I have seen it mentioned that a vent can be run horizontal. I have a basement bathroom and I'm planning to have a sink and shower on one side and a washing machine on the other and a toilet that is wet vent from the washing machine. I cannot run the vent on the sink and shower side of the room to the location where I am going to place the AAV without crossing a doorway. My question is, can i run the vent for the sink and shower up into the floor joists, horizontally across the room and down to meet up with the vent for the washing machine and then run the vent across the room perpindicular to the joists to the AAV? Thanks in advance.