Kitchen Remodel Assistance

[blues327]

Afternoon All,

The wife and I are going to performing a full gut on our mid-sixties split entry. One of the possible issues we will be encountering will be widening the window from 35.5 inches to 69 inches. Basically taking the double window from the dining room, where we are install french doors, and moving it to the kitchen for more natural light. The issue I am going to have is that the vent stack from the basement bathroom and kitchen is currently running from the basement to the roof just to the left of the current window. The new window will be occupying that space. Since we haven't taken out the old cabinets, I'm not sure of the exact size of the stack but I know that it is cast iron. If it is the 3 inches I believe it is, can I reduce it to 1.5 inches in order to run it horizontally through the new framed 2x4 walls then convert it back to 3 inch for the vertical run to the roof? Or would it be possible to vent it directly outside, horizontally underneath the window to one side, then run vertical again past the roof line?

 

[Terry]

The West Coast UPC allows three bathrooms on 2" as long as you have a combined venting for the home of either a single 3" vent, or a combination of two 2" vents and a 1.5" vent. those three make up the area of a 3" pipe.

 

[Sponsor]

 

[blues327]

The West Coast UPC allows three bathrooms on 2" as long as you have a combined venting for the home of either a single 3" vent, or a combination of two 2" vents and a 1.5" vent. those three make up the area of a 3" pipe.

I know that Nebraska follows IRC 2012 codes, per our local permit office. All 3 bathrooms, basement 3/4, main full, master 1/2 and the kitchen vent through 2 3 inch cast iron vents that are tied together via galvanized pipe in the attic. So, that makes sense. My goal would be to not reduce if I didn't have to, but if I had to I would only reduce down to 2 inch, which I could still safetly run through the new king and jack studs for the new window.

 

[Jadnashua]

You can't reduce the pipe size in the middle of a run. You can run multiple smaller pipes as long as you have the minimum required area of the combination, and later connect them to a single larger pipe to exit the roof if you want. Any horizontal section needs the same slope as a drain line or at least 1/4"/foot. So, could you run smaller pipes from things below, and then combine them later? As long as each individual branch is sufficient for what it is venting, you can later combine them so you only need one penetration through the roof, or, you could have multiple smaller ones. FWIW, because of the winter temperatures where you live, you may need a larger pipe to exit the roof to prevent hoar frost from closing it off.