A curb assembly for a heating, ventilation, and/or air conditioning (HVAC) system includes a frame configured to couple to a curb of a structure, a pedestal system configured to couple to a housing of the HVAC system and to the frame, such that the pedestal system extends from the housing to the frame, and an adjustable duct connector configured to fluidly couple an air flow passage of the housing with ductwork of the structure. The pedestal system is configured to enclose a space formed between the frame and the housing and the adjustable duct connector configured to be disposed within the space.