Can I add a property that does not exist in the model?

Yes. You can create a new Pset or a new property inside an existing one and apply it to the elements you choose; it is written into the IFC as an IfcPropertySingleValue inside its IfcPropertySet.

How do I apply the same value to hundreds of elements?

With batch editing: choose the target (a whole IFC type, the result of a filter, a GUID list or the 3D selection), set Pset, property and value, and apply once.

Can I check which properties are missing before delivering?

Yes. Load your required-property template in Excel and the model is validated against it: you see which elements fail and can add the missing columns to the panel.

Do I need Revit or the original authoring tool?

No. Everything happens in the browser on the IFC file itself, so it works for models made in Revit, Allplan, ArchiCAD, Civil 3D or Istram.

How to add properties to an IFC file

Filling in a control property — phase, contract, asset code, subsystem — across hundreds of elements is one of the biggest time sinks in a BIM job. This guide solves it from the browser, on the IFC itself, without opening the authoring tool.

Open my IFC — free What else can be edited

Step by step

Open the IFC. Drag it onto geomaifc.com/app. It is processed on your machine; nothing is uploaded.
Choose who it affects. Filter by IFC type (IFCWALL, IFCPIPESEGMENT…), by text, by another property's value or by chainage; or select the elements directly in the 3D view.
Set Pset, property and value. Use an existing Pset or create a new one, same for the property. It is written as an IfcPropertySingleValue inside its IfcPropertySet.
Apply. The change hits the whole selection at once. Ctrl+Z undoes the last edit.
Download the modified IFC. Your original file is untouched: you get a copy with the properties added.

Four ways to choose the target

Target	When to use it
By IFC type	"All walls get Phase = F2". One or several types at once.
By filter	Whatever survives filtering by text, property or chainage range: the usual case in linear works.
By GUID list	When the property comes from a spreadsheet holding the model's GUIDs.
By 3D selection	What you picked in the viewer, window selection included.

Checking what is missing before you deliver

If the brief comes with a list of required properties, load it as an Excel template: the model is validated against it and you see which elements fail, with the option to add the missing columns to the panel and fill them right there. That is the difference between delivering and having the model bounced back.

When you need quantities rather than control properties — volumes, areas, lengths — use the automatic quantity take-off, ready for Excel.

Mistakes worth avoiding

Writing the property into the wrong Pset. A software-native Pset_ is no place for control data: use the project Pset the brief asks for.
Mixing units or date formats between batches: the recipient will catch it on validation and you get to do it twice.
Changing properties without checking in 3D. Select and isolate the batch before applying — you see at once if the filter caught too much.

Frequently asked questions

Can I add a property that does not exist yet?: Yes, by creating the Pset or the property on the fly and applying it to the selection.
Do I need Revit or the original tool?: No: you work on the IFC, whether it came from Revit, Allplan, ArchiCAD, Civil 3D or Istram.
Is my original file modified?: No. Changes materialise when you press "Download IFC", which gives you a copy.
Is this free?: Opening and inspecting the model is. Batch editing is in the paid plans, from €19/month. See plans.

Add properties now Merge two IFC files