Pugsley: Are they dead?
Wednesday: Does it matter?
Gomez Addams: [admiring Morticia, who is sleeping.] Look at her. I would die for her. I would kill for her. Either way, what bliss!
Gomez: Have no fear. The courts will decide. They say a man who represents himself has a fool for a client. Well, with God as my witness, I am that fool.
Answer: No doubt the Addams house had one of many secret, confusing passageways to get to the higher floors (and other parts of the house) from the vault that the viewer obviously is not privy to.
Scott215