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akajimster
Dec 14, 2009, 03:38 PM
I am adding plumbing to a room above our garage and laundry room to be able to rent out as a one room studio. The main lines & branches have already been run by a handyman/plumber friend of a friend and I've got a few concerns about the layout and whether I'll have problems with the venting or who knows what else. I know I definitely need to add a cleanout; don't know where the best spot for that would be(perhaps add another wye just before the closet bend?). Forget about asking the inspector to have it inspected; I tried the legal route first(getting a permit); every time I went down to the city to double check requirements, etc. the price went up as did the requirements, which had nothing to do with the plumbing. I've attempted a diagram and looking for feedback and suggestions for improvement. I posted in another forum and have gotten a little feedback, but nothing to confirm this is good to go. A couple of notes on the diagram, the vents from the kitchen sink and lav sink will go all the way up into the attic, will be tied together and go out the roof. All items in red boxes are vertical, the rest is pretty much horizontal as if looking at it from above. The shower and toilet will be wet vented from the lav(if this is done right). The city goes by the UPC, if that's any help(even though I'm not getting permits, I'd still like it to meet code, just in case;)). Thanks in advance.

massplumber2008
Dec 15, 2009, 05:47 AM
Hi Aka Jimster...

The plumbing is close, but to my knowledge you can't have the kitchen sink connecting into the WET VENT for the toilet. Here, the lavatory vent, which should be 2" here, acts as a wet vent for the shower and the toilet. You cannot have the kitchen sink connect into this wet vent in any way.

In order to make this right in my area you would need to cut in another 3"x3"x2" wye behind the existing 3"x3"x3" wye... about a foot back minimum... and then connect that onto the kitchen sink drain line. Of course, you would need to cap the kitchen drain off the existing line as it is now.

Finally, all those 2" 90s should be 2" long sweep elbows... are they?

Let me know what you think...

MARK

akajimster
Dec 15, 2009, 06:05 PM
Mark-

Thanks for the modified drawing. Yes, after the main 3" sewer line, everything is 2". The 90s you see are long bend, with the exception of the vent lines in the attic.

What you said about the lav drain, I also heard on another board - not what I wanted to hear:( No big though, seems like you gave me a simple solution! It may actually help a bit - instead of capping off the kitchen drain line, could that be used for a cleanout? Instead of a 45 wye off the 3" line going to the sink, would it be ok to use a long bend 1/8 wye; that would give me a straighter run over to the lav sink?

On another board, they said the toilet also needs to be vented, which I agree with, but, doesn't what I have suffice as a wet vent for the toilet and shower? If so, I shouldn't need a seperate vent for the toilet and shower, right? If I do, I don't think I would be able to add a 3rd wye fitting in front of the closet bend because of a wall right next to where you have me putting in the 2nd wye to the kitchen sink. Another alternative, if I do need a vent, can I tap into the vertical pipe between the closet bend and where the toilet will go(I've got 10" joists there, so there should be room)? If so, what do I use, sani T, long bend wye, or??

Finally, where the horizontal sink vent in the attic meets the lav vent, do I use a regular T or a sani T? If sanT, does the bend go up or down?

Thanks

massplumber2008
Dec 15, 2009, 07:07 PM
In most places in the good ol' USA wet venting is allowed (as long as you remove the kitchen sink) and you will not need another vent for the toilet or the shower... :) However, you should double check to see if wet venting is allowed in your area... if not then you may decide to install the individual vent(s). Basically, if wet venting isn't allowed then you not only need to add a 2" vent for the toilet, but you also need to add an 1.5" vent for the shower, too... *OUCH*!

If wet venting is allowed use the "long bend 1/8 wye" (as you called it... we call it a combination wye 1/8th fitting) to pick up the kitchen sink. The 2" line doesn't have to be capped off and could be used as a cleanout if it is accessible in some way... ;)

Back to you...

MARK

akajimster
Dec 15, 2009, 09:55 PM
In most places in the good ol' USA wet venting is allowed (as long as you remove the kitchen sink) and you will not need another vent for the toilet or the shower...:) However, you should double check to see if wet venting is allowed in your area

That's good news! The wonderful:p building and safety dept. in my city actually provides some useful diagrams and examples on their website, but, here's one contradiction with their general notes on one of their diagrams: It says: "Every plumbing fixture shall have a separate trap and each trap shall be vented". Under vent piping notes it says: "Never use the vent from one fixture as the drain for another fixtre unless the system meets the requirements in the U.P.C. for vertical wet venting and combination waste and vent systems. Sect. 908 & 910 U.P.C." :eek: Real consistent, huh?

Anyway, if you could answer last question from my previous post - where the horizontal sink vent in the attic meets the vertical lav vent, do I use a regular T or a sani T? If sanT, does the bend go up or down? Also, regarding 90s, can I use a regular 90(versus long bend 90) when transitioning from horizontal to vertical drain or is it good practice to always use long bends on the drains?

Thanks again Mark, you've been a big help.

Milo Dolezal
Dec 15, 2009, 10:51 PM
Hello Akajimster, you are in Ventura County, Ca, correct ? I am based in So.California and I work under UPC every day. We also do lots of work in Ventura County. Presently, we are doing one project in Moorpark and other one in Simi Valley...

In regards to your drawing: Every plumbing fixture has to be vented to pass required inspection. No way around it. Inspectors are very fuzzy about it here. Even if your project is not inspected, it makes for good practice to do it the right way so you don't have problems when selling your house.

As other Experts already advised you, toilet must have 2" vent, shower and sinks 1 1/2" vents or larger. All vents can be connected above flood level ( about 48" above the floor ) into single 2" vent and than run this vent through the roof.

