cupolas
dayton 2rb73 gravity roof vent34 in sq base
gravity ventilator fan size 24 in width 38 1 4 in depth 38 1 4 in overall height 12 3 4 in base width 34 in base length 34 in 1724 532 cfm throat velocity 0.050 in sp gravity intake 2101 648 cfm throat velocity 0.050 in sp gravity relief max intake cfm throat velocity 2970 926 construction spun aluminum br b features b ul li base length in . 34 li li base width in . 34 li li depth in . 38 1 4 li li dimension a in . 34 li li dimension b in . 38 1 4 li li dimension c in . 11 li li dimension d in . 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 . 24 li li item gravity ventilator li li overall height in . 12 3 4 li li width in . 38 1 4 li li recommended 12 in . fixed curb item no. 2rb80 li li recommended 8 in . fixed curb item no. 4hx42 li li construction material spun aluminum li li cfm throat velocity 0.050 in . sp gravity intake 1724 532 li li cfm throat velocity 0.050 in . sp gravity relief 2101 648 li li cfm throat velocity 0.100 in . sp gravity intake 2438 752 li li cfm throat velocity 0.100 in . sp gravity relief 2971 917 li li cfm throat velocity 0.125 in . sp gravity intake 2725 841 li li cfm throat velocity 0.125 in . sp gravity relief 3321 1025 li li cfm throat velocity 0.200 in . sp gravity intake 3447 1064 li li cfm throat velocity 0.200 in . sp gravity relief 4201 1297 li li cfm throat velocity 0.250 in . sp gravity intake 3854 1190 li li cfm throat velocity 0.250 in . sp gravity relief 4697 1450 li li max . intake cfm throat velocity 2970 926 li ul