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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.

Referenced article content

What the cited source says

This is a StairSolver summary of the cited source content, written in plain language so you can understand the rule before opening the official reference.

  • The cited IRC baseline treats landings as required flat space at stair starts, ends, and turns.
  • StairSolver uses a 36-inch landing-depth baseline when checking whether a turn layout has enough usable flat space.
  • The source supports a landing-depth warning, but door swings, walls, and local amendments can change the final review.

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?

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.

Official source links

Check the original source if you need the authority trail

These links leave StairSolver. Use them when you want to verify the official citation, then come back to the calculator to test your dimensions.

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