Kirigami project: lay down low-poly buildings to paper My project is to model a few low-poly buildings, then to loopcut each building by 4 or 5 on the X and Z axes in order to get each face (as a flatten sheet). Then get all those faces in front view/flat and lay them down to paper to be printed.

In fact my biggest doubt is about this last part, how to screen those faces one by one independently. And possibly with a "centimeter" metric system?

There may be something to do with the unwrapping tool most likely, but it's an option I still haven't ventured yet!

If you got my request, I simply need few tips or tricks you may have. I anyhow would do my best to obtain something right.
I'm not entirely sure I understood what you have in mind, but your description really made me think of the Export Paper Model add-on:

The add-on must be enabled (Edit > Preferences > Add-ons > Export Paper Model > ✔)



Create your mesh (or meshes) the way you'd normally do it. Blender 2.8x uses real-world measures by default: you can check in the properties menu (N) that the dimensions are the correct ones for your project (you can work on the model "cm" scale, or keep in mind a ratio, e.g. 1:125, and work at the real-world "m" scale, just make sure you then set the factor in the Paper Model add-on)



You can also use the Measure tool



Once you're happy with your mesh, you can use (N menu) > Paper > Export Paper Model. This will create a PDF with cut-and-fold paper model with the correct real world measures