CENTURY ATTIC STAIRWAY 8 ft. Model SA-89 Rough opening 25-1/2 x 54 x 89 ceiling height 300 lbs. rated Extruded aluminum construction Requires clearance of 70 swing clearance Landing space of 68 at maximum height 20 clearance between the springs Of all the aluminum stairs sold with a 25 rough opening 12 ft. height represent 37%. 10 ft. height is 14.5% and 8 height is 18.1%.