How to model window into wall I have an architectural scene that I imported from 3ds max, however there is no windows in walls. Problem is, the scene doesn't have strict scale (I don't know measurements of the holes). 

How this problem should be approached, because there is quite a few windows in my scene.
Just scale things properly and use Archimesh's windows. (Blender 2.78c comes with latter and you just need to enable it in User Preferences -> Add-ons.)