Venting Question

[MartinR]

I live in California, so we are under the UPC code. I'm plumbing a new construction and would like to tie all the vents together so they exit at one point from the roof. I have a metal roof, and figure by venting at the ridge I can better flash this with a roof jack to prevent water intrusion. I'm not sure this is allowed unders the UPC code. Can reventing be done at all under the UPC or must every vent have it's own roof penetration?

Thanks, Marty

[hj]

You must have at least one, but other than that you can have as many, or as few, as you want. The important thing is that the vent has to be properly sized as the various pipes combine.

[MartinR]

Thanks for the reply. SO then I could say run my kitchen sink vent into my main stack vent? Can this be a horizontal run or does it have to tie in at a 45 deg angle?

Marty

[hj]

Horizontal with 1/4" per foot slope.

[MartinR]

Thanks HJ,
So I'm getting conflicting info. From another forum I got a response that says
The UPC does not allow any flat horizontal venting. The maximum angle for an offset is 45 deg. from vertical and all vents must terminate through the roof.
I found part of the UPC code on line, and section 905 seems to allow horizontal venting. What gives?

Thanks, Marty

[hj]

I do not know where you are getting your information, but I have been installing horizontal vents for 55+ years.

[MartinR]

Sorry Hj didn't mean to question your expertise, there is just alot of confusing information out there on the net.

[Terry]

Perhaps they were thinking of venting below the flood level of the fixture.

Vents can combine at 6" above the flood level, which would be 42" on a kitchen sink.