Import a Model or Drawing

Darwin can take quantities from two kinds of source input: a 3D IFC model, or a 2D drawing — a PDF or an image (JPG, PNG) of a plan. Both accelerate quantity takeoff (QTO) the same way: Darwin extracts geometry or measurements, organizes them, and prepares them so you can map them to cost modules.

This entire step is optional. Manual quantity entry is the default in Darwin — you can build a complete estimation by typing in quantities yourself, no model or drawing required. Import a model or drawing only when one is available and you want to move faster.

1. This Step Is Optional

If you don’t have an IFC model or a 2D drawing, skip this chapter entirely and continue with manual estimation — Darwin works fully either way.

If you do have one, importing it doesn’t hand control to the model. Darwin uses it as input: geometry and measurements, not a source of truth. The estimator still decides how objects map to cost logic.

2. Two Ways to Bring In Design Data

	3D IFC Model	2D Drawing (PDF / Image)
Best for	Projects with a coordinated BIM model	Concept sketches, scanned plans, drawings without a model
What you upload	An `.ifc` file	A PDF or image (JPG, PNG)
What Darwin extracts	Walls, slabs, columns, doors, windows, beams, MEP components	Measured quantities you draw or annotate — length, area, count
Scale	Comes from the model	You calibrate scale against a known dimension
Viewer	3D IFC Viewer	2D QTO canvas

Both paths end at the same place: quantities ready to map to modules. Use whichever one matches what you actually have.

3. Importing an IFC Model

Open your Project.
Open the project’s QTO Sessions area.
Start a project IFC import and upload your .ifc file.
Review the new import session while it is in progress.

Darwin creates an IFC Import Session and processes the model:

Reading the model — Darwin loads the IFC and validates its structure
Extracting elements — identifies objects such as walls, slabs, columns, doors, windows, beams, and MEP components
Grouping and classifying — groups elements by type, layer, or category so they can be mapped to modules
Enriching elements with metadata — prepares each element with the information needed for mapping and quantity extraction

Once the import is complete, open the IFC Viewer to rotate, pan, and inspect the model in 3D, isolate object types, visualize quantities such as length, area, and volume, and click elements to view metadata.

4. Importing a 2D Drawing (PDF or Image)

No BIM model? A scanned plan, a PDF export, or a photo of a drawing works too.

Open your Project.
Open the project’s QTO Sessions area and start a 2D session.
Upload your PDF or image file.
Calibrate the scale by marking a known dimension on the drawing (e.g., a wall length or a dimension line).
Use the 2D QTO canvas to measure or annotate the quantities you need — lengths, areas, counts.

Each measurement you draw becomes a quantity Darwin can map to a module or material, the same way an IFC-extracted quantity does. You control exactly what gets measured and how it’s classified.

5. Understanding Import Sessions

Whether you import an IFC model or a 2D drawing, Darwin creates an Import Session — a record that tracks the entire lifecycle of that source file. A session:

records the uploaded file
stores extracted or measured quantities
tracks classifications
preserves mapping history
allows reprocessing if needed

You can have multiple sessions per project — useful for design revisions, alternative scenarios, or drawings that arrive in phases.

6. When to Use a Model or Drawing in Estimation

Use IFC or 2D import when you:

want fast quantity takeoff
have a well-structured BIM model, or a clear plan/PDF to measure from
need visual verification of elements or measurements
want consistency between design and cost

If the model is incomplete, the drawing is messy, or you simply don’t have one, manual quantities work just as well. Darwin does not depend on BIM or 2D drawings — they simply accelerate the process when available.

For a quick file inspection with no project record, use a standalone QTO viewer instead. Standalone measurements are not saved to the project and cannot be handed off into an estimate. See Work With QTO Sessions before choosing a workspace.

7. Next Step

After importing your model or drawing, the next step is to connect what you extracted or measured to cost logic:

➡️ Map Elements to Modules