a multi - section roll - up curtain is raised and lowered by plural support / rotational drive mechanisms disposed in a spaced manner along the length of the curtain . each drive mechanism is symmetrically loaded with a curtain section attached to opposed sides of each drive mechanism . each curtain section includes plural vertically spaced curtains which are simultaneously rolled - up and unrolled . each drive mechanism includes plural vertically spaced drive motors each connected to first and second curtain - bearing roll - up tubes disposed on opposite sides of a drive motor . a generally vertical guide member is coupled to each drive motor by a respective carriage assembly allowing the drive motors to travel up in rolling up the curtains and down in unrolling the curtains . this arrangement accommodates the large torques encountered in operating long curtain sections permitting multi - section curtains 600 ′ and longer in length to be reliably and safely operated without using large , powerful motors .