Basement Bathroom Rough-in layout help please... :)

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by Squints2See, Sep 27, 2012.

  1. Squints2See

    Squints2See New Member

    Messages:
    33
    Location:
    West by God Virginia
    Hello all,

    I am helping a friend rough in the plumbing for a basement bathroom. There was an existing bathroom there but he had to terror out the entire concrete floor and start over due to broken pipes underneath the concrete.

    I have poorly drawn a mockup of what I am looking to do. I have researched things as best as I can and have found out that in my neck of the woods the 2009 IPC is what is used. However, there are no inspections done where my friend lives, so although I do want the plumbing to perform properly, I will not have to contend with a picky inspector.

    Based on my research (and I apologize in advance if I get some of this wrong) the IPC does allow wet venting with one vent for two bathroom groups as long as it is on the same floor, which this is. And I seem to recall reading that based on a 3" drainline, the furthest fixture can be up to 12' away from the vent. (Im not sure I am understanding that right though; Table 906.1 of the IPC)

    So here are my questions:

    1. Would it be better to have the toilet directly inline with the drain, (using a 3"x3"x2" tee-wye) or have it branching off of the main drain as shown in the optional placement in the drawing?)
    2. Should I go with my original plan of having two vents coming together (as shown in purple), or can i use one 2" vent (as shown in the dashed green) as long as it is placed close enough that it is within 12' of the farthest fixture?
    3. Is it better to have the vent upstream from the toilet (as indicated in the purple option), or downstream from the toilet?(as indicated with the dashed green option)
    4. Could I use 1 1/2" line for the vents instead of 2" if I do the vent placement shown in purple?

    The main drainline will be 3", and will tie into the 4" drain that currently exists and exits the house. The floor drain, shower floor drain, and washer drain will be 2", as well as the sink and the utility sink until it gets to the p-trap.

    All help (especially sooner than later!) would be greatly appreciated, as I am starting this Saturday morning.

    Thanks again,

    Attached Files:

    Last edited: Sep 27, 2012
  2. Tom Sawyer

    Tom Sawyer In the Trades

    Messages:
    3,307
    Location:
    Maine
    About half of that drawing is wrong. In a forum like this it is impossible to thoroughly explain the principals behind wet venting. I don't know where you got that 12' from but it does in no way apply to what you are doing there. doing it without a permit and inspections would be a very bad thing to do indeed.
  3. jimbo

    jimbo Plumber

    Messages:
    8,997
    Location:
    San Diego
    You cannot wet vent a utility sink or a washing machine. The shower also is not vented
  4. Terry

    Terry Administrator Staff Member

    Messages:
    15,412
    Location:
    Bothell, Washington
    The sink on the far left is vented.

    Everything else needs some serious work to be called plumbing. Most of that is going to siphon everytime they get used. What do you have against venting? Vents are a good thing. They prevent siphoning of the p-traps. When the traps siphon dry, you can get the most horrible smells.

    Here is a nice link to Bert Polk's plumbing tips
    Last edited: Sep 27, 2012
  5. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    27,230
    Location:
    Cave Creek, Arizona
    The sink and toilet on the left side are okay, if installed the way you show them. EVERYTHING else is incorrect, as a "picky" inspector would tell you as he wrote out a rejection slip after he finished laughing at your installation. Putting a pipe in the middle of a line and calling it a "wet vent" does not make it so. As Abraham Lincoln once said, "If I call a dog's tail a foot, how many feet does the dog have?"
    Last edited: Sep 27, 2012
  6. Squints2See

    Squints2See New Member

    Messages:
    33
    Location:
    West by God Virginia
    I dont have anything against venting. I do however have limitations on where I can run the vents through the walls. Are you all saying that I need to vent each individual fixture and then tie them together a certain distance above the the highest fixture's flood level?

    Could you please explain how the shower is not vented?

    If the utility sink and washer cannot be wet vented, do I need to run a vent individually to those fixtures and tie them together above them?

    Could someone be so kind to show me what modifications need to be done to make this work?

