I am Venting 2 sinks and a saniflo toilet. To prevent running a vent outside on the exterior of my house can I reduce the 1.5" vent line to 1" to run in a wall cavity with other plumbing lines? 1.5" won't fit around the other lines. Then back to 1.5" to connect to the line that runs through to the main vent stack. I live in Kentucky.
Thanks!
Thanks!