I have a solution, but it requires coping the current wall. You can create the first wall with specifying an offset for the bottom of the inner wall and choose the material for it. and the copy and past the new wall and place it exactly in the same position, and this time remove the bottom offset and instead specify an offset for the top of the wall. (keep in mind to calculate the offsets accordingly so the sum of both corresponds to the height of the wall.
You can delete the outer side of the copy-pasted wall as well. Now you have the inner side with two materials and the positioning of the windows and doors are intact and clean.
Hope it helps 🙂
'P.S. for the offset of the top of the wall you need to specify the value in negatives. otherwise it will add to the height of the wall if you specify in positive value 😄
Cheers,
Arash