Toilet drain should be 3" or 4". ( Use 3". It is lot easier to work within the ceiling joists ). Shower drain and Kitchen drain should be 2". Lavatory drain 1 1/2". You can use ABS to rough it in only if the ceiling below inside the garage will be finished with drywall to meet Fire Code requirements. Maintain 1/4" slope for 3" pipe or 1/8" slope for 4" pipe.

If you have to run pipes through joist - Drill Holes. Do not notch them with sawzall. Drilling will maintain structural integrity of joists. You can buy Milwaukee or Lennox self-feed drill bits in Home Depot that are made for ABS pipe. Be careful here with sizing of the bits.It may be confusing. For example, 2" ABS pipe takes 2 9/16" drill bit etc..

I will redraw your lay out showing how it should be done correctly. Each red dot is vent or drain/vent combo. Install clean out on each vent about 10" above the floor. Clean out should match size of the pipe it services. For toilet, bring 3" line above the floor, install Clean Out and then you can reduce to 2" for vent.

Good luck with your project. Let me know if you need any other help.

Milo / Los Angeles County

massplumber2008
Dec 16, 2009, 05:17 AM
Ahhh... I didn't see the CALIFORNIA designation in your post Jimster... ;) As Milo confirms then, I am afraid you are in the minority in the country and you will need to individually vent each fixture... *OUCH*!

Milo, can you help me and the Jimster understand what is meant by the statement he posted, " "Never use the vent from one fixture as the drain for another fixtre unless the system meets the requirements in the U.P.C. for vertical wet venting and combination waste and vent systems. Sect. 908 & 910 U.P.C."

It appears that they finally allow some form of wet venting in your area... but when is it allowed?

Thanks for jumpin' in Milo!

MARK

akajimster
Dec 16, 2009, 06:08 PM
Ahhh... I didn't see the CALIFORNIA designation in your post Jimster... As Milo confirms then, I am afraid you are in the minority in the country and you will need to individually vent each fixture... *OUCH*!
Yeah, ouch is the right word - along with a few other choice words!;) I guess I "interpreted" what I wanted it to be - that wet venting is allowed in this situation. But after finding the Calif Plumbing Code online and taking a closer look, the one thing that stood out was that wet venting is allowed where it is "structurally impractical to provide venting in the convential manner" and plans/drawings presented the city and approval obtained before installation. Approval before installation is one thing, after the fact - when the city's got me by the short and curly's because of an unpermitted use - is whole different matter! I'd rather have it right than wrong I guess.

Milo - yes, I live in Santa Paula. Not sure if you've ever done work here, but, the inspectors tend to have Napoleon complexes with huge chips on their shoulders. I've got a client with 3 rental properties on the same lot where she did some repairs/improvements on 1 of the units and when the city came to inspect they made her install new windows on all 3, redo plumbing, gas lines, subfloors and a host of other BS that just blew me away. That's where a $10k job turned into over $100k.

I'd agree with you, "makes good practice". So, I guess it's back to the drawing board! I'm going to take a look at what you suggested and see if it will map out. My biggest challenge is there is only 17" between the wall and where the toilet bend connects to the 3" main - only enough to fit two wyes there. The plumbing layout in the diagram is in a closet in the laundry room, so, space is a bit limited. I may flip-flop the locations of the shower and toilet if I can't figure anything else out. Good tip on drilling through the joists instead of notching. Does the cleanout on the toilet really need to be 3"? Can that go off the stack above the closet bend? Where the horizontal sink vent in the attic meets the lav vent, do I use a regular T or a sani T? If sanT, does the bend go up or down?

Thanks again for the drawing, both of you have been a big help! I will repost after I modify things to get your feedback, if you don't mind.

Milo Dolezal
Dec 17, 2009, 08:48 AM
akajimster: No, we don't go that "far" north on every day bases, but we worked as north as Mendocino and Napa Valley on larger projects...

Even if you are only 17" from the wall you can rough it in relatively easily. Do this: run your toilet line to the wall, make transition from Horizontal to Vertilac using 3"x3"x2" heel 90 (see photo), continue downward with about 36" piece of 3" vertical pipe, then install 3"x2" Y pointing upward and bring this 2" line back to the ceiling. You will use this pipe to connect your small fixtures to it. Than continue down to connect with existing 3" drain and upwards with all the vents.

Regarding Clean Outs: You are not required to have clean outs on every fixture on 2nd story. So you could omit the toilet clean out completely. If cloggage happens, you would clean the line by removing toilet and inserting snake through toilet opening. Skip the shower clean out. I would definitively install clean out on sinks. However, you will have to install 3" clean out on 1st story, before this pipe enters slab.

Let me know if you understand the concept of it. If not, I will draw you new sketch.

Milo

akajimster
Dec 17, 2009, 08:34 PM
Milo- I couldn't really vision how what you described would work in the situation I have. Anyway, after looking at all your valued feedback, I did decide to swap the toilet and shower location. I attached a new layout that seems a lot simpler than before. I think I've got a descent handle on what to do for the most part, but, for the shower vent, where would the best place be to connect the vent: between the p-trap and shower drain and drill hole through one joist to run to the nearest wall?

I will try and post pics after I get everything together - before I glue it up to see if it's good to go.

Thanks a bunch to you and Mark - you guys are great!

Milo Dolezal
Dec 18, 2009, 08:01 PM
Ok, that is no problem... you will install the shower Y connection in front of the sink Y - both connected to 3" pipe from the toilet via two 3"x2" Y's. See the sketch for better visual. Everything else remains the same... That rolling 45 for toilet vent is OK.

Let us know how you did... Good Luck... Milo