South Dakota Building Codes: Stairs & Guards

South Dakota has no mandatory statewide residential building code. Whether the IRC applies to your project — and which edition — depends entirely on whether your city or county has adopted one, and if so, when and with what amendments.

There’s no single figure set to point to here. Where a local jurisdiction has adopted the IRC, a house stair typically follows the standard figures — 7¾ in max riser, 10 in min tread, 6 ft 8 in headroom, 36 in min width, 34–38 in handrails, 36 in guards, the 30 in guard trigger and the 4 in sphere — see the US stair & guard rules. But treat those as a starting point only: check with your city or county building department for the edition and amendments actually in force before you build.