New house. I'd like to drop straight down from my toilet for about 16"-18", then turn horizontal via a 3" T-wye. (The upstream horizontal opening of the T-Y will have a clean out in it.) My question is: Can I vent the toilet on the vertical drop at A w/, say, a 3-3-2 Y, or do I have to vent on the horizontal run at B? Pls see pic. Thanks. john
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