subtrative meshes

hello ue4 developers.
im a bit new to ue4, and i have a suggestion that i think will improve the engine.
in my game i am working on making a city right now, but i have hard time making windows and doors, as my walls are destructable so i have to create a lot of them so there are holes.
my suggestions is to make an option is static meshes to be subtrative like world static objects are working.
it will help me for sure, and probably everyone else too.

You need to model your meshes correctly in your 3D program, doing a city with BSP is a very bad idea.