Question about the bulkheads

I'm pretty certain this question has been asked but I'm having trouble visualizing something. So I get the watertight bulkhead didn't go all the up. So does these bulkhead connect to the above deck and that connection wasn't watertight or did they just not reach the "roof" of their compartment? Like, if I was in the ship and looked up, would I see the wall meet the ceiling or was it just empty space. Thank you in advance. I keep hearing how they weren't secure at the top but tracking down a solid answer to this specific question has been difficult for me.