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LocusBIM User Guide

PDF Markup Engine · 3D Viewer · Coordination Tools

Everything you need to mark up construction PDFs, coordinate 3D BIM models, run cost takeoffs, and collaborate with your team. Pick a topic to get started.

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Khatam

Khatam — Overview
The AEC-domain AI engine that powers LocusBIM. On-device, no cloud, no per-inference billing. The purple khatam mark, the glow/spin interaction pattern, and what Khatam does today.
Khatam — Markup intelligence
How Khatam helps with markups: canonical phrase suggestions, semantic search, similar-markup detection, the markup insights row, Organize layers, Style audit, conversational filter, and markup-to-RFI drafts.
Khatam — Coordination & review
Khatam for coordination: semantic diff between drawing revisions, the cross-sheet consistency check that flags plan-vs-schedule mismatches, and LocusSync session summaries.
Khatam — Cost intelligence
Khatam in the cost engine: semantic CSI cost-code matching when no exact category fits, and the aggregate confidence indicator that surfaces low-confidence cost rows for a second look.
Khatam — About
How Khatam was built, the on-device privacy promise and opt-in telemetry (PIPEDA, Canadian data residency), the roadmap, and why it is named Khatam.

Mark up drawings

Markup Tools
Rectangle, ellipse, cloud, text, freehand, highlight, and cutout tools for marking up PDF construction drawings.
Drawing Tools
Arrow, callout, polyline, polygon, arc, image, spline, and leader tools for detailed PDF markup.
Format
Stroke colour, fill, line style, opacity, line width, and font controls applied to selected markups.
Layers
Organise markups into named layers — hide, lock, or reassign markups per discipline or markup pass.
Symbols Library
Industry symbol library — electrical, plumbing, HVAC, fire/safety, structural, civil, medical, lab, and architectural symbols.
Signatures & Stamps
Apply professional engineer signatures, project stamps, and approved/rejected markups to PDF drawings.
Markup Comments
Add threaded comments and discussion replies to any markup on a PDF drawing — saved locally and shared via LocusSync.
Find Text & OCR
Cross-page Ctrl+F text search plus on-device OCR for scanned PDFs in English and French — your drawings never leave your machine.

Measure and calibrate

Cost Impact

Cost Impact — Overview
Live rough-order-of-magnitude cost estimates as you mark up PDFs and 3D issues: first-time setup (calibrate scale), how it works, and the core budgeting workflows.
Cost Impact — What triggers costs
Which markup tools produce cost rows, why a calculation looks wrong or missing, smart scope detection, and the best-practice workflow for accurate estimates.
Cost Impact — Element types & mapping
How markups map to CSI cost codes: IFC type mapping for 3D, mapping your own Revit categories, and setting element type on generic PDFs.
Cost Impact — AI-assisted costing
Khatam in the cost engine: the confidence indicator, manual override, intelligent takeoff from symbols and hatches, the MEP keyword hint, and the AI verbiage helper.
Cost Impact — Configuration & reference
Cost Impact configuration: toolbar controls, region factor (city multipliers), imperial vs metric units, custom cost items, CSV import/export, and the legal disclaimer.

Work with documents

3D model coordination

3D Viewer Tools
Model tree visibility, category filtering, level isolation, element search, fly-to navigation, saved views, and lighting presets in the 3D BIM viewer. Section Box, Orthographic Views, and Explode View have their own pages.
Section Box & Clipping
Clip the 3D BIM model to a rectangular region using six hardware-accelerated clipping planes — reveal interior spaces, isolate a single floor, or examine structural details without moving the camera.
Orthographic Views & Sections
Snap the 3D camera to standard top, front, side, or back orthographic views, and generate scaled IFC-direct section drawings with line-weight hierarchy and material hatching.
Explode View
Radially separate every element in the 3D model from the scene centroid — see what's behind walls, document construction sequencing, or review MEP routing without hiding categories one at a time.
Link PDF to 3D
Calibrate a 2D sheet to its 3D model coordinates so clicking a markup flies the 3D viewer to the matching element, and vice versa.
Issue Tracking
Track RFIs, clashes, and coordination issues with AI-suggested categories and urgency tags, plus full BCF 2.1 round-trip.
IFC Element Matching
Match Revit and IFC element identifiers across model versions so issues and markups stay linked when the model is rebuilt.
Issue Comments
Threaded discussion on every 3D viewer issue — saved locally, synced live across LocusSync sessions.

Team collaboration

CAD app plugins

Account

Accessibility