dwv sizing

i'm installing a half bath...toilet & vanity....the vanity will be 1-1/4" to a 1-1/2' waste line...vented to the soil line vent.....can the toilet be a 3" flange/line to a 3" soil line and a 3" vent line....or is the toilet always a 4" flange and line........can the vent be 2"..... also a kitchen sink vent...can it be 1-1/2" or is 2" a minimum?

I live in massachusetts.

Need to know what code you are under.

upc....is it less restrictive than the international pc?

quote; upc....is it less restrictive than the international pc?

You[ve got to be kidding. The IPC is a "do whatever you want to" code. They cancelled their merger with the UPC when they discovered what they would have to do under the UPC.

You live in mass. They have their own code. It's closer to the old BOCA code than anything else. At any rate, you need to hire a plumber. Mass won't allow you to do your own plumbing.