Advice on rerouting plumbing vents for an attic remodel.

[Jamesboettger]

I am remodeling my attic and would like to have as much open space as possible. There are 2 plumbing vents in the attic that obtrude the space. One is a 4 inch cast iron pipe and the other is a 2 inch steel pipe. I would like to reroute or at least combine them. The house has 2 bathrooms. There is a third vent that is corrugated galvanized steel shown in the picture and I am not sure of it’s purpose.

 

[Jeff H Young]

cut pipe below floor 90 over to where you will build a wall travel up the new wall and through roof.