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Measure a house with an iPhone LiDAR scanner

The LiDAR sensor on an iPhone Pro or iPad Pro measures distance with light. With Apple's room scanning, it turns a slow walk around each room into walls, doors, windows and furniture at real size. Plotlay Scan (free) uses it to build a floor plan you can send straight into Plotlay.

Which devices

LiDAR is on the Pro iPhones from the iPhone 12 Pro onward and on recent iPad Pros. Other iPhones can still capture rooms by tapping their corners with the camera, which is slower but works without LiDAR.

How to scan well

  1. Turn the lights on. Tracking needs detail to lock on to. Dark rooms and blank walls are where it struggles.
  2. Walk slowly round each room, pointing at every wall, until the outline closes. Get into corners; open wardrobe doors only if you want them in the plan.
  3. Keep the phone up between rooms. The rooms line up because the phone keeps track of where it is as you walk. Put it face down on a bench and it loses its place. If that happens, go back to where you were, or start fresh in the new room and let Plotlay line the rooms up against your floor plan.
  4. Name rooms as you go. If you have a brochure plan, mark each room on it first; the app then walks you through them in order and names each scan for you.

How accurate is it

Typically within a few centimetres per metre on walls you scanned squarely. The weak points are long thin rooms, glass, mirrors, and rooms you only glimpsed. Check one long wall with a tape: Plotlay Scan lets you tap two points and type the real length, and rescales the whole scan to match.

From scan to plan

Rooms come in as separate shapes, so walls between them show as gaps of whatever width the scan saw. Square up rooms in Plotlay straightens them, lines up walls that should be one line and sets each wall to its real thickness. See wall thickness in Australian houses for the numbers.

More about Plotlay Scan →

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