He may be refering to a vent that is layed flat, or nearly flat for a toilet vent.
A vent pulled off of a vertical santee isn't going to go bad.
Or a combo on it's back going vertical.
Breaking my promise, I am posting another thread.
I just got my plumbing rough inspected, and it passed. However, I used individual, dry vents for the WC, Tub and Shower. The inspector passed my work, but that it was actually 'old code'. He said 'new code' prefers you to wet vent a bathroom group. He says dry vents tend to get clogged, and once clogged, there's not any way to fluch out the clog, and bye bye vent. Not wanting to argue with him, since he is the expert and more importantly the inspector, I thanked him for both his signoff and his advice.
Now to my question... I'm under the IPC in GA. I have scoured the Sanitary Sewage and Vents chapters 2009 IPC (as well as the 2006 IRC and my state's supplements) and I do not read anything that expeicitly states wet venting is preferred over dry venting for a bathroom group. Am I missing something? Is this something that plumbers just come to know through years of training and experience that we novice homeowners simply will just not get by reading a code book?
He must have been a plumber who learned the trade under the new rules, otherwise he would NEVER have made a statement like that. Did he happen to mention WHAT would plug a vent that was not accessible? I am surprised he didn't tell you that AAVs were even better because they did not have a pipe that could get plugged.
I'll go one better. He's an idiot. Neither method is "better" than the other. It's all situational. I wet vent whenever possible because it saves time and money, period.
He was an older gentlemen (probably late 50's to early 60's), and I did not ask how long he'd been in the trade.
He did not say how the vent could become clogged, only that he'd seen many times where a clogged dry vent could not be cleared.
I asked if I should install some cleanouts and he said 'No, what you've got will probably work fine.'
When I was an apprentice, I also had an older gentleman working with me. he was the plumbing inspector for a neighboring town. After I fired him for poor workmanship, the apprentice at the shop where he went to work used to tell me that if you got a few beers into him and then asked him about apprentices, he would go on for a long time about that "apprentice who thinks he knows everything, and I have been a plumber for over 25 years". So time in the business is not an indicator of ability. As for "many vents that have plugged up", it could be hyperbole and it was really one, and that one was told to him by the guy who knows the guy who knows the guy it happened to. If something can fall down the vent to plug it, unless it is a piece of pipe or lumber, then the thing to unplug it can come down the same way. If that cannot happen, then nothing is going to plug the vent unless it is improperly installed so drain material can get into it during a backup, and if that could happen the pipe should not be that way, but is supposed to have a cleanout.
Squirrels, mice, rats, leaves, pine needles, ice, and all sorts of other things can clog a vent. Doesn't matter if it is wet vented or not, it can block the vent line. Sounds like BS to me.
Important note - I'm not a pro
Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013