The conversion of a Building Information Model (BIM) to a Building Energy Model (BEM) has typically been technically challenging. While BIM platforms like Revit provide architects and engineers with sophisticated design tools, these models are rarely used directly for energy simulation.
Key Challenges in BIM-to-BEM Workflows
- Loss of geometry and metadata
- Misalignment of room boundaries, leading to overlapping or missing thermal zones
- Incorrect classification of elements and openings (e.g., windows being treated as walls)
- Shading and context inconsistencies, affecting solar radiation and daylight modeling
- High workload in error correction
Pollination: BIM-to-BEM Interoperability Framework
Pollination is an ecosystem of tools that benefits the user by:
- Ensuring accurate geometry exports from Revit and Rhino
- Reducing manual rework by allowing model validation before export
- Providing precise shading controls
- Facilitating collaboration through cloud-based workflows
Pollination achieves this through two key workflows, each designed to optimize BIM-to-BEM translation.
Workflow 1: Direct Revit to IES-VE Integration
Pollination provides a direct GEM-based export workflow.
Key Features of the Revit-to-IES-VE Workflow
- Native GEM Format Export
- Intelligent Adjacency Detection
- Customizable openings and Shading Controls
- Built-in Model Validation and Error Detection
How it Works:
1. Export from Revit – Use Pollination’s Revit Plugin to configure room boundaries, openings, and shading, then export as a GEM file.
2. Import into IES-VE – Load the GEM file into IES-VE, ensuring accurate adjacency, zoning, and opening placement.
3. Validate & Simulate – Review the imported model, make final adjustments if needed, and proceed with energy simulation.
Why This Matters
- Reduces geometry errors after export
- Minimizes manual cleanup time by providing an error-free analytical model
- Greater simulation accuracy
Workflow 2: Revit to Rhino to IES-VE for Advanced Model Control
While the direct Revit-to-IES-VE workflow works for most users, advanced projects often require more refined geometry manipulation. In such cases, Pollination enables an HPJson-based workflow where models are first transferred from Revit to Rhino, allowing for additional adjustments before export.
Why Use Rhino as an Intermediary?
- Fine-tune geometry and resolve misalignments
- Optimize computational height settings for accurate section cuts
- Clean up complex curtain walls and apertures
- Simplify shading elements to reduce simulation complexity
How It Works
1. Export from Revit – Use Pollination’s Revit Plugin to export the model as HPJson, preserving room boundaries, windows, and shading.
2. Refine in Rhino – Clean up geometry, align misaligned spaces, simplify shading, and validate the analytical model.
3. Export to IES-VE – Convert the refined Rhino model to GEM format, import into IES-VE, and proceed with simulation.
Advantages of the Revit → Rhino → IES-VE Workflow
- Ensures high geometric fidelity
- Reduces processing time in IES-VE
- Eliminates unnecessary data bloat
- Provides greater control over model adjustments
Technical Enhancements: What Sets Pollination Apart
Beyond good interoperability, Pollination integrates advanced data science and computational geometry algorithms to enhance BIM-to-BEM workflows.
1. Automated Adjacency & Surface Cleaning
Pollination utilizes computational geometry techniques to:
- Merge redundant faces, reducing unnecessary complexity in IES-VE models
- Resolve adjacency conflicts by intelligently aligning surfaces
- Automatically detect & fix overlapping rooms, preventing simulation errors
2. Parametric Aperture & Shading Control
Pollination provides granular control over apertures:
- Option 1: Directly export individual windows
- Option 2: Use window-to-wall ratio (WWR) simplifications
- Option 3: Parametric generation of custom shading devices in Rhino
3. Large-Scale Model Handling
Unlike traditional gbXML exporters, Pollination has no built-in room/zone limits.
- Successfully tested on projects with 2000+ rooms (e.g., hospital buildings)
- Supports multi-level data processing, ensuring smooth handling of complex geometries
Efficiency Gains:
- 50-80% reduction in manual rework
- Elimination of geometry-related import errors
- More accurate simulations leading to better energy modeling
Utilise Pollination Now
For professionals looking to streamline their workflows, eliminate rework, and enhance energy modeling accuracy, Pollination can help. To find out more, join our free webinar on 7th May 2025 at 2pm BST / 9am EDT or contact our team.
