Building Code Glossary
Gypsum Board: Building Code Definition
How the IBC 2009, IFC 2009 define gypsum board, 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
Gypsum board is a defined term in the International Building Code (IBC) 2009, in Gypsum Board and Plaster. The code's own words are: “Gypsum wallboard, gypsum sheathing, gypsum base for gypsum veneer plaster, exterior gypsum soffit board, predecorated gypsum board or water-resistant gypsum backing board complying with the standards listed in Tables 2506.2, 2507.2 and Chapter 35.” The IFC 2009 defines 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 26 chapters of this corpus, most often in Gypsum Board and Plaster (IBC 2009), Wall Covering (IRC 2009), Wood (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?
Gypsum Board — IBC 2009, Gypsum Board and Plaster:
Gypsum wallboard, gypsum sheathing, gypsum base for gypsum veneer plaster, exterior gypsum soffit board, predecorated gypsum board or water-resistant gypsum backing board complying with the standards listed in Tables 2506.2, 2507.2 and Chapter 35.
What must be verified before using this guidance?
Two of the I-Codes in this corpus define Gypsum Board, and the wording is not identical — read the version that governs your question.
| Code | Where it is defined | Definition |
|---|---|---|
| IBC 2009 | Gypsum Board and Plaster | Gypsum wallboard, gypsum sheathing, gypsum base for gypsum veneer plaster, exterior gypsum soffit board, predecorated gypsum board or water-resistant gypsum backing board complying with the standards listed in Tables 2506.2, 2507.2 and Chapter 35. |
| IFC 2009 | Definitions | Gypsum wallboard, gypsum sheathing, gypsum base for gypsum veneer plaster, exterior gypsum soffit board, predecorated gypsum board or water-resistant gypsum backing board complying with the standards listed in Tables 2506.2 and 2507.2 and Chapter 35 of the International BUilding Code. |
Where gypsum board is used in the code
The term appears in 26 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next.
| Chapter | Code | Mentions |
|---|---|---|
| Gypsum Board and Plaster | IBC 2009 | 68 |
| Wall Covering | IRC 2009 | 44 |
| Wood | IBC 2009 | 28 |
| Building Planning | IRC 2009 | 21 |
| Wall Construction | IRC 2009 | 18 |
| Roof-ceiling Construction | IRC 2009 | 17 |
| Fire and Smoke Protection Features | IBC 2009 | 13 |
| Duct Systems | IMC 2009 | 12 |
| Scope and Administration | IBC 2009 | 11 |
| Special Detailed Requirements Based on Use and Occupancy | IBC 2009 | 6 |
| Fire Protection Systems | IFC 2009 | 6 |
| Definitions | IFC 2009 | 5 |
14 further chapters mention the term.
The term in use
How the code actually writes about gypsum board, quoted from the 2009 text hosted here:
Provisions of this chapter shall govern the materials, design, construction and quality of gypsum board, lath, gypsum plaster and cement plaster.
All gypsum board materials and accessories shall conform to ASTM C 36, C 79, C 475, C 514, C 630, C 931, C 960, C 1002, C 1047, C 1177, C 1178, C 1278, C 1395, C 1396 or C 1658 and shall be installed in accordance with the provisions of this section.
Gypsum board diaphragm ceilings shall be in accordance with Section 2508.5.
The terms gypsum board is built out of
The definition above leans on 5 other defined terms. Each carries its own code definition, and a local amendment to any of them changes what gypsum board covers:
- Gypsum Veneer Plaster — IBC 2009: Gypsum plaster applied to an approved base in one or more coats normally not exceeding ¼ inch (6.4 mm) in total thickness.
- Building — IBC 2009: Any structure used or intended for supporting or sheltering any use or occupancy.
- Backing — IBC 2009: The wall or surface to which the veneer is secured.
- Listed — IBC 2009: Equipment, materials, products or services included in a list published by an organization acceptable to the code official and concerned with evaluation of products or services that maintains periodic inspection of production of listed equipment or materials or periodic evaluation …
- Veneer — IBC 2009: A facing attached to a wall for the purpose of providing ornamentation, protection or insulation, but not counted as adding strength to the wall.
Gypsum Board: 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 | Gypsum Board and Plaster | |
| Read the definition in the adopted IFC | Definitions | |
| Re-check the requirement that uses it | Gypsum Board and Plaster (IBC 2009) | |
| Re-check the requirement that uses it | Wall Covering (IRC 2009) | |
| Re-check the requirement that uses it | Wood (IBC 2009) | |
| Re-check the requirement that uses it | Building Planning (IRC 2009) | |
| Confirm the dependent definition | Gypsum Veneer Plaster | |
| Confirm the dependent definition | Building | |
| Confirm the dependent definition | Backing | |
| 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
- Gypsum Veneer Plaster: Building Code Definition
- Building: Building Code Definition
- Backing: Building Code Definition
- Veneer: 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 gypsum board?
The International Building Code (IBC) 2009 defines it in Gypsum Board and Plaster as: “Gypsum wallboard, gypsum sheathing, gypsum base for gypsum veneer plaster, exterior gypsum soffit board, predecorated gypsum board or water-resistant gypsum backing board complying with the standards listed in Tables 2506.2, 2507.2 and Chapter 35.” 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 gypsum board?
In this corpus the term is used across 26 chapters, led by Gypsum Board and Plaster 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 IS code for gypsum plaster boards?
Gypsum Plaster is a separate defined term. The IBC 2009 defines it as: “A mixture of calcined gypsum or calcined gypsum and lime and aggregate and other approved materials as specified in this code.” That is not the same as gypsum board, which the IBC 2009 defines as “Gypsum wallboard, gypsum sheathing, gypsum base for gypsum veneer plaster, exterior gypsum soffit board, predecorated gypsum board or water-resistant gypsum backing board complying with the standards listed in Tables 2506.2, 2507.2 and Chapter 35.” — read both before applying either, and confirm the wording in the edition your jurisdiction has adopted.
What are the standard specifications for gypsum board?
In the 2009 I-Codes hosted here it is a defined term rather than a description. The IBC 2009 states, in Gypsum Board and Plaster: “Gypsum wallboard, gypsum sheathing, gypsum base for gypsum veneer plaster, exterior gypsum soffit board, predecorated gypsum board or water-resistant gypsum backing board complying with the standards listed in Tables 2506.2, 2507.2 and Chapter 35.” 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.
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