Work With QTO Sessions
import DocCallout from ‘../../../components/DocCallout.astro’;
Choose Standalone or Project-Backed QTO
Section titled “Choose Standalone or Project-Backed QTO”| If you need to… | Use… | What Darwin keeps |
|---|---|---|
| Inspect an IFC, PDF, or image without creating project work | A standalone QTO viewer | Local browser cache only |
| Measure a drawing or map an IFC for an estimate | A project QTO session | A project-linked session, measurements, and mappings |
Standalone viewers are useful for a quick first look. You can inspect a model, calibrate a drawing, take measurements, and export results. They do not save to the project or create an estimate. If a file becomes estimate-worthy, open it again from the project’s QTO Sessions area and start a project session.
Work With a Project 2D Session
Section titled “Work With a Project 2D Session”Use a project 2D session for a PDF or image that needs durable takeoff.
- Open the project’s QTO Sessions area and start or resume the 2D session.
- In Takeoff, calibrate the scale against a known dimension for each drawing page you measure.
- Draw or edit areas, rectangles, linear measurements, counts, annotations, or auto-count results.
- Confirm the autosave indicator reports Saved.
- Switch to Mapping and connect measurements to the appropriate module or material.
Takeoff edits and mapping edits are saved separately. A Saving indicator means Darwin is still persisting work. An Error indicator means the latest save failed, so the unsaved edits remain only in the current browser session until saving succeeds.
Work With a Project IFC Session
Section titled “Work With a Project IFC Session”Use a project IFC session when a 3D model needs to generate estimate quantities.
- Start an IFC import from the project’s QTO Sessions area and upload the
.ifcfile. - Review the import session while it is In Progress.
- Map each layer in bulk to an existing module, a new module, or a material.
- Add an individual element override only when the layer needs an exception.
- Generate the estimation after the mappings are ready.
An individual override changes that layer from bulk mapping to individual mapping. When generation succeeds, Darwin creates an IFC-generated estimation and marks the import session Completed.
Use Quantities in the Estimate
Section titled “Use Quantities in the Estimate”Project-backed mappings make quantities available in Estimation Details. Their provenance shows whether a quantity was entered manually, captured through 2D QTO, or derived from IFC. Review that source before approval, especially when a design file has changed.