Abstract: A scaffold support assembly comprises a support subassembly, a brace subassembly and a position adjustment subassembly. The support subassembly includes a longitudinal base member and a stabilizer member attached in transverse relation to and extending in opposite directions laterally from the longitudinal base member. Both the base and stabilizer members are adapted to lie flat on the roof. The brace subassembly includes vertical and horizontal members and an elongated flexible member. The vertical and horizontal members are connected at adjacent ends to the base member and pivotally movable relative thereto. The elongated flexible member extends between and interconnects remote ends of the vertical and horizontal members such that the elongated flexible member and vertical and horizontal members are arranged in a right trianglar-shaped configuration. The position adjustment subassembly includes a brace, a bracket, and a fastening element. The brace is rigidly attached to the base member.