How High Should Sewer Vent Be Above Roof

Recommended minimums make sure the stack to protrude a minimum of 15 cm 6 inches from the roof.
How high should sewer vent be above roof. Vent pipes shall terminate not less than 6 inches above the roof measured from the highest point where the vent intersects the roof. I have a main vent and a sink vent and both are only 6 high above the roof. Where a roof is used for any purpose other than weather protection vents shall extend at least 7 feet above the roof and shall be properly supported. Some builders recommend a minimum of 30 cm 12 inches.
How high should the plumbing vents be above there roof. The regulations were changed from the days that you needed those 1m or so long pipes jutting from your roof. If the roof area is for people then it is 7 ft above the roofing surface. A vent terminal and depending if the roof is strictly for weather protection it terminates about 24 above the roof.
All open vent pipes that extend through a roof shall be terminated at least 6 inches 152 mm above the roof and not less than 2 inches 51 mm above the invert of the emergency overflow except that where a roof is to be used for any purpose other than weather protection the vent extensions shall be run at least 7 feet 2134 mm above the roof.