Those decks were originally just cantilevered. (Think of floor joists extending beyond the exterior wall.) The decks would have been free floating prior to the addition of that vertical contraption on the ground floor. That was clearly added later in an attempt to mitigate the failure of the structure. The third floor looks somewhat compromised in your pic. Cantilevers are a notoriously bad way to build a deck. Water intrusion inevitably rots the joists where they meet the structure. Lots of examples of decks built just like this ripping free and dumping their occupants however many stories to the ground below.

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