Abstract: A draft inducer blower for high efficiency furnaces, including a blower housing which facilitates maximum air flow efficiency through the blower housing while having an overall radial dimension which conforms to the industry standard arrangement of mounting holes on the walls of the furnaces. The blower housing generally includes a housing body and housing cover, the housing body including a plurality of mounting lugs spaced around the housing body through which bolts may be inserted to secure the blower housing to the mounting holes in the wall of a furnace. The housing cover and housing body each define portions of a volute which extends around the outer periphery of the blower housing from the cutoff region to the exhaust transition of the blower housing. The volute includes a cross-sectional area which substantially continuously increases in the axial direction of the blower housing from the cutoff region to the exhaust transition.