Start normal stairs, draw run 1, draw run 2, mirror and position run 2.
Turn the first one into sketch based one and edit its shape. Good luck if it doesn't work as expected once you edit the shape.
do a stair by sketch of the bottom run, the landing and then the left side run. Then select the stair and mirror the whole thing copying it. The bottom be modelled twice but it will allow for your stringers and handrails to be continuous.
@barthbradley wrote:
Any idea why this keeps happening when I edit the sketch and add the curves? Run switches up/down direction.
There's only 2 Boundary Lines in my sketch...