The collapse left at least three workers stuck in two different cherry pickers elevated off the ground but stuck at odd angles. Firefighters were unable to reach them from the ground and had to hoist them out of the equipment by chopper.
Crews responded to the scene on S. Glendale Avenue near Chevy Chase Drive just before 11 a.m.
Exactly what caused the construction material to collapse is not known.
No serious injuries were reported. The construction site is for a future movie studio.