Architecture and construction
Extract Structured Data from Construction Drawings and Project Documents
Construction drawing extraction converts readable content from uploaded PDF, JPEG, or PNG files into fields that teams can inspect: project and drawing identifiers, locations, spaces, materials, dimensions, notes, approvals, and warnings. toSchema’s current architectural template returns structured JSON; it does not modify CAD or BIM models.
Updated August 28, 2026
Start with drawing identity and revision
A construction record is only useful when it remains attached to the correct project, drawing, date, scale, and revision. The current architectural schema can represent project and drawing numbers, title and type, drawing and revision dates, scale, architect and client details, project location, and broad building information.
Extract these fields before schedules or notes. A room area copied from revision R1 should not silently replace the value shown in R2. The source file and title block remain the authority, especially when a drawing set contains superseded sheets.
- Keep project number, drawing number, and revision together as the review key.
- Preserve units beside areas, elevations, heights, and dimensions.
- Record the drawing scale as text rather than treating it as measured geometry.
- Check title-block dates and approval marks against the visible sheet.
Structure schedules and notes without erasing context
The architectural template includes arrays for spaces, materials, dimensions, notes, approvals, signage, references, and warnings. These records can help a reviewer find named rooms, finishes, dimension labels, or approval statements across a document.
A parsed label is not the same as a geometric relationship. OCR may read a dimension while missing the line or element it applies to. Cropped drawings, rotated annotations, dense legends, and references to other sheets all limit what a standalone extraction can establish.
Treat structured JSON as a review handoff
The output can support document indexing, register preparation, or a manual handoff into another system. Reviewers should compare high-impact fields with the current source and confirm that the revision belongs to the intended project package.
toSchema does not currently compare revisions, calculate quantities, make a code-compliance decision, or write into CAD or BIM software. Geometry, model objects, and multidisciplinary coordination remain outside the current architectural extraction contract.
Illustrative example
Example architectural drawing excerpt
This excerpt comes from the fixture used by the current architectural schema and shows how sheet metadata and one space can remain separate.
Illustrative title block and room label
Riverfront Mixed-Use Development Drawing A-103 · Revision R2 · Scale 1:100 Unit 201 · Level 2 · 950 sq.ft
Structured drawing excerpt
{
"metadata": {
"projectName": "Riverfront Mixed-Use Development",
"projectNumber": "ARK-2024-0142",
"drawingType": "Floor Plan",
"drawingNumber": "A-103",
"drawingTitle": "Second Floor Plan - Residential Units",
"drawingDate": "2024-01-15",
"revisionNumber": "R2",
"revisionDate": "2024-02-28",
"scale": "1:100"
},
"space": {
"name": "Unit 201",
"function": "2-Bedroom Apartment",
"area": 950,
"areaUnit": "sq.ft",
"level": "2"
}
}This is an illustrative excerpt from the current architectural fixture, not a BIM object or takeoff result.
Limitations
- OCR cannot recover cropped, blurred, obscured, or visually ambiguous drawing details.
- Extracted labels and dimensions do not reproduce drawing geometry, spatial relationships, or a BIM model.
- Revision comparison, quantity takeoff, compliance decisions, and CAD or BIM writeback are not included.
Frequently asked questions
Which construction-document fields are supported?
The architectural template can represent project and drawing metadata, parties, location, building details, spaces, materials, dimensions, notes, approvals, signage, references, and warnings when those details are readable in the source.
Can scanned construction drawings be analyzed?
Readable PDF, JPEG, and PNG scans can be analyzed, but rotation, scale, line work, dense callouts, and cross-sheet references can make labels ambiguous. Review the result against the current drawing revision.
Does toSchema export a CAD or BIM model?
No. The current architectural route returns structured JSON from document content. It does not reconstruct geometry, create model objects, or write changes into CAD or BIM tools.
Put it into practice