# Re-routing plumbing vent stack for sink around new larger window



## tpthaler (Apr 7, 2010)

Hello,


There is kitchen sink under a 4' window and the window is going to be replaced with a with a much wider one. The venting / drain pipe is 2" ABS. From the P-trap the drain runs horizontally about 2' to a T. The top of the T vents straight out to the roof (about 6" from the edge of the window), and the bottom of course connects to the main drain line under the floor. The window that is getting installed is about 18" wider on the vent side. This means I need to re-route the vertical vent. My question is, can I make a C shape around the window using 45' elbows, or do I need to just turn it once go over a few feet and cut a new hole in the roof? Please see attached diagram of two separate options I am looking into.


----------



## moorewarner (May 29, 2009)

hmmm...that's a tough one, what does your plumbing sub recommend?

I'm sure some other folks will be along any minute that might have something more to offer. :whistling


----------



## mikeswoods (Oct 11, 2008)

The drawing with the black (45's-) is best---Did you know that there is a sister site for homeowners?

Go to the bottom of the page and click on DIYchat.

A lot of good folks over there--Asking questions like this will get you eaten by a bunch of licensed plumbers---Attack of the butt cracks--Look out!!!!


----------



## bwalley (Jan 7, 2009)

tpthaler said:


> Hello,
> 
> 
> I currently have a kitchen sink under a 4' window and I want to replace this window with a much wider one. My venting / drain pipe is 2" ABS. From the P-trap the drain runs horizontally about 2' to a T. The top of the T vents straight out to the roof (about 6" from the edge of the window), and the bottom of course connects to the main drain line under the floor. I am going to be installing a window that is about 18" wider on the vent side. This means I need to re-route my vertical vent. My question is, can I make a C shape around the window using 45' or 90' street elbows, or do I need to just turn it once go over a few feet and cut a new hole in my roof? Please see attached diagram of two separate options I am looking into.


I recommend you call a licensed plumber, do not use 90's.

Depending on where you are located your plumber may be able to use an AAV on it.


----------



## UALocal1Plumber (Jun 19, 2009)

Why would you recommend a provent over 90s?

Keith


----------



## Green & Gold (Nov 20, 2009)

How high is the flood rim of the kit sink? What state are you in? Typically, when you can't go across 6" (+) above the flood rim, you go straight up just below the window plate and put an LS 90 right (drill your holes/1/4" per foot like a drain/highest hole on the far right!), pipe across and put an LS 90 up (when you get past the window) and go out any way you want after you are 6" above the flood rim (I'd go straight up through the plate and tie back in in the attic to save the right studs from a second drilling back across/ my way means a much taller "C" - may not be feasible if you've got no attic space or flat roof). Reg 90's under the flood rim are not permitted here. 45's are a pain because your holes (drilled to the right) are also at 45's. Too much hacking of wood for me to use 45's there. Inspector here would hate that. He'd ask "Why in the hell didn't you just use LS 90's and pipe across at 1/4" per foot (like a drain) instead of hacking up the window studs?" Oh, that kitchen vent can be 1 1/2" here (not venting anything else right/or a wet vent?). Cut and reduce (save the studs when drilling) to 1 1/2 if per code in your state (if UPC then no prob). Goof luk!


----------



## Ponderosa West (Mar 28, 2010)

Green & Gold said:


> How high is the flood rim of the kit sink? What state are you in? Typically, when you can't go across 6" (+) above the flood rim, you go straight up just below the window plate and put an LS 90 right (drill your holes/1/4" per foot like a drain/highest hole on the far right!), pipe across and put an LS 90 up (when you get past the window) and go out any way you want after you are 6" above the flood rim (I'd go straight up through the plate and tie back in in the attic to save the right studs from a second drilling back across/ my way means a much taller "C" - may not be feasible if you've got no attic space or flat roof). Reg 90's under the flood rim are not permitted here. 45's are a pain because your holes (drilled to the right) are also at 45's. Too much hacking of wood for me to use 45's there. Inspector here would hate that. He'd ask "Why in the hell didn't you just use LS 90's and pipe across at 1/4" per foot (like a drain) instead of hacking up the window studs?" Oh, that kitchen vent can be 1 1/2" here (not venting anything else right/or a wet vent?). Cut and reduce (save the studs when drilling) to 1 1/2 if per code in your state (if UPC then no prob). Goof luk!


 
You can go with 90' just like what is said above. 90's are allowed for change in direction. Use the LS as well


----------



## KillerToiletSpider (May 27, 2007)

This thread is a hoot.


----------



## mikeswoods (Oct 11, 2008)

He went next door--Seems to be a good guy---Glad no one handed him his hat.--Mike--


----------



## KillerToiletSpider (May 27, 2007)

mikeswoods said:


> He went next door--Seems to be a good guy---Glad no one handed him his hat.--Mike--


Would I do that?


----------



## BuildersII (Dec 20, 2009)

*Pitiful homeowner! How dare you disturb our slumber!:w00t:*


----------

