I finally found a proper way to get scrollviews working...

# View hierarchy:

*  UIView (Main view)
* UIScrollView (which I want of the same exact size of the Main view)
* UIView (Container View containing all the stuff to be displayed in the scroll view)

# Constraints:

## UIScrollView
* width equals to the one of the Main View
* center view on X axis horizontally (center X)
* 0 top an bottom margin with superview

##Containar View

* width equals to the one of the Main View - 0 leadin, trailing, top and bottom margin with superview (which is the Scroll View)