§890.TABLE K. Size and Length of Vents

Size of Soil or Waste Stack	Fixture Units Connected	Diameter of Vent Required (Inches)
		1¼	1½	2	2½	3	4	5	6	8
		Maximum Length of Vent (Feet)
1¼	2	30
1½	8	50	150
1½	10	30	100
2	12	30	75	200
2	20	26	50	150
2½	42		30	100	300
3	10		30	100	200	600
3	30			60	200	500
3	60			50	60	400
4	100			35	100	260	1,000
4	200			30	90	250	900
4	500			20	70	180	700
5	200				35	80	350	1,000
5	500				30	70	300	900
5	1,100				20	50	200	700
6	350				25	50	200	400	1,300
6	620				15	30	125	300	1,100
6	960					24	100	250	1,000
6	1,900					20	70	200	700
8	600						50	150	500	1,300
8	1,400						40	100	400	1,200
8	2,200						30	80	350	1,100
9	3,600						25	60	250	800
10	1,000							75	125	1,000
10	2,500							50	100	500
10	3,800							30	80	350
10	5,600							25	60	250

 

Agency Note:  Per Section 890.1580(e), no more than 20 percent of the maximum developed length may be installed in the horizontal position. Vent piping serving floor drains shall be installed in such a manner as to minimize horizontal vent distances.