Guide
Vector vs scanned plans: why it matters for AI takeoff
In short
A vector PDF stores the drawing as lines and shapes, so software can read exact lengths from it. A scanned plan is only a picture, so the software has to detect walls and items in the image first. Most plan sets today are vector; older or re-issued sets are often scans.
On this page
How to tell which you have
- Zoom in hard. Vector lines stay sharp at any zoom; a scan turns blurry or blocky.
- Try to select text. On a vector sheet you can usually highlight the room names and notes.
- Look for stamps and skew. A slightly crooked sheet with handwriting or a wet stamp is almost always a scan.
Why it changes the takeoff
On a vector sheet the wall is already there as geometry, so its length is a reading, not an estimate. On a scan, a detector has to decide which dark pixels are walls, which is where fragments and gaps creep in. Either way, the scale has to be right, and the tool should tell you how it measured each sheet.
How Field24 handles both
Field24 reads exact lengths from the vector layer where there is one and runs a wall detector on scanned sheets, so one plan set can mix both. Every row is marked on the drawing either way.
Common questions
Can AI take off a scanned plan?
Yes, with a detector that finds walls and items in the image. Expect to spot-check scans more closely than vector sheets.
Should I ask the architect for vector PDFs?
If you only have a scan of a set that was drawn in CAD, asking for the original PDF export is worth it: lengths come straight from the geometry.
Keep reading
Last reviewed November 9, 2026. Cite as: AI for Construction, “Vector vs scanned plans: why it matters for AI takeoff,” https://ai-4-construction.com/guides/vector-vs-scanned-plans/