cupolas
dayton 2rb71 gravity roof vent26 in sq base
gravity ventilator fan size 16 in width 29 in depth 29 in overall height 12 3 4 in base width 26 in base length 26 in 829 572 cfm throat velocity 0.050 in sp gravity intake 973 671 cfm throat velocity 0.050 in sp gravity relief max intake cfm throat velocity 1812 1258 construction spun aluminum br b features b ul li base length in . 26 li li base width in . 26 li li depth in . 29 li li dimension a in . 26 li li dimension b in . 29 li li dimension c in . 11 li li dimension d in . 4 1 4 li li dimension e in . li li dimension f in . li li dimension g in . li li dimension h in . li li fan size in . 16 li li item gravity ventilator li li overall height in . 12 3 4 li li width in . 29 li li recommended 12 in . fixed curb item no. 2rb77 li li recommended 8 in . fixed curb item no. 4hx40 li li construction material spun aluminum li li cfm throat velocity 0.050 in . sp gravity intake 829 572 li li cfm throat velocity 0.050 in . sp gravity relief 973 671 li li cfm throat velocity 0.100 in . sp gravity intake 1173 809 li li cfm throat velocity 0.100 in . sp gravity relief 1375 949 li li cfm throat velocity 0.125 in . sp gravity intake 1311 904 li li cfm throat velocity 0.125 in . sp gravity relief 1538 1061 li li cfm throat velocity 0.200 in . sp gravity intake 1658 1144 li li cfm throat velocity 0.200 in . sp gravity relief 1945 1342 li li cfm throat velocity 0.250 in . sp gravity intake 1854 1279 li li cfm throat velocity 0.250 in . sp gravity relief 2175 1500 li li max . intake cfm throat velocity 1812 1258 li ul