    As far as permits and inspections, we are not trying to circumvent the system here, unfortunately in this state building practices are a joke and this includes the lack of permits and inspections. Very few towns here have any kind of inspections at all. I had an entire custom home built for me and no permits or inspections were required....lol
  7. Squints2See

    Squints2See New Member

    Messages:
    33
    Location:
    West by God Virginia
    HJ, would you be so kind to expound a little on everything to the right of the toilet being wrong? I also realize that this drawing does not show the details of the fixture connections to the 3" drainline, I am just trying to see if the overall layout is going to work.
  8. Squints2See

    Squints2See New Member

    Messages:
    33
    Location:
    West by God Virginia
    plumbing.jpg

    Is this better?
  9. Squints2See

    Squints2See New Member

    Messages:
    33
    Location:
    West by God Virginia
  10. Terry

    Terry Administrator Staff Member

    Messages:
    15,412
    Location:
    Bothell, Washington
    The shower is not vented. The vent needs to be between the trap and the line it connects to. Once a line has water running down it, it's a waste line. The toilet makes it a waste line, and the kitchen sink from above makes it a waste line.

    The floor drain needs a vent too.

    Vents can tie together at 42" above the floor. The vent from the basement either goes through the roof, or it can tie in on the second floor at 42".

    Here is a nice link to Bert Polk's plumbing tips
    Last edited: Sep 27, 2012
  11. Squints2See

    Squints2See New Member

    Messages:
    33
    Location:
    West by God Virginia
    Thanks Terry,

    I understand about placing the vent between the trap and the line. So basically you are saying that I cannot do any wet venting with my setup, that every fixture (except for the toilet) has to have its own vent? Can the floor drain not use the utility sink vent downstream as a wet vent as long as it is within a certain distance? And if so, what would that distance be?

    Thanks...
  12. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,313
    Location:
    New England
    My simplistic undersanding of wet venting is that it can only be used within a bathroom group - a utility sink and WM are not in a bahtroom group.
  13. Tom Sawyer

    Tom Sawyer In the Trades

    Messages:
    3,307
    Location:
    Maine
    A
    [/QUOTE]


    Yes you are trying to circumvent the system. I guarantee you that permits are required and just because your town may not have an inspector or a building department doesn't mean you don't need plans, permits and inspections. If your town does not have the facilities to do it than the state plumbing board does and they are the ones you need to contact. Furthermore, someone with your lack of plumbing knowledge and experience has no business even attempting a project like that without the guidence that an inspector and the permitting process afford you. We (and other diy sites) can give you all kinds of advice but without knowing exactly what the site looks like, without having exact measurements and knowing how the framing is situated and mostly without knowing you level of skill you are facing an uphill battle.

    Licensed plumbers protect the health and safety of the public. Improperly installed plumbing can and often will cause others sickness and in extreme cases death. That's why we are licensed and that's why the permit/inspection process is so important.

    http://www.reedconstructiondata.com/building-codes/west-virginia/

    http://www.cityapplications.com/building-permits/WV-West-Virginia/bldg-West-Virginia.html

    http://www.wvlabor.com/newwebsite/Pages/FAQs_plumbers.html
    Last edited: Sep 28, 2012
  14. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    27,230
    Location:
    Cave Creek, Arizona
    You have no concept of what "wet venting" means or is. The toilet on the left side is wet vented by the sink, but there is nothing on the right side which can be called a "wet vent". The toilet flowing past the shower and floor drain connections is what creates the need for a vent, and a vertical pipe in the proximity of a drain connection does not necessarily mean it IS a vent for it.
  15. Squints2See

    Squints2See New Member

    Messages:
    33
    Location:
    West by God Virginia
    How about this

    Ok, will this work?

    If my floor drain trap arm is within a certain distance of the washer vent can I wet vent with it now that I am connecting the floor drain downstream? Or, do I still need to have the floor drain vented separately as shown optionally below?

    How many feet does the toilet arm need to be from the sink vent to maintain the ability to wet vent the toilet?

    Thanks...

    Attached Files:

    Last edited: Sep 28, 2012
  16. Terry

    Terry Administrator Staff Member

    Messages:
    15,412
    Location:
    Bothell, Washington
    The lav on the left should be run with 2" pipe, including the vent.
    Make sure the floor drain is vented. Having the toilet and the washer running by it, it needs the vent.
  17. jimbo

    jimbo Plumber

    Messages:
    8,997
    Location:
    San Diego
    You show the shower drain, and the optional floor drain vent, as being horizontal.....a big no-no
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