Apex destructable with support stress

I am in the process of creating my very first game. The purpose of the game is a destructuon/demolition simulatotor, kinda like the “wrecking crew” gamemode of red faction guerrilla, where you get points for the amount of damage you can cause.

I have a problem though with my destruction system. If a tall building is half destroyed, and only held by a small amount of walls, i want it to collapse under the stress of the weight, if that makes sense.
does anyone have any good ideas on how this can be done?
i have tried constrainting all the walls, inner structures, etc. Together, but this usually dont hold up very well either on the physics side (building collapses way too easily) or preformance (too many physics at once). I also attemptet to simply use the functions in the destruction menu, but those funtions havent got any stress system, and i gues that its because the bodies are static until they get destroyed.
hope some of you guys can help. :slight_smile: