Stair building guides
Field-tested walkthroughs that pair with the calculator.
How to calculate stair risers and the number of steps
The formula that turns a floor-to-floor height into a step count and riser height, a worked example, a reference table, and the off-by-one mistakes to avoid.
How to calculate and cut stair stringers
Calculate stringer length from rise and run, then lay it out: framing-square setup, gauge blocks, dropping the stringer, and the two cuts everyone gets wrong the first time.
Stair building code requirements, explained
What IRC R311.7 actually requires (riser, tread, width, headroom, handrails, and the ⅜″ uniformity rule) and where local codes commonly differ.
The 2R + T rule: why stair comfort is a formula
A 350-year-old equation still governs how stairs feel underfoot. Where Blondel's rule comes from, when to bend it, and how it interacts with code limits.