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Can you scan a house with several floors?

Yes — but each room has to be scanned on its own, and it's you who tells the app which floor the room belongs to. Basement, ground floor, first floor and attic aren't something the phone can see for itself.

Why can't the phone tell which floor it's on by itself?

The LiDAR sensor measures distances in the room it's currently in — it has no idea whether there's one level below its feet or three. A room is scanned in its own local coordinate system, detached from the rest of the house, and the app's post-processing stitches rooms together based on where their walls physically meet. That stitching tells you how the rooms sit next to each other — not which floor they belong to, because that requires knowledge of the house, not just of the geometry.

How do you scan a house with several floors?

• Scan each room on its own, just as you would in a single-storey home — move from room to room, open the door, let the app capture ceiling, floor and walls.
• Mark the floor for each room, typically in a form right after the scan: basement, ground floor, first floor, and up to the fourth floor, depending on the size of the house.
• Repeat on the next floor. There's no shortcut that lets the app "know" automatically that you've now gone up a staircase.

The order doesn't matter — you can scan the first floor before the ground floor, if that suits where the family happens to be that day.

What goes wrong if you forget to set the floor?

By default, the room lands on whichever floor the app was last working in, or in an undefined group, depending on how the individual app handles it. In practice, that means a bedroom from the first floor can end up sitting visually on top of the living room in the floor plan, which ruins both the readability and any 3D model where the floors are stacked. This is therefore a step you should check before moving on — not something that fixes itself later.

What about the basement — does it count as a floor?

Yes, a basement is just another level, and should be marked as its own. That matters in two practical places: for the home's area, where a basement is often counted differently from habitable floors in the public building register, and for the 3D model, which needs to know that the basement sits below the ground floor, not next to it.

How does the app keep the floors visually apart?

A 2D floor plan typically shows one floor at a time, with a switcher at the top to move between them — much like an architect's set of drawings, where the basement plan, ground floor plan and first floor plan are each their own sheet. In a 3D model, the floors are stacked on top of each other with the correct ceiling height between them, so you can see the whole house as a building, or turn floors off one at a time to look into a single level.

Can you fix the floor afterwards, if you scanned it wrong?

In an app that stores the floor as an ordinary property of the room — not as something baked into the scan itself — moving a room to a different floor is typically a couple of taps. It doesn't change the geometry, only which group the room is displayed with.

Do two staircases in the house line up automatically?

No. If the house has multiple staircases, or an extension shifts the floors slightly relative to each other, you have to make sure yourself that the rooms on each floor line up geometrically — the app doesn't know that "staircase A" on the first floor leads to "hallway B" on the ground floor. It's the same task as when two separate scans of the same home need to be placed correctly relative to each other: a manual step, not something that resolves itself.

How many floors can you scan?

In practice there's no limit beyond however many levels an app offers as an option — basement plus four floors up is typically plenty for detached houses, terraced houses and most properties with an attic room. For a larger apartment block with many identical floor plans, the task becomes more a matter of patience than a technical limit: every room still has to be scanned and placed on its own.

A worked example: a house on three levels

A typical detached house with a converted attic might look like this: a basement with two rooms, a ground floor with five rooms, a first floor with four rooms under the sloped ceilings — eleven rooms across three floors in total. If the floor has to be set manually for each room, that's eleven choices, not one. Miss the marking on just one room — say, a bathroom in the basement scanned right after a bathroom on the first floor — and it can end up in the wrong group, and the result is a bathroom that visually sits in the middle of the living room in the floor plan. That's a mistake that's quick to fix if you notice it right away, but slower to track down if you only spot it in a finished report the next day.

What HouseSense does

In HouseSense, every room is tagged with a floor in the "Room scanned" sheet right after the scan — from basement to fourth floor. The floors are kept apart both in the floor plan, where you switch between them at the top, in the 3D model, where they're stacked in the correct order and height, and in reports and takeoffs. It requires LiDAR, because it's the room scan itself that the feature builds on — the floor is information you add afterwards, not something the app works out on its own.

How to plan a scan of a multi-story house

1. Finish one floor at a time. Scan every room on the basement level, check that they line up geometrically, before moving on to the ground floor.
2. Set the floor right away, while you still remember where you were — not in one big tidy-up afterwards, when the rooms all look alike in a long list.
3. Pay extra attention near stairwells and double-height spaces spanning two floors, which easily get scanned twice or not at all.
4. Look at the 3D model last, as the most reliable test of whether the floors actually sit correctly on top of each other.