Abstract: An improved exhaust fan housing, and exhaust fan assembly so characterized, is generally provided. The exhaust fan housing includes a first cylindrical or conical element, a second cylindrical element interior of the first cylindrical element, and a plurality of hollow vanes traversing an annular fluid passage chamber delimited thereby and uniting the first and second cylindrical elements. A central drive chamber, delimited by the second cylindrical element, is in fluid communication with ambient air exterior of the first cylindrical element via the hollow vanes. Each hollow vane is characterized by spaced apart wall segments which unitingly terminate so as to delimit a leading edge for each hollow vane, each of the spaced apart wall segments having a free end or a closed end delimiting first and second trailing edges for the hollow vanes.

Abstract: An improved exhaust fan housing, and exhaust fan assembly so characterized, is generally provided. The exhaust fan housing includes a first cylindrical or conical element, a second cylindrical element interior of the first cylindrical element, and a plurality of hollow vanes traversing an annular fluid passage chamber delimited thereby and uniting the first and second cylindrical elements. A central drive chamber, delimited by the second cylindrical element, is in fluid communication with ambient air exterior of the first cylindrical element via the hollow vanes. Each hollow vane is characterized by spaced apart wall segments which unitingly terminate so as to delimit a leading edge for each hollow vane, each of the spaced apart wall segments having a free end or a closed end delimiting first and second trailing edges for the hollow vanes.