You are looking at a grand plan.

Mostly to scale, the steps are exactly 240 x 190 x 900

floating blue rectangles are beds (I didn draw any legs on them)
also didnt draw any supporting legs/struts for the stairs or the floor
wall with a doorway on the top floor is 2400 with a 2100 doorway and looks like it will go beyond the cieling.. will have to do some more precise measurements.
http://wolispace.com/cow/img/wolis/stairs05.jpg