Building Code Glossary
Story: Building Code Definition
How the IBC 2009, IRC 2009, IFC 2009, IMC 2009 define story, 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
Story is a defined term in the International Building Code (IBC) 2009, in Definitions. The code's own words are: “That portion ofa building included between the upper surface of a floor and the upper surface of the floor or roof next above (also see "Basement," "Mezzanine" and Section 502.1). It is measured as the vertical distance from top to top of two successive tiers of beams or finished floor surfaces and, for the topmost …” The IRC 2009, IFC 2009, IMC 2009 define the same term with different wording, so the controlling text depends on which code governs the question in front of you — the comparison below sets the versions side by side. The term is used in 57 chapters of this corpus, most often in Wall Construction (IRC 2009), Wood (IBC 2009), General Building Heights and Areas (IBC 2009). These pages transcribe the 2009 model text; verify the definition against the edition and amendments your authority having jurisdiction has adopted.
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?
Story — IBC 2009, Definitions:
That portion ofa building included between the upper surface of a floor and the upper surface of the floor or roof next above (also see "Basement," "Mezzanine" and Section 502.1). It is measured as the vertical distance from top to top of two successive tiers of beams or finished floor surfaces and, for the topmost story, from the top of the floor finish to the top of the ceiling joists or, where there is not a ceiling, to the top of the roof rafters.
What must be verified before using this guidance?
Four of the I-Codes in this corpus define Story, and the wording is not identical — read the version that governs your question.
| Code | Where it is defined | Definition |
|---|---|---|
| IBC 2009 | Definitions | That portion ofa building included between the upper surface of a floor and the upper surface of the floor or roof next above (also see "Basement," "Mezzanine" and Section 502.1). It is measured as the vertical distance from top to top of two successive tiers of beams or finished floor surfaces and, for the topmost story, from the top of the floor finish to the top of the ceiling joists or, where there is not a ceiling, to the top of the roof rafters. |
| IRC 2009 | Definitions | That portion ofa building included between the upper surface of a floor and the upper surface of the floor or roof next above. |
| IFC 2009 | Definitions | That portion of a building included between the upper surface of a floor and the upper surface of the floor or roof next above (also see "Mezzanine" and Section 502.1 of the International BUilding Code). It is measured as the vertical distance from top to top of two successive tiers of beams or finished floor surfaces and, for the topmost story, from the top of the floor finish to the top of the ceilingjoists or, where there is not a ceiling, to the top of the roof rafters. |
| IMC 2009 | Definitions | That portion of a building included between the upper surface of a floor and the upper surface of the floor next above, except that the topmost story shall be that portion of a building included between the upper surface ofthe topmost floor and the ceiling or roof above. |
Where story is used in the code
The term appears in 57 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next.
| Chapter | Code | Mentions |
|---|---|---|
| Wall Construction | IRC 2009 | 128 |
| Wood | IBC 2009 | 83 |
| General Building Heights and Areas | IBC 2009 | 64 |
| Fire Protection Systems | IBC 2009 | 54 |
| Fire Protection Systems | IFC 2009 | 52 |
| Accessibility | IBC 2009 | 49 |
| Means of Egress | IBC 2009 | 40 |
| Building Planning | IRC 2009 | 33 |
| Means of Egress | IFC 2009 | 31 |
| Structural Tests and Special Inspections | IBC 2009 | 26 |
| Plastic | IBC 2009 | 24 |
| Special Detailed Requirements Based on Use and Occupancy | IBC 2009 | 24 |
45 further chapters mention the term.
The term in use
How the code actually writes about story, quoted from the 2009 text hosted here:
When exceeding 4 feet (1219 mm) in height, such walls shall be framed of studs having the size required for an additional story.
in both the longitudinal and transverse directions in each story.
A mezzanine or mezzanines in compliance with Section 505 shall be considered a portion of the story in which it is contained.
