I'm finishing off the vacant third floor of my house in St. Louis, Missouri and adding a bathroom and (hopefully) a bar with a sink. The stack was roughed in at the time of original construction to include a sanitary tee for the bathroom sink. As I understand things, since the trap for this sink will be within five feet (2' actually) of the main stack it would be considered self venting and no additional vent would be needed. However, I would like to add a bar sink a little farther down on the opposite side of the wall which will require extending the horizontal drain line an additional four feet for a total of about six feet from the trap to the stack. I assume that I'll need to install a dry vent for the bar fixture (farthest away from stack), but would like to confirm that its okay to wet vent the bathroom lav fixture (nearest the stack) on the same 2" line.