I have a horizontal run of pipe that is about 3′ going through the I joists I need to 90 to the toilet which is 3′ away and 90 the other way to pick up a sink. I got a 3″ Y that reduces to 2″. Is there any problems with this configuration or code violation. I will 90 off the end of the coupler and 90 off the Y to the sink. I have a long sweep 90 for the toilet side if need instead of a regular 90.
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Where is your venting in all of this?
William the Geezer, the sequel to Billy the Kid - Shoe
I will vent it off the sink 2" . As it exits through the roof I will change to 3". Some people vent the toilet as well but I don't think it is necessary. Thanks. What is the code on clean outs?
I really don't know the plumbing code and understand very little of the drain and venting issues. I just asked about the venting as I you did not mention it and that can be an added complication..
William the Geezer, the sequel to Billy the Kid - Shoe
Some people vent the toilet as well but I don't think it is necessary.
I think that the inspector will think that venting the toilet is necessary. I also don't understand why you are reducing the pipe to 2", then upsizing it to 3" for the venting. If 2" is ok for drain and waste, it would ostensibly be OK for the vent also. If the toilet is wet-vented by the sink, then 3" should be proper. I didn't sketch out the design of rdesigns , but it seems about right.
Edited 10/14/2009 11:57 am ET by McMark
The 3" venting is required by code here. I am not a plumber by trade so I can not tell you why. With the other vents in the house they all exit the roof in 3". As for the toilets having an extra vent the existing toilets do not, they vent off the sink vent. It is only a half bath which app. 4' x 7' so the run from the sink to the toilet is a very short distance. I am not getting this inspected so that is why I asked for advice from some of the knowledgeable people on this site. I have a very good idea of what I am doing but with input from plumbers and there input would help. I will dry fit all and take a pic if I get a chance.
"The 3" venting is required by code here."
Then that means your plan fails. Your plan has only 2" venting, since that's the narrow point. You can't fix that by upping it to 3" as it passes through the roof.Mike HennessyPittsburgh, PAEverything fits, until you put glue on it.
Local amendments to the plumbing code are notoriously and frustratingly capricious.
Are you sure that a 3" vent is required for this combination of fixtures?
Or is it rather the case that your code requires that, somewhere in the system, there must be a 3" (or the equivalent sum of smaller vents) through the roof?
Are you on the UPC or some other code?
If it's the UPC or the IPC, what I posted earlier will meet either code.
The wild card is always the inspector. He may or may not read the code the same way as the rest of us. (Some are known to read the white parts instead of the black parts on the page.) So, to be safe, get him to bless your plan if he will. Unfortunately, some of them just aren't willing to talk to DIY'ers.
Here in Michigan, snow country, it's required a 3" threw the roof and the transition to 3" must be no less than 24" below the roof line. (I think)A 2" roof vent is what my inspector called a California code!!The larger 3" helps keep moist vented air from freezing at the end of the vent pipe and freezing shut the vent pipe. According to my inspector running a 2" vent then transition to a 3" , no less than 24" below the roof line was ok.
I hear ya. We have the same requirement in certain parts of the state here in Idaho--just N of here on the border of Yellowstone.
That's an example of a good amendment to the code.
It's not that bitterly cold in the BC country of the OP, but they may have adopted it to apply to the entire province, regardless of wintertime temperatures locally.
On a side note regarding vent capacities, it is amazing how small a vent really needs to be if it is sized on the two things that really matter: how many drainage fixture units and the length of the vent. (longer vents create more friction)
Edit: It just might be a lot colder than I thought in Central BC, maybe Silvertip will clear this up.
Edited 10/14/2009 4:52 pm ET by rdesigns
It may be due to cold I am not sure but I didn't make the rules and I only follow the code. I realize that switching from 2" to 3" seems not to make sense as Hennessay said but it is what they want. Temperature wise we may get down to an average temp betwwen -10 to -20 and usually a 2 week stretch in January that goes down to -30. Where I live we are considered desert area so the temp is usually not to bad. Thanks for your help
We're going to get 62°F tonight. Midwinter it has been known to reach all the way down to 38°F hereabouts. :)BruceT
I believe the fixture must be within 10' of the vent or you must run a new vent for that fixture.
What you need to do can be done according to code, and will give you no problems if you do it right.
Starting from the coupling: either before or after the 3" 90, place the 3 x 2 wye with the branch for the sink heading toward the sink;
roll the 2" branch of the wye up at 45 degree angle so that the sink drainage enters the top half of the wye;
continue the 3" line to connect to the toilet flange, using whatever bends are needed, but use the least number of bends and use 45's instead of 90's wherever you can.
The 2" branch will serve as a wet vent for the toilet if you continue it up past the tee for the sink as a dry vent. Keep the dry vent in the vertical, that is, no lower than 45 degrees from vertical.