i am adding a basement bathroom for my mom and have a couple of questions. the new bathroom toilet,showerstall and sink is going to be within five feet of the soil/waste stack already existing for the upstairs. i was planning on running a new vent along side the existing vent because there is a place i can run in through behind the sink in the 2x6 wall and then through the roof. i was wondering can i vent the sink, shower, and toilet through the vent,or if the toilet is within 5 feet of the waste/soil stack would that be considered venting? when venting the sink and shower does it matter which is vented higher on the vent stack? thanks