Venting the kitchen!

I'm getting ready to do my kitchen and have some very basic questions about venting! First I'm in Northern NJ, and the house is old -- from about 1880. The kitchen has not been done since maybe the 1950's. I currently have one sink on the outside wall, but they did not do a very good job at venting and I believe it is not currently up to code. Right now the sink is vented straight out horizontally from the drain pipe thru the outside wall, and opens below the window above the sink! So I think for starters thats a no-go. I'll be gutting the kitchen so I can instead run the vent up the wall and out the roof above the sink.

Here's big question #1: the house is two stories with the kitchen on the first floor of course. Part of the the kitchen roof above the sink is actually a shed roof for the first floor only, and there's two bedrooms (and two windows) above the shed roof (sketch attached). Can I run the kitchen sink vent up thru the outside wall and vent thru the shed roof? Is there a distance it needs to be from the bedroom windows above? Or is a horizontal vent thru the outside wall ok, so long as it is above the kitchen window above the sink?

Question #2: I plan to also add a peninsula with a prep sink (shown in sketch). I think the preferred way is an island vent that ties in to the outside vent for the main sink on the outside wall? Also read a bit on AAV's. But from what I've seen these are only permitted in NJ if signed off by an architect or engineer?

I plan on doing most if not all the work myself. and in NJ the homeowner can act as his own architect/engineer (built my own addition a few years back and served as GC, engineer, architect and carpenter so I learned the ropes a bit).

Let me know what you think! Appreciate the help as always. U guys got me thru the addition with flying colors! john p

 

Pretty sure the island sink will need to be piped like this...



The venting I believe is 3 ft from a window, or opening...

But always ask your local code authority for verification...

In NJ here I dont think they allow studor vents on the islands... Its what I remember but I could be wrong as could changes with the times..

 

thank you -- and will check locally for sure. So i can run the vent out the lower shed roof so long as it is 3' from either of the second story windows above? that would be great. And yes on the island -- i'll run it to the line for the main sink.

 

When you submit the plans for permits they will let you know, but IMO go down to the town and ask the plumbing inspector... He/they may want something different...

 

For what it's worth, I remodel all types of kitchens. Every island I've seen is plumbed like Mike's diagram in post 2.
The very top 90° elbow (loop) should be as high as possible and the diagram reflects that.
The sanitary tee for the trap should be lower than shown. You want room/height to install a deep sink, a trap, a baffle tee (for any disposer).
If you place the center of the sanitary tee about 14 to 15" above the finished floor, you should be good for any type of sink and disposer.

 

great thanks all for the input!

 

hi again and one more on this -- can I vent thru the wall vs roof so long as I respect distances to windows etc? is there a specific vent cap used for this sort of thing? thx again!

 

Looks like you got most of the info you need. When you vent up that wall, you'll likely need to turn into the ceiling area a foot or two, then vent through the roof. To get a good seal in the roof, you won't want the pipe coming up right at the edge of the roof.

Definitely talk to the plumbing inspector first though. Bring that sketch and a floor plan of the kitchen and make sure your plans meet what they expect. Every town in NJ has its own peculiarities, so it's good to make sure you're doing it right the first time.