Hello all you plumbers,
I am remodeling my kitchen and moving my sink from an interior wall to a exterior adjacent wall under a window. The current vent services only the kitchen draIn and goes up two stories to the roof above. Can I put in a new vent that goes up to the first level overhang vice all the way up? I live in Hawaii. Is there a minimum length for the vent?
Thanks
jmartin015

Nope, can't vent to the eave of the home. You need to get ABOVE the roof line. In a pinch some folks try using an AAV which may not be legal in your state. AAV are also called Studor vents or cheaters

Thanks, I guess I can use the existing vent and just run it horizontal and connect before the turn in the wall. I will check the AAV solution as well.

Before you can can change vent from veritcal to horizontal you must be 6" above flood level of kitchen sink. If legal in your area, Oatey makes 1 1/2" trap with AAV on it. It is the same as 1 1/2" trap with a opening to screw AAV on it.

Let's keep this simple. Call your local Building Department and ask if AAV's are legal in your area. If they are simply tee one on behind your trap. (see image). Good luck, Tom

Thank guys. I have been told by a contractor that AAV's are not allowed here. But I want to put one in anyway along with the original vent. So the AAV will vent about 4 ft up to where the original vent connects (right after the 90 degree turn) downline. I may have to buy one online though, any suggestions about a brand name or type?
BTW, it is near impossible to find a phone number on line for the county builders code people. I guess they just don't want to be bothered. Lol

Hi Jmartin

There is absolutely no need for an AAV here if you are connecting into the original vent.

Not only is it illegal in your area, but an AAV must remain accessible for future swap out should the AAV fail. Never mind that it just isn't necessary if you tie into the original vent.

Just be sure to pipe the vent so it has some pitch, and keeps that pitch, from the original vent back to the sink, OK?

Good luck!

Mark

Hi Jmartin

There is absolutely no need for an AAV here if you are connecting into the original vent.

Not only is it illegal in your area, but an AAV must remain accessible for future swap out should the AAV fail. Never mind that it just isn't necessary if you tie into the original vent.

Just be sure to pipe the vent so it has some pitch, and keeps that pitch, from the original vent back to the sink, OK?

Good luck!

Mark

OK, thanks. I will pitch the vent at 45 degress from the verticle cutoff into the 2" drain pipe as it comes around the 90 degree corner bend.

Appreciate the help. I was also going to have a trap under the sink and leave a trap (original trap) at the point where the drain goes down into the floor.