy models showed the BIM-BEM results provided similar overall building results and similar design heating and cooling loads to BEM, with most zones producing design loads with less than 10%-15% difference between BIM-BEM and BEM with certain zones outlying the results causing the average difference between models to be 19%. Whereas the Revit model was highly dissimilar to BEM, with most zones design loads with over a 100% difference between BIM and BEM showing an average difference of 110%. ii | P a g e Acknowledgements Along the road of completing this thesis, I have been fortunate to be assisted by so many people that have had a large influence on the progress and execution of the project. I am extremely grateful to have been able to produce this project with my university supervisor Associate Professor Saiied Aminossadati, who was always willing to meet and guide me through the thesis process. A big thank you to FLOTH Sustainable Building Consultants for the opportunity to produce the Thesis and to everyone at the company who lent a hand in the project. Notably the BIM staff at the office, Andrew Reynolds (Previous National BIM Manager), Reegan Petty (Revit Modeller), and Matthew Boynton (Group BIM Manager), who continuously went out of their way to help where possible and sitting through the frequent questions I had about Revit. A special thanks to Tom Beckerling (ESD Engineer/Energy Modeller) for his constant guidance, advice and phenomenal support throughout the course of the Thesis and this past year. This project would not be the same without him and his continual input. I am immensely grateful to have had Tom as a supervisor, teacher, and mentor. Thank you to Makoto Dawson, David Yassa, and Matthew Newland for the support over the past three years through the joint struggle of university and for the thesis writing sessions together. Rhianna Cardamone and Joseph Lovie-Toon, thank you for your generosity, hospitality, kindness, and for your all round incredible personalities to make these university years far more enjoyable, never failing to liven the mood. Lastly, thank you to my parents for everything they have done and especially my incredible brother, Steven, for always being there as a pillar for support, friendship and advice, never failing to be there when needed. iii | P a g e Table of Contents 1.0 Introduction ..................................................................................................................... 1 1.1. Project Context ............................................................................................................ 1 1.2. Aims & Objectives ....................................................................................................... 2 1.3. Importance of Effective BIM to BEM ......................................................................... 2 1.4. Project Scope ............................................................................................................... 3 2.0 The Current Building Industry ........................................................................................ 4 2.1. Building Services Engineering .................................................................................... 4 2.1.1. Technological Advancements in Construction Sector .......................................... 4 2.1.2. Collaborative Engineering in the Building Sector ................................................ 5 2.2. Building Information Modelling .................................................................................. 5 2.2.1. What is Building Information Modelling? ........................................................... 5 2.2.2. Visual Introduction to BIM and its Features ........................................................ 6 2.3. Need for Sustainable Engineering ............................................................................... 7 2.4. Building Energy Modelling ......................................................................................... 7 2.4.1. What is Building Energy Modelling? ................................................................... 7 2.4.2. Visual Introduction to BEM and its Features ....................................................... 7 3.0 Advances in Energy Modelling ....................................................................................... 9 3.1. Integration Processes and Techniques ......................................................................... 9 3.1.1. Conversion from BIM to BEM ........................................................................... 10 3.1.2. Current Integration Processes ............................................................................. 10 3.2. Current Errors and Limitations in Integration ........................................................... 13 3.2.1. Current Integration Techniques Hinderances ..................................................... 13 3.2.2. Limitations in the Modelling Procedure ............................................................. 14 3.3. Project Specific Advances in Energy Modelling ....................................................... 15 3.3.1. The Gap in the Process ....................................................................................... 15 4.0 Project Execution ........................................................................................................... 17 4.1. Project Plan ................................................................................................................ 17 4.2. Testing of processes for conversion ........................................................................... 18 4.2.1. Model One – Simple Box: .................................................................................. 18 4.2.2. Model Two – Single floor with complex walls: ................................................. 20 4.3. Creation and Preparation of a Revit BIM Model ....................................................... 22 iv | P a g e 4.3.1. Model Three – 69 Robertson Street Building:.................................................... 22 4.4. Convert the prepared Revit Model to OpenStudio .................................................... 25 4.5. Compare BI-EM, BEM, and BIM-BEM ................................................................... 27 4.5.1. Software used ....................................................................................................