# Building: Building Code Definition

> How the IBC 2009, IRC 2009, IFC 2009, IMC 2009, IPC 2009, IECC 2009 define building, where the wording differs, and which chapters depend on the term.

- Canonical: https://harth.build/resources/glossary/building/
- Last updated: 2026-09-07
- Data source: 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.

## Key facts

| Fact | Value |
| --- | --- |
| Defined in | IBC 2009, IRC 2009, IFC 2009, IMC 2009, IPC 2009, IECC 2009 (2009 editions transcribed in this corpus) |
| Primary source | IBC 2009 Definitions (model text, not a jurisdiction's adopted text) |
| Chapters using the term | 162 (counted across the codes hosted here) |
| Wording identical across codes | No (compare before citing one code's wording under another) |

## Direct answer

Building is a defined term in the International Building Code (IBC) 2009, in Definitions. The code's own words are: “Any structure used or intended for supporting or sheltering any use or occupancy.” The IRC 2009, IFC 2009, IMC 2009, IPC 2009, IECC 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 162 chapters of this corpus, most often in Fire Protection Systems (IFC 2009), Special Detailed Requirements Based on Use and Occupancy (IBC 2009), Fire Protection Systems (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](https://nz.linkedin.com/in/barrington), Harth founder and architectural technology specialist · Published 2026-09-07 · Updated 2026-09-07.*

## What does this term mean?

**Building** — IBC 2009, Definitions:

> Any structure used or intended for supporting or sheltering any use or occupancy.

![Labeled code-term definition diagram: Building: Building Code Definition](https://efwwel0vyt9vy5so.public.blob.vercel-storage.com/images/glossary/building/diagram-1344.webp)

*How the IBC 2009, IRC 2009, IFC 2009, IMC 2009, IPC 2009, IECC 2009 define building, where the wording differs, and which chapters depend on the term.*

## What must be verified before using this guidance?

Six of the I-Codes in this corpus define **Building**, and the wording is not identical — read the version that governs your question.

| Code | Where it is defined | Definition |
| --- | --- | --- |
| IBC 2009 | [Definitions](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/definitions.md) | Any structure used or intended for supporting or sheltering any use or occupancy. |
| IRC 2009 | [Definitions](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/definitions.md) | Building shall mean any one- and two-family dwelling or portion thereof, including townhouses, that is used, or designed or intended to be used for human habitation, for living, sleeping, cooking or eating purposes, or any combination thereof, and shall include accessory structures thereto. |
| IFC 2009 | [Definitions](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/definitions.md) | Any structure used or intended for supporting or sheltering any use or occupancy. |
| IMC 2009 | [Definitions](https://harth.build/resources/building-codes/us-states/new-hampshire/imc-2009/definitions.md) | Any structure occupied or intended for supporting or sheltering any occupancy. |
| IPC 2009 | [Definitions](https://harth.build/resources/building-codes/us-states/new-hampshire/ipc-2009/definitions.md) | Any structure occupied or intended for supporting or sheltering any occupancy. |
| IECC 2009 | [Definitions](https://harth.build/resources/building-codes/us-states/maryland/iecc-2009/definitions.md) | Any structure used or intended for supporting or sheltering any use or occupancy. |

## Where building is used in the code

The term appears in 162 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next.

| Chapter | Code | Mentions |
| --- | --- | --- |
| [Fire Protection Systems](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/fire-protection-systems.md) | IFC 2009 | 622 |
| [Special Detailed Requirements Based on Use and Occupancy](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/special-detailed-requirements-based-on-use-and-occupancy.md) | IBC 2009 | 504 |
| [Fire Protection Systems](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/fire-protection-systems.md) | IBC 2009 | 474 |
| [Means of Egress](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/means-of-egress.md) | IFC 2009 | 398 |
| [Flammable and Combustible Liquids](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/flammable-and-combustible-liquids.md) | IFC 2009 | 341 |
| [General Building Heights and Areas](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/general-building-heights-and-areas.md) | IBC 2009 | 333 |
| [Building Planning](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/building-planning.md) | IRC 2009 | 327 |
| [Fire and Smoke Protection Features](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/fire-and-smoke-protection-features.md) | IBC 2009 | 326 |
| [Existing Structures](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/existing-structures.md) | IBC 2009 | 322 |
| [Means of Egress](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/means-of-egress.md) | IBC 2009 | 264 |
| [Structural Design](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/structural-design.md) | IBC 2009 | 235 |
| [Scope and Administration](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/scope-and-administration.md) | IRC 2009 | 228 |

