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Re-scale a floor plan from one known measurement

Drag two crosshairs onto a span whose real length you know, type it, preview, and update — the entire plan re-scales to match.

3 minUpdated 2026-09-17

Traced and AI-imported plans sometimes arrive at the wrong size: the shape is right, but every dimension is off by the same factor, because the scale was set from a mis-read label or a guessed wall. You don't redraw. You re-scale the whole plan from one span you can measure.

Re-scale changes walls and structure on every floor by the same factor. Furniture keeps its place and its own real sizes, so a sofa stays a sofa.

Step by step

  1. 1

    Spot the problem

    The plan reads 16 feet across the front, but you know the real wall is 24. Any measurement you trust works — a wall length from the listing, a doorway you measured, the distance between two corners.

    The shape is right; the numbers are off by one factor.
  2. 2

    Open Re-scale

    Tap Edit Floor Plan Shape, then Re-scale. The instructions read Drag the two crosshairs onto two points you know the real distance between, then type that distance. Nothing changes until you tap Update floor plan. Two crosshairs land across the middle of the plan.

    Re-scale lives in Edit Floor Plan Shape.
  3. 3

    Put the crosshairs on a known span

    Drag each crosshair onto one end of the span you can measure — here the two front corners. On a phone or tablet a magnifier appears under your finger so you can land them precisely.

    Two points you can put a tape on.
  4. 4

    Type the real distance and preview

    Enter the true length in Real distance between the two points (your units). The dock shows New size: N% of current, and the plan previews the result — the original outline stays grey while the corrected one shows in green. Adjust until the preview looks right.

    Nothing changes until you confirm.
  5. 5

    Update Floor Plan

    Tap Update Floor Plan. Walls, openings, and structure re-scale on every floor; furniture keeps its position and its real dimensions. Measure again — the plan now agrees with the tape.

    Every floor re-scaled; furniture untouched.

Tips

Use the longest span you can

A 30-foot wall gives a more accurate factor than a 3-foot doorway; small measuring errors matter less.

Fix the scale before furnishing

It works either way, but a plan at the right size makes every furniture decision honest from the start.

Common mistakes

Resizing furniture to "fix" a small plan

The furniture was right; the plan was wrong. Re-scale the plan and the furniture stays true.

Using a measurement you didn't take

Listing dimensions are often rounded. Measure the span yourself if you can.

Frequently asked questions

Does Re-scale change my furniture?

No. Furniture keeps its place and its real sizes; only walls, openings, and structure re-scale.

Does it re-scale every floor?

Yes. The same factor is applied to all floors so they stay aligned.

When would I need this?

Any time a trace or AI import came in too big or too small — typically because the scale was set from an unreliable label. One known span corrects everything.

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