RoomScan Pro

Today we went to a seminar about remodeling with Stearns design-build to get some ideas about some remodeling plans. In talking about things, I decided that we really need a better diagram of our house layout. It doesn’t have to be super precise, but I want a starting point to sketch from. I thought there might be an app for doing measurements and it turns out there are a couple

  • Magicplan uses the camera. It sounds interesting but this review makes me leery of the “subscription” part. It also seemed to me that there could be issues with obstructions.
  • RoomScan from locometric works using the GPS, gyroscope, the camera and who knows what else (accelerometer?) to take measurements based on tapping your phone against the walls

As with anything that involves extrapolation from the phone to do a complex task, getting dimensions right with RoomScan isn’t quite as easy as it looks in their demo video. But it’s still pretty cool, and their support people are very fast to answer questions via twitter to @locometric.

Testing – technique matters


Figure 1

In my first attempt to create a floor plan (Figure 1), the numbers were off. The app did warn me about the measurements possibly being off. RoomScan does provide a way to adjust the lengths of walls manually, but some of these were way off. Could this be due to the extended wifi network? Are the numbers reproducible? Was I doing it wrong?

RoomRoomScan L (EW)RoomScan W (NS)L W
Master BR11.511.513.7514
Master Bath10.5 in 2 segments119'1"7.5
Main Hall263303.5

I decided to do some experiments. First, I repeated the hallway a couple of times. After two failures, I switched the phone to Airplane mode. I also changed the tapping pattern (see below). RoomScan worked fine in Airplane mode, showing that the wifi and cellular signals aren’t being used. Once I got it right, I switched Airplane mode off, and did more replicate scans. Figure 2 shows the last test.

Test 1Failed
Test 2Failed
Test 3313.5
missed a door
Test 430.5
21 to BR door
Test 530.5
21 to BR door
Figure 2

Figure 2

So, I think that the problem with dimensions is that I wasn’t moving fast enough for the accelerometer to work optimally. RoomScan warns you about this. There’s a voice message that says things like “I work best if you move quickly but smoothly” or “Keep the time between taps short” (not transcribing these exactly”. It appears that RoomScan uses the lack of light from the camera to determine that you’ve tapped a wall.

It also took me a couple of tries to figure out what it wants to close the polygon. It’s not enough to tap on the same wall past the starting tap. For these, I started on the lower wall to the left of the BR door and went counterclockwise. At the opening I did wall tap, opening tap, opening tap on the opposite wall, wall tap before heading down the long part of the hallway. Coming back, I had to go through through that whole sequence a second time to close the loop.

Adding rooms

Next, I deleted all the hallway tests but the last one, which I used as the hall. Unfortunately RoomScan wouldn’t let me rename it. I got the Pro version because it wasn’t very expensive ($4.99) and it allows you to add rooms through doors. You open a previously scanned room and touch a door or opening as a starting point. RoomScan brings up a control wheel with different options. These include the ability to change the kind doors to openings and vice versa, and flip which way the doors open and which side the hinges are on. Tapping a wall gives a similar control wheel that allows you to add doors that you didn’t scan in earlier.

RoomScan control wheel

Figure 3. Control wheels for editing adding rooms

Selecting add room through door/opening prompts you to name a new room and then click Add. Depending on what kind of connection you start at, it tells you to start in the middle of a closed door, or on one side of an opening.

In my initial tests, I didn’t get the opening at the end of our hallway right, so I used the add door function to create an opening.  Starting with an opening you’ve added via the edit function doesn’t work right. I’ve emailed service@locometric with screenshots, and they replied very quickly (on a Saturday no less) promising a bug fix in the near future regarding the openings behavior. But the add room through opening works fine if you create the opening in the original scan.

Figure 4

Figure 4. tapping to get an opening.

Figure 4 is an image RoomScan support sent me to show how to do it right. Essentially, you double-tap each side the opening: once to set a wall point and the second time to set an opening point. The order goes wall-opening-opening-wall.

Once my scanning technique got better, I was able to add several rooms off the Test 5 hallway. Figure 5 is what I have so far. RoomScan automatically places each room based on the opening or door you previously started with. You can adjust this by tapping a room in the overall overview and dragging it to a new position. My three problems with this are

  • It isn’t precise enough. It would be really nice to be able to just nudge a room by a little bit. You can see the nudge problems in how the rooms line up.
  • Roomscan’s floor plan view tries to merge openings and doors into nearby spaces a little too aggressively.
  • It tends to crash in this mode

I want the connection with the opening I started with, and there are times when the openings do need to be connected. For example, our dining room has openings into both the living room that should be connected when I scanned the Dining Room starting from the Kitchen with the Living Room already on the floor plan. This connection is presumably made by recognizing that two openings from adjacent rooms are overlapping. But the overview also tried to fuse two kitchen closets into the back of the Master Bathroom. It didn’t create new doors in the bathroom, fortunately, but it was disturbing to watch the doors connect like cytoplasmic bridges between cells as I tried to move the Kitchen into place.

I also had to do some fudging on where I think the boundaries of the rooms are. The way our flooring is set up, I think of the boundary between the living room and Kitchen as being diagonal. I don’t think RoomScan likes diagonals. I’d be interested to see how it works on floor plans with different angles between the rooms.


Figure 6. The partial floor plan


RoomScan Pro is not going to replace a professional draftsman spending days and $$ to generate new architectural plans for your house. It’s not going to give you elevations. But at $4.99 it’s a lot better than what we were doing for early stage brainstorming – running around with a too short tape measure and sketching on paper. That said, what I think I’ll end up doing is:

  • Tweak the measurements in the app and export the image
  • Import the image into Notability or a drawing app and sketch on top of it on my iPad.

That’s partly because I’m not sure how to export RoomScan output as objects to a drawing program where they can be edited on my laptop (It’s not clear that any of the home/interior design apps handle that well either; what are the file format standards, anyway). It’s also because even if I could export editable files, I don’t currently have anything to import and edit them.