The Basics of Venting in Plumbing in 4 Minutes

hey guys it's Jeff with Rising tide plumbing and today's episode we're going to talk about the basics of venting and Plumbing in four minutes and some change first of all the basics why do we need venting and plumbing so if we take this straw right here put my finger up and pull it out water's not going to come out of there until I give it to Mayor I like to tell people that in plumbing the movement of air is just as important as the movement of water proper venting in your plumbing system helps keep sewer gas out of the house by keeping all the p-traps full in all of your fixtures today we're going to talk about two types of venting one the drive vent where it's only air going through the vent part of the pipe and number two we're going to talk about the wet vent which the space in the pipe is shared by both air and water to properly vent the fixtures all these vents tie together and go through the roof or go into air admittance valves all right let's check out the dry vent first all right so every fixture needs access to air so in Drive vending this is how it works here's a toilet toilet flange you flush the toilet it goes out through the P-trap comes down it flushes and boom right here it gets to a dry vent coming off of the horizontal pipe and this is just like lifting the finger off the straw get this air and goes on Down the Line same thing with a shower or a tub and shower got the two inch P-trap water is going down hits the vent fingers off the straw and it goes all the way down as far as the lavatory goes water comes out of the P-trap down into the pipe and the dry vent starts right here it gets its air that it needs to go on down and on down and out of the house all right so that's dry venting to be honest with you it's a lot of work I don't typically do that unless I need to so thankfully we have wet venting so let's take a look at that all right so here we have the toilet the shower or tub and shower and the sink of what we call lavatory and plumbing so for a laboratory drain if it's by itself it only needs an inch and a half drain going to it in this situation and in wet venting this is a two inch line going to all the way to the trap on the lavatory what that does is oversizes the pipe going from here to here where you it allows for the water and the air to share the same space so the air can move on top of the water and allow for enough air to vent all these fixtures including the laboratory so what we have here is the wet vent actually starts right here where the water comes out of the P-trap and goes into this pipe the wet fin is from here to here because this is a vent that's doing two things that's allowing for the movement of water which is obviously a drain but it's also the venting on the top of the pipe is allowing for the movement of air which it allows for each of these fixtures to flush the way they should all right so with that example on this wet vent right here we have one fixture unit because we know that the lavatory is one we can talk about that another time this pipe has three fixture units on because it has the lavatory and then the tub and shower which is two so right here we have one fixture unit right here we have three fixture units on a two inch wet vent you can have up to four fixture units so that means we could even come off of here or even here and put another lavatory with a vent on it and that would still give us down here four fixture units on this last part of the pipe before it ties into the line with the toilet and we would still be okay all right so what I did in this little segment is I just took the exact same thing we just demonstrated and I added another tub shower and a lavatory so in a typical bathroom group like in a master bath now you have a master bath toilet you have two labs and then a tub and then maybe even a shower I've seen that a lot I've been doing that a lot lately so all that is is the exact same thing that we had here from the example uh previous and I added on this side another shower and another lavatory so this ties in separately this is vented uh the shower is vented through the lavatory and everything here is protected because when the toilet flushes by it protects this P-trap right here through the laboratory getting air from this and then like we said before all this is vented properly too so that's how it works on a bigger bathroom all right guys well thanks for watching hope it was helpful um hit like And subscribe and hit me up with some questions so we can keep walking this Plumbing journey together and the plumbing tip of the day not necessarily a tip but a recommendation but within an hour after watching this video go do something nice for somebody all right have a great day

Channel: Rising Tide Plumbing

Views: 292,828

Keywords: DIY, venting, plumbing, drainage, air, admittance, valve, wet vent, dry vent, fixture, unit, explained

Id: YWZOrZLnC9M

Length: 4min 23sec (263 seconds)

Published: Sun Dec 25 2022