Abstract: A rooftop ventilator includes a fan arranged for rotation about a generally vertical axis. The fan is on a rooftop curb through which air is drawn by the fan from the building interior. A housing extends over the fan and the fan terminates above and spaced from a curb to define a discharge opening for air drawn through the curb. A scroll arrangement is located above the curb and arranged around the periphery of the fan to receive air discharged by the fan and direct it toward the discharge opening. The scroll arrangement is made up of a plurality of scroll elements equally spaced around the periphery of the fan. Each of the scroll elements includes a first elongated element having one end generally adjacent the fan periphery and extending away from the fan periphery; a second elongated element, connected to the first elements to provide a generally continuous extension from the fan periphery. Each of the first and second scroll elements are linear.