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Landing space

Is the landing space too tight?

A landing is the flat space where the stair starts, ends, or turns; if it is too tight, the layout can create a planning or inspection conversation before work starts.

The short answer

The current baseline flags landing depth below 36 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

  • flat landing depth
  • turn layout
  • door or wall conflicts

User input fields: flat landing space, clear floor length, room width available.

Why it matters

What problem this prevents

  • Small rooms often try to solve stair length by adding a turn, but the turn only helps if the landing itself has enough space.
  • This is why L-shaped and U-shaped options still need the landing depth and room width confirmed.

What to ask before building

Questions generated from this risk

  1. Can the landing depth be increased before the stair begins or turns?
  2. Can the layout show door swings, walls, handrails, and the exact turn landing?

Which official source is referenced?

Source citations

2021 IRC R311.7.6

Baseline residential stair check for top, bottom, or turning landing depth.

International Code Council / irc-baseline-2026-07-01Open 2021 IRC R311.7.6

What this page cannot prove

Where the tool stops

  • It cannot say your local inspector will approve the stair.
  • It cannot know every door swing, wall finish, or field condition without a measured plan.