Story compared with Height, Story
These two are the closest pair in the 2009 I-Codes: about 52 per cent of their defining words are the same. The code states both and compares neither, so the difference is worth naming.
| Wording unique to it | |
|---|---|
| Story (IBC 2009) | portion, ofa, building, included, between, upper, surface, next, above, also, see, basement |
| Height, Story (IRC 2009) | ceilingjoists |
Everything else in the two definitions is shared. If a project turns on which of the two applies, those words are the whole of the test — and a local amendment that edits one of them without editing the other moves the boundary between story and height, story.
The terms story is built out of
The definition above leans on 4 other defined terms. Each carries its own code definition, and a local amendment to any of them changes what story covers:
- Mezzanine — IBC 2009: An intermediate level or levels between the floor and ceiling of any story and in accordance with Section 505.
- Building — IBC 2009: Any structure used or intended for supporting or sheltering any use or occupancy.
- Basement — IBC 2009: A story that is not a storyabovegrade plane (see "Story above grade plane" in Section 202).
- Shall — IRC 2009: The term, when used in the code, is construed as mandatory.
Story: 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 | Definitions | |
| Read the definition in the adopted IRC | Definitions | |
| Read the definition in the adopted IFC | Definitions | |
| Read the definition in the adopted IMC | Definitions | |
| Re-check the requirement that uses it | Wall Construction (IRC 2009) | |
| Re-check the requirement that uses it | Wood (IBC 2009) | |
| Re-check the requirement that uses it | General Building Heights and Areas (IBC 2009) | |
| Re-check the requirement that uses it | Fire Protection Systems (IBC 2009) | |
| Confirm the dependent definition | Mezzanine | |
| Confirm the dependent definition | Building | |
| Confirm the dependent definition | Basement | |
| 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
- Mezzanine: Building Code Definition
- Building: Building Code Definition
- Basement: 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 story?
The International Building Code (IBC) 2009 defines it in Definitions as: “That portion ofa building included between the upper surface of a floor and the upper surface of the floor or roof next above (also see "Basement," "Mezzanine" and Section 502.1). It is measured as the vertical distance from top to top of two successive tiers of beams or finished floor surfaces and, for the topmost story, from the top of the floor finish to the top of the ceiling joists or, where there is not a ceiling, to the top of the roof rafters.” 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.
Do the I-Codes define story the same way?
No. IBC 2009, IRC 2009, IFC 2009, IMC 2009 all define the term, but the wording is not identical, and a difference in wording can change which requirements are triggered. The comparison table above sets the versions side by side so you can read the one that governs your question.
Which parts of the code depend on story?
In this corpus the term is used across 57 chapters, led by Wall Construction in the IRC 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 counts as a story for a building?
In the 2009 I-Codes hosted here it is a defined term rather than a description. The IBC 2009 states, in Definitions: “That portion ofa building included between the upper surface of a floor and the upper surface of the floor or roof next above (also see "Basement," "Mezzanine" and Section 502.1). It is measured as the vertical distance from top to top of two successive tiers of beams or finished floor surfaces and, for the topmost …” It is defined in IBC 2009, IRC 2009, IFC 2009, IMC 2009. It is not the same as Building, which the IBC 2009 defines separately as “Any structure used or intended for supporting or sheltering any use or occupancy.” 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.
Is a basement considered a story in IBC?
In the 2009 I-Codes hosted here it is a defined term rather than a description. The IBC 2009 states, in Definitions: “That portion ofa building included between the upper surface of a floor and the upper surface of the floor or roof next above (also see "Basement," "Mezzanine" and Section 502.1). It is measured as the vertical distance from top to top of two successive tiers of beams or finished floor surfaces and, for the topmost …” It is defined in IBC 2009, IRC 2009, IFC 2009, IMC 2009. It is not the same as Basement, which the IBC 2009 defines separately as “A story that is not a storyabovegrade plane (see "Story above grade plane" in Section 202).” 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 does story stand for?
In the 2009 I-Codes hosted here it is a defined term rather than a description. The IBC 2009 states, in Definitions: “That portion ofa building included between the upper surface of a floor and the upper surface of the floor or roof next above (also see "Basement," "Mezzanine" and Section 502.1). It is measured as the vertical distance from top to top of two successive tiers of beams or finished floor surfaces and, for the topmost …” It is defined in IBC 2009, IRC 2009, IFC 2009, IMC 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.
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