How do I slip-sheet a revised drawing and see what changed?

The paper workflow, digitized

Slip-sheeting is the oldest revision check in construction: lay the new sheet over the old and look for what moved. Digitally, the compare runs the same idea at pixel level — the two files go to the compare engine, which returns the bounding boxes where the sheets differ.

How a compare runs

• Open the old revision — the sheet with your existing markups stays exactly as it is.
• Run FOLDER:SLIPSHEET in the command line and pick the new PDF when prompted.
• The engine returns the changed regions; dashed revision boxes appear over those areas on the sheet you are reviewing.
• The new revision opens in the right pane of a synced split — pan or zoom one side and both move together.
• The report states the count of changed regions found.

Where it fits in a revision chain

Diff boxes tell you where to look; the version trail tells you what you approved. Save a named version snapshot before and after each revision exchange — the snapshot stores the PDF plus every annotation, measurement, and calibration — and the chain stays auditable: view any revision in its own tab, restore it, or mark it approved.

Honest limits

The compare sends both files to the backend for the diff — it is one of the operations that leaves the local workspace by design. It compares the current page pairing, so run it per sheet pair in a set. And the boxes mark regions that changed, not what the change means — a shifted wall and a shifted title block both box; the reviewer still reads the difference.

Doing it in PDFDepth

Ctrl+9 opens the command line; type FOLDER:SLIPSHEET with the old revision open. For a whole-set version record, Right panel → Collaborate Mode → Version History saves named snapshots along the way.