I previously posted on cutting a cast iron pipe to tie in a vent line,
but I might have an alternative to avoid doing this, so here is my
dilemma.
In my kitchen soffit runs a vent line horizontally (parallel to the
soffit) that picks up the 2 bathrooms on the upper level of my split
level house. This vent line ties into the main waste stack in the
soffit. I would like to eliminate the soffit, which means re-routing
the vent line. Can I route the vent line up to the attic between the
wall studs, go horizontal, then back down again between the wall studs
to tie into the main stack?