What Size Should Sewer Vent Pipe Be. Just as drain pipes remove water and waste from your home the plumbing vent pipe also known as a plumbing air vent removes gas and odors. A pipe increaser at the top makes no difference in the size of the vent.
Also 4 2 vents would do the job so you could have 2 on one bath 2 on another bath 2 on the kitchen 2 on the laundry. Connection between a vent pipe and a vent stack or stack vent shall be made at least 6 inches 152 mm above the flood level rim of the highest fixture served by the vent. Yours is apparently not sloped back toward the stack.
A pipe increaser at the top makes no difference in the size of the vent.
When installing your vents its highly recommended that you plan out your drain lines to minimize the risk of clogging. 10 ft 120-inches from nearest window measured horizontally. Then the vent pipe may be re-angled and a new cap may be put into place to keep debris from clogging it again. ABS pipe should be supported at least every 4 horizontally and at 10 intervals vertically.
