Calculate Open Staircase code compliance

[Leland S.]

I have an open staircase with mono-stringer and thick wood treads going in my new build. My architect provided some treads on the drawing which I took as gospel, now that I am ordering I am trying to verify everything meets code and it's a PITA. 

Everything comes in to meet codes using this calculator with specs below, except I don't know the above floors headroom yet, but I am confused by the total run of 202". I have a measured opening in the floor of 134". I'm sure the stringer could mount to the floor farther out, until the headroom is not met, but I think 60" over the floor opening is ridiculous. 

My floor system is 1.5" and ceiling height is 10', so 11.5' total. I have to go on site to measure the overhang distance still. 

The treads I was buying were 3" thick wood treads, but I realize I cannot meet the 4" sphere requirement. The min tread height is 7 1/8" - 7.75" so I used 7.5" rise height with a 3.5" thick tread.

Calling all experts so I order the right thing!

https://www.calculator.net/sta...