I`m doing a plumbing job on new construction. Owner wants to use studer valves instead of through the roof vents for the whole house. I plan to run the vent pipes into the attic
And put the studer vents on there. This is a two bath and kitchen and washer box.
Will this be OK in Tenn.

If not what's the best way to cut vent holes in a metal roof?

You'll have to check local codes in your area for the answer. Some will allow AAV's and some some won't. Check with your Building Deptment. If you would like a opinion, let me state that we use AAV's when it's impossible to run a regular vent. As with any mechanical devise there's the very real possibility that they will go bad in time. That can't happen with a regular vent. If for no other reason I would try to talk the home owner out of the idea. Good luck, Tom