shower vent ?

I am adding a basement bath, utility sink and washer.

I had a plumber out today and he said I could use the existing first floor tub/shower vent to vent my new basement fixtures. The 2" cast iron that's connected to the red fitting is the vent line. This line goes through the roof. There are no other fixtures connected to this vent.


He said I can do this because the 2" PVC drain that you see in the photo is within 8 feet of the main stack.
The drum trap and the cast iron fitting will be removed.

Just doing my homework on this guy. Does a tub/shower have to have a vent if it drains within 8 feet of the main stack?

I live in Missouri.

If there are any fixtures connected to the main stack above the shower connection, then the shower needs it's own vent.

no. vent bathroom to outside, no matter how hard you think it is. you'll create more problems by putting it.