Abstract: A simplified drop celing room conversion is accomplished without, in any manner, disturbing the original ceiling of an office or room by providing integral, generally angle-shaped, longitudinally-extending structural members that are to be securely and fully mounted in an endwise-aligned relation on and about walls of the room at a desired lower ceiling height and, in such a manner as to fully and exclusively serve to support and carry a so-called drop ceiling. Each member has a horizontally-outwardly-extending upper shelf part for fully supporting and carrying cross-extending rail members that define open spaces therebetween with the sidewall-mounted supporting structural members, and which with the supporting members, are adapted to tilt-in receive dry wall ceiling panels in the spaces therebetween.