The Epicore dovetail ribs provide a simple, economical, and permanent means for hanging ceilings, piping, ducts, and other mechanical and utility components. Hangers can be purchased, installed, and reused as they are required; consequently advanced planning is unnecessary except to determine loading requirements. Since there is never a need to drill into a finished floor slab or roof, changes after occupancy can be handled with minimum disarray, noise and interruption of normal functions.