I printed out some of the QR codes using an inkjet printer for testing. I had a variety of results with the QR code readers I used on both my Windows 10 phone and Windows 10 tablet (so all apps/programmes were free windows based, not tested with IOS or Android Apps).
With iOS and Android there are a lot more QR reader apps that may perform far better than the windows ones.
Inkjet printed QR-codes tested for size, colour, contrast and richness of data. Simple URL codes easier to read by more QR reader apps
I found that simple QR codes that only had URL links were easy to read on all the apps, but with the more dense information the higher the resolution the reader needed to be. Colours also had an effect, generally light colours (low contrast) either were hard or were not read, whereas some with rich background colours were fine.
Size. I was initially thinking of putting QR codes on door jambs, generally timber doors are 40mm wide, so the simple URL QR codes fit into this nicely, whereas the richer data QR codes (room data files) would need to be broken down into smaller bite size pieces requiring maybe 3 QR codes instead of one to be able to be read easily and fit inside a door frame. Another potential location for the the QR code would be the meter box.
Windows QR code readers tested:
Lumina 550 Mobile phone- n Barcode reader and QR Scanner -Rapid scan
Windows PC using webcam – BeWebCam
Because it is optical based (rather than laser/1d based) it reads more data and is useful for mobile phones/tablets with good camera resolutions and auto-focus capabilities.
I think the barcodes can be printed on print paper with an ink jet printer, Best Quality will give the more reliable output.
I have noticed wear to barcodes ( I had some equipment from Hospital when I had a hip replacement & the barcodes wore out on some of the items ) so I think after you print to STICKY LABEL paper it would be better to put a sticky film over to protect the barcode . You will need to check film (leave in sun on windowsill (high UV in NZ) ) to see that the film does not become opaque over time as this will make it hard to read.
An easy way to reference back to complex website strings eg : https://pir2.tk/web/data/Panoramas/Views/laundry.html (would you want to try and type that on your mobile device on site? I wouldn’t)
Using colour on the Barcodes is a good idea, to either make them stand out (if they are in a concealed location) or to blend in (such as a timber door frame, use a tan background).