rvt-to-ifc

RVT to IFC Conversion

Note: RVT is the file format. IFC is an open standard by buildingSMART International.

Business Case

Problem Statement

IFC is the open BIM standard for interoperability, but:

• Native Revit IFC export requires Autodesk license
• Export settings significantly affect data quality
• Batch processing is manual and time-consuming

Solution

RVT2IFCconverter.exe converts Revit files to IFC offline, without licenses, with full control over export settings.

Business Value

• No license required - Works without Autodesk software
• Multiple IFC versions - IFC2x3, IFC4, IFC4.3 support
• Batch processing - Convert thousands of files
• Consistent quality - Standardized export settings

Technical Implementation

CLI Syntax

RVT2IFCconverter.exe <input.rvt> [<output.ifc>] [preset=<name>] [config="..."]

IFC Versions

Version	Use Case
IFC2x3	Legacy compatibility, most software
IFC4	Enhanced properties, modern BIM
IFC4.3	Infrastructure, latest standard

Export Presets

Preset	Description
standard	Default balanced export
extended	Maximum detail and properties
custom	User-defined configuration

Examples

# Standard IFC export
RVT2IFCconverter.exe "C:\Projects\Building.rvt"

# IFC4 with extended settings
RVT2IFCconverter.exe "C:\Projects\Building.rvt" preset=extended

# Custom output path
RVT2IFCconverter.exe "C:\Projects\Building.rvt" "D:\Export\model.ifc"

# Custom configuration
RVT2IFCconverter.exe "C:\Projects\Building.rvt" config="ExportBaseQuantities=true; SitePlacement=Shared"

Python Integration

import subprocess
from pathlib import Path
from typing import List, Optional, Dict, Any
from dataclasses import dataclass
from enum import Enum


class IFCVersion(Enum):
    """IFC schema versions."""
    IFC2X3 = "IFC2x3"
    IFC4 = "IFC4"
    IFC4X3 = "IFC4x3"


class ExportPreset(Enum):
    """Export presets."""
    STANDARD = "standard"
    EXTENDED = "extended"
    CUSTOM = "custom"


@dataclass
class IFCExportConfig:
    """IFC export configuration."""
    ifc_version: IFCVersion = IFCVersion.IFC4
    export_base_quantities: bool = True
    site_placement: str = "Shared"
    split_walls_and_columns: bool = False
    include_steel_elements: bool = True
    export_2d_elements: bool = False
    export_linked_files: bool = False
    export_rooms: bool = True
    export_schedules: bool = True

    def to_config_string(self) -> str:
        """Convert to CLI config string."""
        parts = [
            f"ExportBaseQuantities={str(self.export_base_quantities).lower()}",
            f"SitePlacement={self.site_placement}",
            f"SplitWallsAndColumns={str(self.split_walls_and_columns).lower()}",
            f"IncludeSteelElements={str(self.include_steel_elements).lower()}",
            f"Export2DElements={str(self.export_2d_elements).lower()}",
            f"ExportLinkedFiles={str(self.export_linked_files).lower()}",
            f"ExportRooms={str(self.export_rooms).lower()}"
        ]
        return "; ".join(parts)


class RevitToIFCConverter:
    """Convert Revit files to IFC format."""

    def __init__(self, converter_path: str = "RVT2IFCconverter.exe"):
        self.converter = Path(converter_path)
        if not self.converter.exists():
            raise FileNotFoundError(f"Converter not found: {converter_path}")

    def convert(self, rvt_file: str,
                output_path: Optional[str] = None,
                preset: ExportPreset = ExportPreset.STANDARD,
                config: Optional[IFCExportConfig] = None) -> Path:
        """Convert Revit file to IFC."""

        rvt_path = Path(rvt_file)
        if not rvt_path.exists():
            raise FileNotFoundError(f"Revit file not found: {rvt_file}")

        # Build command
        cmd = [str(self.converter), str(rvt_path)]

        # Add output path if specified
        if output_path:
            cmd.append(output_path)

        # Add preset
        cmd.append(f"preset={preset.value}")

        # Add custom config if provided
        if config:
            cmd.append(f'config="{config.to_config_string()}"')

        # Execute
        result = subprocess.run(cmd, capture_output=True, text=True)

        if result.returncode != 0:
            raise RuntimeError(f"Conversion failed: {result.stderr}")

        # Return output path
        if output_path:
            return Path(output_path)
        return rvt_path.with_suffix('.ifc')

    def batch_convert(self, folder: str,
                      output_folder: Optional[str] = None,
                      preset: ExportPreset = ExportPreset.STANDARD,
                      config: Optional[IFCExportConfig] = None) -> List[Dict[str, Any]]:
        """Convert all Revit files in folder."""

