Whilst building I noticed that some resources would be inside the roof, not on top of it like is has no collision.
Then I attempted this build:
My existing building
What I wanted
What I got
As you can see, the ladders are build through the roof. The building I tried to build on top the existing building was purely made out of slabs.
What!? But!! You are cheating!!! That’s not the good way to build things!! Who build a stone tower over the weak structure of a roof??? 
Well, See I have this hearthling. His name is Mark. Mark likes stone things on top of wooden things. And since I am a nice god, who am I to deny such a request. So, I granted him his wish. 
But do you know what this bug implies, no chimneys, no roof chapels, no…
Most of you won’t know this, but there was a time that creating a second floor was building a building on top of a building. Now, I can’t do that anymore 
While they no longer build “ladders to the gods” they do still build ladder/scaffolding through existing buildings.
