Building Code Glossary
Interior Finish: Building Code Definition
How the IBC 2009, IFC 2009 define interior finish, 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
Interior finish is a defined term in the International Building Code (IBC) 2009, in Interior Finishes. The code's own words are: “Interior finish includes interior wall and ceiling finish and interior floor finish.” The IFC 2009 carries the same definition word for word, so the term means the same thing in each. The term is used in 19 chapters of this corpus, most often in Interior Finishes (IBC 2009), Interior Finish, Decorative Materials and Furnishings (IFC 2009), Plastic (IBC 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?
Interior Finish — IBC 2009, Interior Finishes:
Interior finish includes interior wall and ceiling finish and interior floor finish.
What must be verified before using this guidance?
Two of the I-Codes in this corpus define Interior Finish, in identical words.
| Code | Where it is defined | Definition |
|---|---|---|
| IBC 2009 | Interior Finishes | Interior finish includes interior wall and ceiling finish and interior floor finish. |
| IFC 2009 | Definitions | Interior finish includes interior wall and ceiling finish and interior floor finish. |
Where interior finish is used in the code
The term appears in 19 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next.
| Chapter | Code | Mentions |
|---|---|---|
| Interior Finishes | IBC 2009 | 51 |
| Interior Finish, Decorative Materials and Furnishings | IFC 2009 | 38 |
| Plastic | IBC 2009 | 18 |
| Building Planning | IRC 2009 | 16 |
| Special Detailed Requirements Based on Use and Occupancy | IBC 2009 | 7 |
| Wall Construction | IRC 2009 | 7 |
| Construction Requirements for Existing Buildings | IFC 2009 | 6 |
| Definitions | IFC 2009 | 4 |
| Definitions | IBC 2009 | 3 |
| Fire and Smoke Protection Features | IBC 2009 | 3 |
| Plumbing Systems | IBC 2009 | 2 |
| Soils and Foundations | IBC 2009 | 2 |
7 further chapters mention the term.
The term in use
How the code actually writes about interior finish, quoted from the 2009 text hosted here:
Foam plastics shall not be used as interior finish except as provided in Section 803.4.
The provisions of this chapter shall govern interior finish, interior trim, furniture, furnishings, decorative materials and decorative vegetation in buildings.
Foam plastics that are used as interior finish on the basis of special tests shall also conform to the flame spread requirements of Chapter 8.
The terms interior finish is built out of
The definition above leans on 2 other defined terms. Each carries its own code definition, and a local amendment to any of them changes what interior finish covers:
- Interior Wall and Ceiling Finish — IBC 2009: The exposed interior surfaces of buildings, including but not limited to: fixed or movable walls and partitions; toilet room privacy partitions; columns; ceilings; and interior wainscoting, paneling or other finish applied structurally or for decoration, acoustical correction, surface insulation, structural …
- Interior Floor Finish — IBC 2009: The exposed floor surfaces of buildings including coverings applied over a finished floor or stair, including risers.
Interior Finish: 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 | Interior Finishes | |
| Read the definition in the adopted IFC | Definitions | |
| Re-check the requirement that uses it | Interior Finishes (IBC 2009) | |
| Re-check the requirement that uses it | Interior Finish, Decorative Materials and Furnishings (IFC 2009) | |
| Re-check the requirement that uses it | Plastic (IBC 2009) | |
| Re-check the requirement that uses it | Building Planning (IRC 2009) | |
| Confirm the dependent definition | Interior Wall and Ceiling Finish | |
| Confirm the dependent definition | Interior Floor Finish | |
| 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
- Interior Wall and Ceiling Finish: Building Code Definition
- Interior Floor Finish: 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 interior finish?
The International Building Code (IBC) 2009 defines it in Interior Finishes as: “Interior finish includes interior wall and ceiling finish and interior floor finish.” 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 interior finish?
In this corpus the term is used across 19 chapters, led by Interior Finishes 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 definition of interior finish?
In the 2009 I-Codes hosted here it is a defined term rather than a description. The IBC 2009 states, in Interior Finishes: “Interior finish includes interior wall and ceiling finish and interior floor finish.” 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.
Related pages
- Inspection Certificate: Building Code Definition
Inspection Certificate — IBC 2009 definition: An identification applied on a product by an approved agency containing the name of the manufacturer …
- Insulating Sheathing: Building Code Definition
Insulating Sheathing — IRC 2009 definition: An insulating board having a minimum thermal resistance of R-2 of the core material.
- Interceptor: Building Code Definition
Interceptor — IPC 2009 definition: A device designed and installed to separate and retain for removal, by automatic or manual means …
- Interior Floor Finish: Building Code Definition
Interior Floor Finish — IBC 2009 definition: The exposed floor surfaces of buildings including coverings applied over a finished floor or stair, including …
- Interior Floor-wall Base: Building Code Definition
Interior Floor-wall Base — IBC 2009 definition: Interior floor finish trim used to provide a functional and/or decorative border at the intersection of …
- Interior Surfaces: Building Code Definition
Interior Surfaces — IBC 2009 definition: Surfaces other than weather-exposed surfaces.