toilet vent length Home › Forums › Public Forums › Drainage & Sewerage › toilet vent length This topic has 0 replies, 1 voice, and was last updated 11 years, 9 months ago by Jean A. Gatto. Viewing 0 reply threads Author Posts 6 Mar 2013 at 7:42 am #280107 Jean A. Gatto I am installing a new toilet on the 1st floor but cant get a vent to the roof. Can I run the vent off the back of the elbow from the toilet flange and about 25 ft to the main vent stack? or can I use a wet vent system of the sink? Author Posts Viewing 0 reply threads You must be logged in to reply to this topic. Log In Username: Password: Keep me signed in Log In