Venting multiple fixtures in a public restroom 2

[jay156]

Hi, I have a question. I'm working on a bathroom addition for an exposition center, and right now have a vent coming up from each toilet and each sink. But now the plumber tells me that not every fixture needs to be vented. Is that true? I guess what he's proposing is a vent only at every other toilet, (typical 3' wide stalls), or possibly further separated. If that is allowed, how far apart do the vents need to be spaced?

Thanks for your help.

 

[PEDARRIN2]

The simple answer is the plumber is correct.

All fixtures with traps must be vented, but the method of venting does not require that each fixture have a vertical vent pipe connected to the drain pipe.

Without a diagram to see what the plumber is proposing and what code has jurisdiction - it is impossible to say one way or another.

 

[sspeare]

You might want to study the "VENTS" chapter in the International Plumbing Code (IPC). Vents are in chapter 9 in the 2009 edition of the IPC. Also, some local jurisdictions amend the IPC, or adopt their own Plumbing Code.

 

[jay156]

Thanks guys, I looked up chapter 9 and researched the terms. I think what he wants to do is use a "circuit vent." It's a rectangular room with 6 water closets on the east and west wall, then three lavatories on the east wall to the north of the WC's. Like this:

LAV
LAV
LAV

WC WC
WC WC
WC WC
WC WC
WC WC
WC WC

One other question is can the soil stack be used as the vent in this situation, or does there have to be a separate stack to act as the vent?

The code is the Ohio Plumbing Code which is pretty much the 2006 IPC I believe.

Thanks for your help.

 

[sspeare]

Re: Circuit Venting - see the attached file on how to do it. The file is from the "Commentary" to the 2003 IPC. NOTE! This attachment is from the 2003 Plumbing Code. I do not have the "Commentary" to the 2009 IPC yet. So, watch out!!! Some drawings may have changed in the 2009 Commentary. You should probably buy the Commentary to the 2009; I've been delaying buying it myself, because work is so slow, but ......

You will probably find the answer to your combined soil stack/vent question in the attached file.

 

[PEDARRIN2]

Circuit vents only work for floor mounted water closets and individual circuit vents are constrained to 8 fixtures each.

If the toilets are wall hung, the carriers will have vents. Each back to back water closet can be vented together. The lavatories would be individually vented, but could combine 6" above the flood level rim of the fixture and a single vent could rise from that.

You can bring a single stack up from the sanitary and it could act as a the vent riser.

You do not need to buy the 2009 IPC commentary yet - Ohio hasn't adopted the 2009 IPC yet. The 2006 commentary will work. I use the 2003 commentary since not a whole lot has changed in the 2006 code.

 

[jay156]

Thank you both, you've helped me greatly. I think I now understand what needs to be done.