I am in the process of installing a basement bathroom that will utilize a sewage ejector system since the sewer main line is above the floor. Since there is no easy chase to run a vent line three stories up to the roof, can I vent through a side exterior wall of the house? Can the line be capped off horizontally or must it end in a vertical run?

Is it possible to use an auto vent type valve for the system ( the type used for some sinks?)

Thanks for any help that can be offered.

The mechanical vent you may be thinking of is a Studor Vent.