Hi, we are remodeling our bathroom and want to install a large recessed medicine cabinet above the vanity. However, there is a vent pipe right in the way.

One solution would be to re-route the vent pipe as I have indicated in the attached picture. There are three fixtures vented: bathtub, sink, and toilet. All the changes would be made 6"+ above the flood line of the sink, which is the highest fixture. I would reverse the slope of the horizontal line where everything ties together, then run a 45 degree pipe up to intercept the original line much higher up on the wall (the bathroom has a cathedral ceiling).

Would this arrangement provide code-compliant venting?

Thanks for your help,

Tom