[tjp1]

I'm buildinga barn with the center section 24 foot wide and 2 stories. A 12 foot wide single story lean to will be on each side of the center section. One lean to will contain a bathroom, kitchen, and a washng machine. I'm planning on having a second story bathroom also. Is it advisable to run the 3 inch vent stack for the first floor through the concrete footing of the center section to pick up the second floor bathroom? The 2 inch standpipe for the kitchen sink, which is on an outside wall, will also have to be run through a concrete footing. Is this OK? Does anyone have a DWV layout for a typical bathroom? A kitchen? Thanks in advance for your help.

[speedball1]

I'm planning on having a second story bathroom also. Is it advisable to run the 3 inch vent stack for the first floor through the concrete footing of the center section to pick up the second floor bathroom?

Do you mean concrete flooring or a concrete support beam? If you're asking if you can stack one bathroom group over another using the same stack vent the answer's yes, but only if you run a individual off the doiwnstairs lavatory and revent it back into the vent stack at least 6" over the flood rim of the second story lavatory.

The 2 inch standpipe for the kitchen sink, which is on an outside wall, will also have to be run through a concrete footing.

Please explain "concrete footing" Are you talking about the foundation? I know of no other "footings".

Does anyone have a DWV layout for a typical bathroom?

Most bathroom groups are roughed in like this.
Toilet connects to sewer main or the stack vent. Lavatory connects to toilet drain and runs a vent off the top the stubout tee out the roof or revents back into a dry vent in the attic.. The toilet wet vents through the lavatory vent and the tub/shower connects to the lavatory drain and is wet vented by it. This is a normal rough in and is acceptable both by local and state codes and also The Standard Plumbing Code Book in 90 percent of the country. Check your local codes.to make sure you're not in the excluded 10 percent.. The vent off the lavatory may be run out the roof or revented back into a dry vent in the attic or if you're reventing back into a fixtures dry vent you must make your connection at least 6 inches over that fixtures flood rim.
The kitchen must have it's own trap and vent out the roof or revented back to a existing dry vent. Good luck, Tom