As requested, interior height of my top closed is 69" inches approx. Opened up it is 100". No I ain't kidding, It's like being in a warehouse when opened! It must be noted though that when closed, you have to keep the bed folded out flat so you only have about 4' by 4' of opened space. I'm 6'2" and I can almost stand up straight comfortably in this space, even though the measurement is 3 inches less than my height, It is surprising how comfortably I can stand. With the bed flipped back and top open you have probably 8-9' of space front to back.