BEMTrace: Visualization-driven approach for deriving Building Energy Models from BIM

TL;DR

This paper addresses the challenge of deriving valid BEM representations from BIM data for energy simulations, where BIM quality issues hinder accurate thermal analysis. It introduces BEMTrace, a visualization-driven workflow with five interconnected views (BIM World, BEM World, Relationship View) and context-adaptive selections to trace and validate the BIM-to-BEM conversion. The approach combines 3D data wrangling, automated error detection and correction, and interactive visualization to improve transparency and trust in the conversion process. Evaluation through task analysis, heuristic evaluation, and qualitative feedback from domain experts demonstrates usefulness for expert users and identifies directions for future improvements in scalability and display.

Abstract

Building Information Modeling (BIM) describes a central data pool covering the entire life cycle of a construction project. Similarly, Building Energy Modeling (BEM) describes the process of using a 3D representation of a building as a basis for thermal simulations to assess the building's energy performance. This paper explores the intersection of BIM and BEM, focusing on the challenges and methodologies in converting BIM data into BEM representations for energy performance analysis. BEMTrace integrates 3D data wrangling techniques with visualization methodologies to enhance the accuracy and traceability of the BIM-to-BEM conversion process. Through parsing, error detection, and algorithmic correction of BIM data, our methods generate valid BEM models suitable for energy simulation. Visualization techniques provide transparent insights into the conversion process, aiding error identification, validation, and user comprehension. We introduce context-adaptive selections to facilitate user interaction and to show that the BEMTrace workflow helps users understand complex 3D data wrangling processes.

Figures (12)

• Figure 1: The BIM-to-BEM conversion process describes converting a BIM model to a BEM model. The novel contributions of this paper lie in the area highlighted in red.
• Figure 2: Building Energy Modeling (BEM) allows engineers to run complex physical simulations to study a room's temperature under different conditions. In this example, temperatures without (a) and with (b) cooling in place are compared. Image taken from Charvátová et al. CharPZ18.
• Figure 3: Thermal simulations in BEM rely on watertight arrangements of space boundaries. Since surfaces in BIM are not always watertight, data preprocessing involves removing recesses and appropriately enlarging surfaces between rooms.
• Figure 4: Space boundaries define connecting surfaces between two rooms. A wall element may consist of more than one space boundary, as shown in this illustration. Figure parts taken from buildingSMART bs24.
• Figure 5: In BIM, a Building is composed of Building Storeys, which are further composed of Building Elements, Spaces, and Space Boundaries. We follow this notion and division of BIM structures in our application. Images taken from Malhotra et al. MalhBNHESAFVOS22.