        folder_path = Path(folder)
        results = []

        for rvt_file in folder_path.glob("**/*.rvt"):
            try:
                # Determine output path
                if output_folder:
                    out_dir = Path(output_folder)
                    out_dir.mkdir(parents=True, exist_ok=True)
                    output_path = str(out_dir / rvt_file.with_suffix('.ifc').name)
                else:
                    output_path = None

                ifc_path = self.convert(str(rvt_file), output_path, preset, config)
                results.append({
                    'input': str(rvt_file),
                    'output': str(ifc_path),
                    'status': 'success'
                })
                print(f"✓ Converted: {rvt_file.name}")

            except Exception as e:
                results.append({
                    'input': str(rvt_file),
                    'output': None,
                    'status': 'failed',
                    'error': str(e)
                })
                print(f"✗ Failed: {rvt_file.name} - {e}")

        return results

    def validate_output(self, ifc_file: str) -> Dict[str, Any]:
        """Basic validation of generated IFC."""

        ifc_path = Path(ifc_file)
        if not ifc_path.exists():
            return {'valid': False, 'error': 'File not found'}

        # Basic file checks
        file_size = ifc_path.stat().st_size

        if file_size < 1000:
            return {'valid': False, 'error': 'File too small'}

        # Read header
        with open(ifc_file, 'r', errors='ignore') as f:
            header = f.read(1000)

        # Check IFC format
        if 'ISO-10303-21' not in header:
            return {'valid': False, 'error': 'Not a valid IFC file'}

        # Detect version
        version = 'Unknown'
        if 'IFC4X3' in header:
            version = 'IFC4.3'
        elif 'IFC4' in header:
            version = 'IFC4'
        elif 'IFC2X3' in header:
            version = 'IFC2x3'

        return {
            'valid': True,
            'file_size': file_size,
            'ifc_version': version
        }


class IFCQualityChecker:
    """Check quality of IFC exports."""

    def __init__(self, converter: RevitToIFCConverter):
        self.converter = converter

    def compare_presets(self, rvt_file: str) -> Dict[str, Any]:
        """Compare different export presets."""

        results = {}

        for preset in [ExportPreset.STANDARD, ExportPreset.EXTENDED]:
            try:
                output = Path(rvt_file).with_suffix(f'.{preset.value}.ifc')
                self.converter.convert(rvt_file, str(output), preset)

                validation = self.converter.validate_output(str(output))
                results[preset.value] = {
                    'file_size': validation.get('file_size', 0),
                    'valid': validation.get('valid', False)
                }
            except Exception as e:
                results[preset.value] = {'error': str(e)}

        return results


# Convenience functions
def convert_revit_to_ifc(rvt_file: str,
                         converter_path: str = "RVT2IFCconverter.exe") -> str:
    """Quick conversion of Revit to IFC."""
    converter = RevitToIFCConverter(converter_path)
    output = converter.convert(rvt_file)
    return str(output)


def batch_convert_to_ifc(folder: str,
                         converter_path: str = "RVT2IFCconverter.exe") -> List[str]:
    """Batch convert all Revit files to IFC."""
    converter = RevitToIFCConverter(converter_path)
    results = converter.batch_convert(folder)
    return [r['output'] for r in results if r['status'] == 'success']

Quick Start

# Initialize converter
converter = RevitToIFCConverter("C:/DDC/RVT2IFCconverter.exe")

# Basic conversion
ifc = converter.convert("building.rvt")
print(f"Created: {ifc}")

# With custom config
config = IFCExportConfig(
    ifc_version=IFCVersion.IFC4,
    export_base_quantities=True,
    export_rooms=True
)
ifc = converter.convert("building.rvt", preset=ExportPreset.CUSTOM, config=config)

Common Use Cases

1. Batch Processing

converter = RevitToIFCConverter()
results = converter.batch_convert(
    folder="C:/Projects",
    output_folder="C:/IFC_Export",
    preset=ExportPreset.EXTENDED
)
print(f"Converted {len([r for r in results if r['status'] == 'success'])} files")

2. Quality Check

validation = converter.validate_output("model.ifc")
print(f"Valid: {validation['valid']}, Version: {validation['ifc_version']}")

3. Compare Presets

checker = IFCQualityChecker(converter)
comparison = checker.compare_presets("building.rvt")
print(comparison)

Resources

• GitHub: cad2data Pipeline
• buildingSMART IFC: https://www.buildingsmart.org/standards/bsi-standards/industry-foundation-classes/