_150 further chapters mention the term._

### The term in use

How the code actually writes about building, quoted from the 2009 text hosted here:

> Required systems shall be extended, altered or augmented as necessary to maintain and continue protection whenever the building is altered, remodeled or added to.

— [IFC 2009 §901.4](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/fire-protection-systems.md)

> Each coveredmall bUilding owner shall provide both the building and fire departments with a lease plan showing the location of each occupancy and its exits after the certificate of occupancy has been issued.

— [IBC 2009 §402.3](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/special-detailed-requirements-based-on-use-and-occupancy.md)

> No person shall remove or modify any fire protection system installed or maintained under the provisions of this code or the International Fire Code without approval by the building official.

— [IBC 2009 §901.3](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/fire-protection-systems.md)


## The terms building 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 building covers:

- **[Occupancy](https://harth.build/resources/glossary/occupancy.md)** — IMC 2009: The purpose for which a building, or portion thereof, is utilized or occupied.
- **[Structure](https://harth.build/resources/glossary/structure.md)** — IPC 2009: That which is built or constructed or a portion thereof.
- **[Dwelling](https://harth.build/resources/glossary/dwelling.md)** — IBC 2009: A building that contains one or two dwelling units used, intended or designed to be used, rented, leased, let or hired out to be occupied for living purposes.
- **[Shall](https://harth.build/resources/glossary/shall.md)** — IRC 2009: The term, when used in the code, is construed as mandatory.

## Building: what to open, and in what order

Every row is a document this term depends on. The [ICC code library](https://codes.iccsafe.org/codes) and the [ICC adoption maps](https://www.iccsafe.org/advocacy/code-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 | |
| Read the definition in the adopted IPC | Definitions | |
| Read the definition in the adopted IECC | Definitions | |
| Re-check the requirement that uses it | Fire Protection Systems (IFC 2009) | |
| Re-check the requirement that uses it | Special Detailed Requirements Based on Use and Occupancy (IBC 2009) | |
| Re-check the requirement that uses it | Fire Protection Systems (IBC 2009) | |
| Re-check the requirement that uses it | Means of Egress (IFC 2009) | |
| Confirm the dependent definition | Occupancy | |
| Confirm the dependent definition | Structure | |
| Confirm the dependent definition | Dwelling | |
| 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](https://harth.build/resources/glossary.md)
- [Structure: Building Code Definition](https://harth.build/resources/glossary/structure.md)
- [Occupancy: Building Code Definition](https://harth.build/resources/glossary/occupancy.md)
- [Dwelling: Building Code Definition](https://harth.build/resources/glossary/dwelling.md)

## 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](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.

### Source links

- [codes.iccsafe.org](https://codes.iccsafe.org/codes)

- [iccsafe.org](https://www.iccsafe.org/advocacy/code-adoption-maps/)

## Frequently asked questions

### What is the code definition of building?

The International Building Code (IBC) 2009 defines it in Definitions as: “Any structure used or intended for supporting or sheltering any use or occupancy.” 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 building the same way?

No. IBC 2009, IRC 2009, IFC 2009, IMC 2009, IPC 2009, IECC 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 building?

In this corpus the term is used across 162 chapters, led by Fire Protection Systems in the IFC 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 a building defined as?

In the 2009 I-Codes hosted here it is a defined term rather than a description. The IBC 2009 states, in Definitions: “Any structure used or intended for supporting or sheltering any use or occupancy.” It is defined in IBC 2009, IRC 2009, IFC 2009, IMC 2009, IPC 2009, IECC 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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