[kustomwerker]

i know its not a car question, but i figured that car owners come from all walks of life, so here goes...i`m putting a bathroom on the 2nd floor of my house...i have a 4 inch cast stink pipe going thru the local area, and was wondering if i could tap it for the toilet drain, or if i have to run a seperate pipe...i can get all the rest figgered, but i dont want the existing crapper spewing dirty stuff upon the new one`s maiden flush...lmao...so there ya have it...

[nashcar]

You can cut out a section of the cast with a sawzall and replace it with a pvc wye and a short piece of pvc on each end. Then use a Fernco (rubber) fitting clamped to the cast to make the joint. If it's in a verticle section, you will have to buy a support for the cast above where you cut it. Without actually seeing it I can't say if this conforms to local code or not but should work okay. I'm not a plumber but I did stay at a Holiday Inn Express last night. ( Couldn't resist that one).

[JimM]

Yes, you can tap it. The "plumbing" part will not be a problem.

The problem you'll have to deal with is supporting the rest of that iron pipe, which does continue up all the way through the roof as a vent for the main floor toilet below.

Your best bet is gonna be to cut it off at the ht you need it to be, and go to PVC using a rubber hose clamp type coupling. This will all seal fine, but it WON'T support the 15 or more feet of iron pipe going the rest of the way up through the ceiling and roof. Best would be to pull it all above the first floor ceiling, and replace it all with PVC, all the way up through the roof.

Alternatively, you'll need to find a place to support it, probably at the next flange / joint going up, build something to grab it and take the weight before you make any cuts.

[pdq67]

I don't know if this is even possible, but Dad was a Master Plumber back when I was a small pup!!

I would cut the cast-iron pipe and install a c/i "Y" that is the right size on the split so that it will still support it's weight up top.

Then plumb into it w/ the plastic stuff and go.

You may get by w/ plastic BONDO joint caulk and oakum instead of real poured Lead and caulked oakum for the c/i joints but I may be off here!!

pdq67

[mjsmilford]

that pipe is heavy as JimM says so make sure to support it when and after you cut/snap it. also when "wet venting" as your about to do, make sure your new 2nd floor bathroom sink vent and drain are piped in higher than your toilet waste line. 3 feet is code here in ct.

[RSS]

Is there any other plumbing on the second floor? Just "tapping into" the existing 4" line isn't that easy if you want it done properly. If you are sure that the 4" vertical line is a vent, then you just can't add a bathroom or powder room and discharge all that waste in the vent. Its serving as a vent for the fixtures below, whatever they may be. What you should be connecting to that line is the vent for your new bathroom a minimum of 6" above the highest flood rim, which would more than likely be your new lavatory. Vertical wet venting is limited to one and two fixture unit fixtures (sinks, lavatories, tubs, showers) and only on the same floor level. You really need a drain line to tap into. Would it work? Probably. Definitely not the way I would do it. Not trying to discourage you, but as a plumber its just not the advise I would give.

[flat350]

RSS is correct , if that 4" line is a vent stack for the fixtures on the first floor you can't tie a waste line into it . If that is the only line that you have to tap into you would have to run another line along side of it and tie the second floor waste into the vent stack below the top vent bar for the first floor fixtures that it serves . Give me a better picture of what your trying to do .The support part is the easy thing to do and don't just use cheap rubber couplings use no-hub couplings they are rubber with a stainless support band . I'm a 30 year licensed plumber in Ill.

[kustomwerker]

thanx for the quick replies...heres the skinny...my bathroom and all other plumbing is on the first floor...the vent goes thru the 1st to 2nd and then thru the roof...it is exposed both up and downstairs...(meaning, not inside of a wall)i have a good sized walk in closet upstairs just outside of where the pipe is...the toilet would be about8 feet from the vert pipe and the sink would be about 4 feet...so, you cant put the sink drain and toilet drain together into 1 pipe and then into the vert pipe???or you can???i just dont know how else to do this without punching another pipe thru the floor, and having it exposed too...that isnt acceptable to me...what is the smallest drain pipe you can run for a toilet???i fas thinking of trying to push it down thru the exterior wall, but i`m pretty sure there will be fire blocks in there and soforth...(saying that, there may be issues with hiding the cold and hot water too...lmao...)

