Drawing Comparison

Summary: Bedrock’s drawing comparison automatically matches sheets, aligns drawings, and detects changes between revisions. Upload two drawing sets and get detailed change analysis in minutes.

How It Works

  1. Upload two drawing sets (prior revision and current revision)
  2. Match - AI automatically matches corresponding sheets
  3. Align - Drawings are aligned without manual point selection
  4. Detect - Changes are identified and categorized
  5. Export - Download overlays and change reports

A 500-sheet comparison takes minutes, not hours.

Features

FeatureDescription
Automatic Sheet MatchingAI matches sheets between revisions even when sheet numbers change
Auto AlignmentNo manual 3-point alignment required
Change DetectionIdentifies additions, deletions, and modifications
Change CategorizationLabels changes by type (dimension, text, graphic)
Cost Impact EstimationEstimates labor and material impact of changes
Batch ProcessingCompare entire drawing sets in one operation
PDF ExportStandard overlays compatible with any workflow

Comparison Methods

Bedrock offers multiple visualization options:

MethodBest For
Color OverlayQuick visual scan of all changes
Side-by-SideDetailed comparison of specific areas
Change ListSystematic review of categorized changes
Cost ReportStakeholder communication on impact

Supported Drawing Types

DisciplineExamples
ArchitecturalFloor plans, elevations, sections, details
StructuralFraming plans, foundation plans, details
MEPMechanical, electrical, plumbing layouts
CivilSite plans, grading, utilities

Technical Specifications

SpecificationValue
Maximum Set Size1,000+ pages per set
Supported FormatPDF
Minimum Sheet SizeLetter (8.5” x 11”)
Maximum Sheet SizeARCH E (36” x 48”)
Output FormatsPDF overlay, CSV report

Processing Speed

Set SizeTypical Time
50 sheets2-3 minutes
200 sheets5-8 minutes
500 sheets12-15 minutes
1,000 sheets25-30 minutes

Times vary based on drawing complexity and change density.

What Gets Detected

Bedrock detects changes across all drawing elements:

  • Dimensions: Changed measurements, added/removed dimensions
  • Text: Spec changes, notes, callouts
  • Graphics: Lines, shapes, hatching, symbols
  • Annotations: Revision clouds, tags, leaders

What Doesn’t Get Detected

Some elements are filtered to reduce noise:

  • Title block updates (dates, revision numbers)
  • Watermarks and stamps
  • Minor PDF rendering differences
  • Color profile changes

Integration

Bedrock outputs work with your existing tools:

  • Bluebeam: Import overlays for additional markup
  • Procore: Attach reports to RFIs and change orders
  • Email: Share PDFs directly with stakeholders
  • File Storage: Export to any folder or cloud drive

FAQ

How accurate is the change detection?

Bedrock detects changes at the pixel level. Accuracy exceeds 99% for graphic elements. Text detection accuracy depends on PDF text layer quality.

Can Bedrock compare drawings from different sources?

Yes. Bedrock compares any two PDF drawing sets regardless of source. Drawings from different CAD systems, scanned documents, or mixed sources all work.

What if sheets don’t match between revisions?

Bedrock identifies unmatched sheets (new sheets in current, deleted sheets from prior) and reports them separately. You can review and manually match if needed.

Does Bedrock work with scanned drawings?

Yes, but accuracy is higher with native PDFs. Scanned drawings may have alignment challenges depending on scan quality.

Key Takeaways

  • Upload two drawing sets and get change analysis in minutes
  • Automatic sheet matching eliminates manual pairing
  • Auto alignment means no 3-point calibration
  • Changes are categorized by type with cost estimates
  • Works with all drawing disciplines (arch, struct, MEP, civil)
  • Outputs integrate with Bluebeam, Procore, and any PDF workflow

Last updated: 2026-02-04