> For the complete documentation index, see [llms.txt](https://resources.viewrail.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://resources.viewrail.com/code-compliance/stair-code.md).

# Stair Code

- [Open Riser Code Requirements](https://resources.viewrail.com/code-compliance/stair-code/open-riser-code-requirements.md): Learn open riser stair code requirements, including the 30-inch threshold, 4-inch sphere rule, and IRC riser height limits for floating stairs.
- [Winder Staircase Code Requirements](https://resources.viewrail.com/code-compliance/stair-code/winder-staircase-code-requirements.md): Learn winder stair code requirements, including IRC walkline rules, minimum tread depth, and winder tread uniformity.
- [Tread Depth and Risers](https://resources.viewrail.com/code-compliance/stair-code/tread-depth-and-risers.md): Learn stair tread depth and riser height code under IRC 2021, including minimum tread depth, maximum riser height, nosing rules, and the 3/8-inch uniformity requirement.


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