[68DaveV]

Tapping into the vent stack would make it a "wet vent" which is not allowed in most jursidictions. I would check with your local code enforcement.

[Rsmith1969]

I have seen Toilets and Basins tied in together on 3in. pipe but also i have see those people have issues with stoppages after a while , I wouldn't go any lower then 4in. pipe.
Also im not sure what a Homeowner can do inside their own house in Conn, But around here that Type of work (installing a powder room) Requires a Licensed Plumber and he must pull a Permit for it.

[RSS]

Originally Posted by kustomwerker

so, you cant put the sink drain and toilet drain together into 1 pipe and then into the vert pipe???or you can???i just dont know how else to do this without punching another pipe thru the floor, and having it exposed too...that isnt acceptable to me...what is the smallest drain pipe you can run for a toilet??? water

Kustomwerker,
Please re-read my post and flat350's. We're both qualified, licensed plumbers. Wet venting is a very common, acceptible practice in the plumbing trade, just NOT the way you are wanting to do it. You really need a new, independent line for this addition. The minimun size line for your toilet is 3" with a minimum 2" vent. Then you could add a branch for the other fixtures to serve your new lavatory (bathroom sink in laymans terms) and tub/shower if applicable. Or you can THEN wet vent to eliminate some piping below, depending on room dementions. You might consider the fact that you'll have to open up some walls to expose existing plumbing (if you want it done properly) and maybe add a chase or something similar to conceal the new plumbing. (This is NOT a 2 hour job). If you cut corners and stick to your original plan, you'll have to accept the consequences. Do it once, do it right, or reconsider doing it at all. We'll be glad to walk you through it. (Pics would be a great help). This is all very inexpensive to do if you are willing to do it yourself. Repairing walls and finding a source for the new 3" line is the hardest part of the job. The rest is a cake-walk.
So......... when do we start?

Rick

[flat350]

Kustomwerker Ditto to what RSS said and it sounds like the codes in Nv. are close to those here in Il.. There is no way that I would do what your trying to do , you can't be more concerned with how it looks than with how it will function , you will never be happy with the new baths operation the way your tring to do it .

[68DaveV]

I was being overly simplistic in stating wet venting is not allowed, but I believe both the IRC (3108.1) and UPC (908.1) limit it to fixtures on the same floor and then under very specific conditions. No? Anyway, you certainly don't want to waste drain your 2nd floor toilet down the vent stack.

BTW, if you have cast iron this may be a good time to evaluate it's remaining life. Typical life is 40-50 yrs.

[Corvettemaster]

I was going to put in my 2 cents until I seen the from Connecticut part. I escaped from there in the early 90's and from what I remember they'd just assume put you in jail for that sort of conduct. Florida does have its code issue with all the hurricanes but no one is going to try and rough you up for it. IF I sound bitter, I am! Six years as a city cop and a Licensed GC in CT was enough. Becareful what you do or the next knock at the door may be the plumbing overlords.....Does this count as my 2 cent?

[kustomwerker]

thanx a ton for all the replies guys...rick and steve, thanx for voicing your concerns...i`m really NOT looking to do anything wrong or illegal(except maybe the permit part...lol)i am heeding all the warnings...in fact, i talked to a friend (and reputible gc i may add) who has a lilcensed plumber on staff that i can use for his 25.00 hrly rate...sounds like it may just be easier to have him put in the drains, and have me clean up the mess...lmao...but tony said that the way i am looking to do this is acceptable as i explained it to him...the thing he pointed out that i didnt plan,but now realize the importance of is the sink vent...he said that without it, flushing the toilet will suck the water out of the pee trap, but venting the sink thru the roof would eliminate this, and i would be all set...i may just have his plumber come down for an hour and give me a visual inspection, and verbal discription of what needs to be done...i dont plan on doing this before christmas...you guys know how it is,right???lmao...i`m just getting things straight in my head as to what needs to be done...(and it should help me sell the house to boot)if i do anything sooner, i`ll definately shout out to all you guys...i appreciate all the help for sure...maybe i can get some pics up in the near future so you guys can see what i`m talking about anyway...to be honest, i dont even know yet if the joists run the way i need them to or not...