# BOCA Question



## gladerunner (Jan 24, 2009)

Hey all you BOCA guy's, quick question. (And plese don"t kill me I never work with BOCA). Running a new horizontal branch for kitchen sink. Approxamately 35' from suspended main drain in basement to new sink location. Will vent straight up behind sink through roof. Question is, can horizontal branch line be 1-1/2" or do I need to run 2" up to P trap with 
1-1/2" vent from there?


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## CTs2p2 (Dec 6, 2011)

I can't find my BOCA book.. 

I want to say 2" but not sure..


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## coast to coast (Feb 17, 2012)

Just a guess but I'm going to say 2" also . Will be interested to find out and I'd also guess that the only thing u can run in 1.5" is a trap arm . Under the boca code anyways .


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## Michaelcookplum (May 1, 2011)

2"!


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## drain surgeon (Jun 17, 2010)

Why not just run 2" and be sure ? Even if code is only 1 1/2 code is Minimum


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## coast to coast (Feb 17, 2012)

drain surgeon said:


> Why not just run 2" and be sure ? Even if code is only 1 1/2 code is Minimum


Good point . My rule of thumb on a k.s. Is 2" . Just the way 1 j man taught me to do it when I was coming up .


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## Epox (Sep 19, 2010)

Another way to interpret code is simply "the least and sorriest way you can do something and get away with it". So if 1.5 is acceptable run 2", especially being a KS.


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## ironandfire (Oct 9, 2008)

I'd run 2" and support every two feet.


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## ToUtahNow (Jul 19, 2008)

Where are you still using BOCA? The 1.5" line would be legal but I never run anything smaller than 2".

Mark


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## Tommy plumber (Feb 19, 2010)

coast to coast said:


> Good point . My rule of thumb on a k.s. Is 2" . Just the way 1 j man taught me to do it when I was coming up .


 





Same here. I was taught that 2" was the minimum size for DWV below the slab. Why would anyone want to install 1 1/2" or 1 1/4" below grade?


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## plumber666 (Sep 19, 2010)

So, what's BOCA?


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## CTs2p2 (Dec 6, 2011)

http://en.wikipedia.org/wiki/International_Building_Code

Thought it would be a good time to see if I know how to post a link, that works...


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## gladerunner (Jan 24, 2009)

Thanks for all reply's. Spoke with inspector. Said 1-1/2" would be OK. 4x1-1/2 wye was already was installed and would have been difficult to cut out. Thats why I wanted to stay 1-1/2"


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