I am installing a basement bathroom (sink, toilet, tub) and curious about venting properly. I am going to run a 2 inch vent up past the sink drain. I would like to know how to properly vent toilet behind the toilet flange, going up into the wall that will be built behind it. I've attached an example of what I would like to do to vent the toilet. I would like solutions not just know what is wrong. Also do I need a separate vent for the tub?