Well, I bought two Toto Drake toilets based on recommendations here.
I seem to be having a problem with one of them, it just plain isn't flushing very well. This is the toilet in my addition. Upon climbing on the roof I don't see any venting, which I suspect is the cause.
The toilet in my main bathroom flushes excellently. The toilet goes right into the main 3" stack.
From what I can tell there were no permits on my addition - I don't think they would have allowed the bathroom in it with no venting and there's no heat runs in it at all.
That aside, I did find a 1.5" cheater vent on the sink. The 3" drain pipe runs about 40' into the main drain.
I'd like to fix this properly and have already contacted a roofer to deal with the torch-on roof. What I'm not sure about is what size of a vent and where I should put it. I could extend the drain pipe one foot and put a vent up the wall, so the vent would be upstream. I could do the same on the other side and attach the sink to it, so it'd be about a foot downstream.
Toilets don't need a full 3" vent, do they?