Regardless, it goes vertically down into a horizontal line through a sanitary tee.

Sanitary tees are approved for use from horizontal into vertical - P3005.1 and Table P3005.1, IRC.

Plus, you wrote up that exposed facing on the insulation, right?

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Jerry Peck, Construction / Litigation Consultant
Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )