A damper having a housing includes a rotatable damper vane therein constructed to minimize the passage of air between the vane and the housing when the vane is in a closed position. The housing includes a pair of opposed walls having a channel or flute therein adjacent outer edges of the vane when the vane is in the closed position. The outer edges of the vane terminate in domed or arcuate shaped surfaces that generally correspond with the channel. The arcuate shaped surfaces are a distance apart that is greater than a distance between the opposed walls such that the arcuate shaped surfaces are received in the channels when the vane is in the closed position. The housing also includes a pair of opposed sidewalls having a ridge therein at a location that aligns with an edge of the vane when the vane is in the closed position.