Is it ok to do this with faces?

Let’s say that I am modeling a house and one part has a bunch of details that are easily doable with loops, but would be more complicated to do with inset or whatever, is it ok if I:

  1. simply separate the face (in this case the entire side of the house)
  2. add loops and do whatever I wanted to do (random holes as an example)
  3. and then ctrl + j join the wall back and remove the 4 double vertices (marked red) ?

The remaining loops that end up with the vertices that aren’t connected to anything would be a problem if I wanted to subdivide or use some other modifiers, but if I want to leave it as it is, would this be ok?

what maters is the results, will the topolgy of the model hurt the end result ?
if yes !! thin fix it if no !! thin keep on
but from a personal experince i prefer to fex it, make sure the topolgy of the model is balnced and stable,

you never know what artifact you might face in the end because of this, and what you might need to fix lateron !!!

It only matters if you end up with artifacts. You could leave the end wall as a separate object.

I would be afraid that this would lead to light leaks especially on the interior or other render artifacts, and texturing/modelling workflow issues in the future.