Plumbing Venting Example

[John_187]

Hello, I want to know if the attached file is a legal plumbing waste and vent setup? There is a row of individual vented lavs and a row of individual vented urinals upstream of a couple floor drains. The floor drains aren't individually vented. The main pipe connection to the floor drains is horizontal and it is 4". I assume it could just be defined as a combination waste/vent and/or wet vent. This is a project I inherited. Please help, thanks

 

[bimr]

Each building in which plumbing is installed shall have at least one main vent no smaller than 3 inches for each building drain installed.

Underground floor drains connected to a building drain or a building sub‑drain within 4 feet of a stack shall be individually vented.

You don't need individual vents on each fixture. Reference the link:

[link ftp://www.ilga.gov/jcar/admincode/077/07700890ZZ9996kyR.html]Battery Venting[/url]

Refer to the comments on your other posting.

Some example illustrations:

[link ftp://www.ilga.gov/jcar/admincode/077/07700890sections.html]See Appendix K[/url]

 

[John_187]

To clarify your response, you're saying these floor drains do need individual vents, or don't?

Could they be treated as combination waste/vent and/or wet vent?

Thanks

 

[PEDARRIN2]

Combination drain and vents (CDV) are a "gray" area in my opinion, where the AHJ may take a conservative view (more venting is better) or a liberal view (some venting is sufficient).

What you have drawn would likely fall in the middle - so should be ok. You did not indicate the drain size within the lavatory bank. To be a CDV system, it should be 2" all the way up one of the lavs and the vent needs to continue as a 2".

The urinal bank cannot be used as part of the system since urinals are not listed as acceptable for a CDV.

On a side note, there is a Plumbing forum on the site.

 

[bimr]

My opinion is that you need individual traps, but you can confirm with the AHJ.