Non deeded terrace

I can not speak to this building, but lots of condos have all the "private" outdoor spaces as "Limited Common Elements" which can actually be an advantage because when the inevitable leak happens it's the building's responsibility.

My review of various buildings where I’ve gotten into the governing docs is in line with 30yrs. The downside of the Limited Common Element in my limited experience is that even though it is the building’s resonsibility to repair any Limited Common Element, getting the building to actually do it is difficult unless another unit is affected and forces the issue. I reviewed this for a friend who wanted to repair the balcony outside her unit at her own expense but was shut down by the managing agent because the balcony was technically the building’s responsibility, and they said she did not have the right to improve the limited common element. When looking at the building from the street it looked like all the balconies might suffer from the defect hers was suffering from (water pooling under the tile such that many were loose and the balconies all had what looked like an inch of mildew/mold on the side that was visible from the street). She said there had been talk among other owners and that they had been similarly shut down but went ahead and did it anyway. I directed her to an attorney who is expert in such matters. This must be a fairly common fact pattern.

And if it's a limited common element, at what point can the building 'take it back' for some other use? (Thinking here of the UES buildng where the board (co-op, I think) put two large AC units on the setback adjacent to an apartment. Lawsuits ensued.