Building Code Glossary
Stairway, Interior: Building Code Definition
How the IBC 2009, IFC 2009 define stairway, interior, where the wording differs, and which chapters depend on the term.
On this page
Last updated September 7, 2026 · Definitions quoted from the 2009 International Codes as transcribed in this site's building-codes collection, with the source chapter linked for each quotation. Usage counts are computed over the chapters hosted here, one copy per code. The [ICC code library](https://codes.iccsafe.org/codes) publishes the current model text and the [ICC adoption maps](https://www.iccsafe.org/advocacy/code-adoption-maps/) show which edition a jurisdiction has adopted; those sources control.
Direct answer
Stairway, interior is a defined term in the International Building Code (IBC) 2009, in Means of Egress. The code's own words are: “A stairway not meeting the definition of an exterior stairway” The IFC 2009 carries the same definition word for word, so the term means the same thing in each. The term is used in 7 chapters of this corpus, most often in Means of Egress (IBC 2009), Means of Egress (IFC 2009), Building Planning (IRC 2009). These pages transcribe the 2009 model text; verify the definition against the edition and amendments your authority having jurisdiction has adopted. Record the jurisdiction, the adopted edition, the application date and any local amendment that rewrites the definition before you use it on a live project, because a term redefined by amendment changes every requirement that depends on it.
Content and cited inputs reviewed by Scott Barrington, Harth founder and architectural technology specialist · Published 2026-09-07 · Updated 2026-09-07.
What does this term mean?
Stairway, Interior — IBC 2009, Means of Egress:
A stairway not meeting the definition of an exterior stairway
What must be verified before using this guidance?
Two of the I-Codes in this corpus define Stairway, Interior, in identical words.
| Code | Where it is defined | Definition |
|---|---|---|
| IBC 2009 | Means of Egress | A stairway not meeting the definition of an exterior stairway |
| IFC 2009 | Means of Egress | A stairway not meeting the definition of an exterior stairway. |
Where stairway, interior is used in the code
The term appears in 7 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next.
| Chapter | Code | Mentions |
|---|---|---|
| Means of Egress | IBC 2009 | 8 |
| Means of Egress | IFC 2009 | 8 |
| Building Planning | IRC 2009 | 3 |
| Construction Requirements for Existing Buildings | IFC 2009 | 2 |
| Definitions | IBC 2009 | 1 |
| Definitions | IFC 2009 | 1 |
| Power and Lighting Distribution | IRC 2009 | 1 |
The terms stairway, interior is built out of
The definition above leans on 1 other defined term. Each carries its own code definition, and a local amendment to any of them changes what stairway, interior covers:
- Stairway — IBC 2009: One or more flights of stairs, either exterior or interior, with the necessary landings and platforms connecting them, to form a continuous and uninterrupted passage from one level to another.
Stairway, Interior: what to open, and in what order
Every row is a document this term depends on. The ICC code library and the ICC adoption maps cover the middle rows.
| Check | Where | Confirmed |
|---|---|---|
| Read the definition in the adopted IBC | Means of Egress | |
| Read the definition in the adopted IFC | Means of Egress | |
| Re-check the requirement that uses it | Means of Egress (IBC 2009) | |
| Re-check the requirement that uses it | Means of Egress (IFC 2009) | |
| Re-check the requirement that uses it | Building Planning (IRC 2009) | |
| Re-check the requirement that uses it | Construction Requirements for Existing Buildings (IFC 2009) | |
| Confirm the dependent definition | Stairway | |
| Local amendment to any of the above | Jurisdiction's amendment list |
A research aid, not a code determination. The authority having jurisdiction decides which edition and which amendments apply.
Where can you explore related guidance?
- Explore all glossary guidance
- Stairway: Building Code Definition
- Public Way: Building Code Definition
- Guard: Building Code Definition
- Stair: Building Code Definition
Sources and method
Definitions quoted from the 2009 International Codes as transcribed in this site's building-codes collection, with the source chapter linked for each quotation. Usage counts are computed over the chapters hosted here, one copy per code. The ICC code library publishes the current model text and the ICC adoption maps show which edition a jurisdiction has adopted; those sources control.
Source links
Frequently asked questions
What is the code definition of stairway, interior?
The International Building Code (IBC) 2009 defines it in Means of Egress as: “A stairway not meeting the definition of an exterior stairway” The 2009 model text is reproduced here; the definition that binds your project is the one in the edition your jurisdiction has adopted, as amended locally.
Which parts of the code depend on stairway, interior?
In this corpus the term is used across 7 chapters, led by Means of Egress in the IBC 2009. Those are the sections whose scope moves if the definition is amended locally, so read them together with Chapter 2 rather than on their own.
What is the code for a stairway?
In the 2009 I-Codes hosted here it is a defined term rather than a description. The IBC 2009 states, in Means of Egress: “A stairway not meeting the definition of an exterior stairway” It is defined in IBC 2009, IFC 2009. Because it is a defined term, whatever the adopted edition says it means is what every section using it means — so check Chapter 2 of that edition and any local amendment before relying on this wording.
What are the requirements for an IBC stair handrail?
Handrail is a separate defined term. The IBC 2009 defines it as: “A horizontal or sloping rail intended for grasping by the hand for guidance or support.” That is not the same as stairway, interior, which the IBC 2009 defines as “A stairway not meeting the definition of an exterior stairway” — read both before applying either, and confirm the wording in the edition your jurisdiction has adopted.
What does IBC mean in building codes?
Building is a separate defined term. The IBC 2009 defines it as: “Any structure used or intended for supporting or sheltering any use or occupancy.” That is not the same as stairway, interior, which the IBC 2009 defines as “A stairway not meeting the definition of an exterior stairway” — read both before applying either, and confirm the wording in the edition your jurisdiction has adopted.
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