Kitchen Sink Venting

[goober23]

I have a quick question regarding the remodeling of my kitchen. I have an 85 yr old home that has the 1.5" vent pipe coming up out of my kitchen counter and going up into the ceiling and taking a few turns before exiting the roof. I am planning on ripping out the plaster, reworking the wiring and hiding the vent in the wall as well as insulating. I am wondering if I should use a 1.5" or 2" vent for this sink with disposal and dishwasher when I tuck the piping into the wall. The old drainpipe is galvanized which is shot and needs to be pulled. Also, does it matter if the vent pipe exits the roof midway up, or do I need to direct the vent out at the peak as it is currently set up? And what size would I need to bump the vent up to at the roof to prevent freezing/frosting over during the cold Wisconsin winters? Any advice would be helpful.

[RioHyde]

Not sure what the code requirements for Wisconsin are, but here in Ohio minimum size for the k/s drain is 1-1/2" and vent 1-1/4" (though to see 1-1/4" used here is nearly unheard of). Also, the vent size must increase to 3" twelve inches below and twelve inches above the roof.

All that being said, something to chew on.....

Code requirements are only the minimum requirements and meeting minimum just sometimes isnt good enough in my own personal opinion. Kitchen sink drains drive me crazy. I'm getting ready to rerun my own kitchen sink drain and am going to pipe it in 2". Just an opinion and you know what they say about those, but I really feel like kitchen sink drains should be upsized to 2" per code.

As I said....just an opinion and not really wanting to invite debate. lol

[Terry]

RioHyde,
In the Western states using the UPC code, kitchens have been run using 2" pipe with 1.5" traparms.

[RioHyde]

Wish they'd adopt that here, Terry. I'm getting ready to rerun my k/s drain which is 1-1/2" and clogs on me about once year. I know, I know clearing a clog once a year may not seem like alot to some people, but you dont have to hear my wife griping about it while I'm snaking it out. lol!