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Riser height

Are my stair risers too tall?

A tall riser makes every step higher, which can make the stair harder to climb and can trigger baseline risk even when the stair looks simple.

The short answer

The current baseline flags riser height above 7.75 inches.

StairSolver uses this as a baseline planning check. If the measurement crosses the threshold, the report explains what number triggered the flag and what to ask before building, buying, or approving a plan.

Report boundary

Baseline risk, not local approval.The local authority, inspector, engineer, or qualified stair professional still decides the final answer for the exact property.

What StairSolver checks

Inputs used for this warning

  • floor-to-floor height
  • riser count
  • calculated riser height

User input fields: floor-to-floor height.

Why it matters

What problem this prevents

  • The total height has to be divided into a whole number of risers, so a small change in riser count can change whether the stair is plausible.
  • This is a good reason to ask the contractor to write the exact riser count and riser height into the plan.

What to ask before building

Questions generated from this risk

  1. Can you show the exact riser count and riser height before the layout is approved?
  2. If the riser is too tall, what layout change fixes it without making the tread too shallow?

Which official source is referenced?

Source citations

2021 IRC R311.7.5.1

Baseline residential stair check for maximum riser height.

International Code Council / irc-baseline-2026-07-01Open 2021 IRC R311.7.5.1

What this page cannot prove

Where the tool stops

  • It cannot say your local inspector will approve the stair.
  • It cannot verify finished floor thickness, old-house exceptions, or local amendments by itself.