Export model items to IFC

Goal: write a chosen set of model items to an .ifc file, with names you set for the project, site, building and storey.

Before you start

• Open a model in Navisworks and the CamelGraph editor.
• The IFC export engine ships inside CamelGraph. You do not need another plug-in.
• Decide where the file goes and use a full path that ends in .ifc, for example C:\Exports\level-02.ifc. The folder is created if it is missing.

Download the graph

Steps

1. Add a String node (Input), rename it Level to export and type Level 02. Add Search.ByProperty (Navisworks ▸ Search) to choose what to export: categoryName = Element, propertyName = Level, mode = equals, and wire the String into value. Use a level name from your model.
2. Add Export.ToIfc (Navisworks ▸ Export). Wire the search items into its items. Type the full path into filePath. Only items and filePath are required.
3. Add Export.IfcSpatialNames (Navisworks ▸ Export). Type names into project, site, building and storey, for example Office Block, Main Site, Block A and Level 02. Wire its spatialNames output into the spatialNames input of Export.ToIfc.
4. Add Export.IfcCoordinates (Navisworks ▸ Export). Leave basePoint on GeometryOrigin for now. Wire its coordinates output into the coordinates input of Export.ToIfc.
5. Add a Watch (Display), rename it Elements exported and wire elementCount into it. You can add more for fileCount and fileSizeKb.
6. Switch Auto off in the run bar, then press F5. The export reads the geometry of every item and can take a while on a large model.

The IFC export graph: a search into Export.ToIfc, with Export.IfcSpatialNames and Export.IfcCoordinates wired into it.

What you get

An IFC file with a spatial tree, geometry (repeated shapes reused as mapped items to keep the file small), property sets, materials, base quantities and, for IFC4, georeferencing. The outputs filePath, fileCount, elementCount, triangleCount and fileSizeKb tell you what was written.

Useful options

Input	Default	Use it to
schema	IFC4	Write IFC2x3 instead.
instancing	on	Switch off to write every mesh in full.
properties, materials, quantities	on	Leave out property sets, materials or base quantities.
units	Auto	Force Millimeters, Centimeters, Meters, Feet or Inches if the model's units are wrong.
quality	Balanced	Choose Small file or High detail.
splitMegabytes	0	Split the output into parts near this size. 0 is one file.
validate	off	Run the built-in structural check on each file written.

Export.IfcCoordinates also takes Custom for basePoint, with eastings, northings and elevation in metres, a rotationDegrees and a writeGeoref switch. Export.IfcSetClassMap gives items an IFC class by set name, and Export.IfcRoles and Export.IfcParameterRule map properties to IFC roles and rename them. All are described in IFC, BCF, Excel and CSV.

One file for each group

To write several IFC files from one graph, use one Export.ToIfc for each file, or put it between Loop.Item and Loop.Collect.

If it does not work

• The file is not written: see A file node fails with "access denied".
• Export.ToIfc says "No geometry elements to export": the search found no items, or none with geometry. See A search returns nothing.
• Export.ToIfc says the path "must end in .ifc": fix the file name.
• With validate on, the node fails and lists the issues the checker found.
• The export is slow: see Speed up a slow graph.

Next

• Send clashes to BCF.
• Export nodes lists every input and output.
• Privacy and safety: export nodes write files, so the Player asks before it runs a script that has one.