What width stringer should I use for this to meet strength requirements? I'm building stringers using joinery something similar to https://i.pinimg.com/originals/c1/79/a8/c179a88f9dbbbe7666a2d5f7d07e997b.jpg I think 2x12's are going to be too thin to serve as a stringer. I plan to router out the size of the step 1 inch deep + create a hole for a 2x4 sized poke through like this picture. What am i looking for here in terms of stringer width 3x12? 4x12? I could do 2x12 with a supporting spine straight board. I called the inspector to pre approve the project before I went down this path. One guy said yes,he retired, I showed a mock up and the next guy said no, stringer violates IBC chapter 10 Stairs. Theyre closed for covid and I'm still waiting on an answer. Ive read chapter 10 repeatedly, I don't see the stringer violation.