Updated 2026-09-07

Building Code Glossary

Combustible Fibers: Building Code Definition

How the IBC 2009, IFC 2009 define combustible fibers, where the wording differs, and which chapters depend on the term.

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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.

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Direct answer

Combustible fibers is a defined term in the International Building Code (IBC) 2009, in Use and Occupancy Classification. The code's own words are: “Readily ignitable and free-burning materials in a fibrous or shredded form, such as cocoa fiber, cloth, cotton, excelsior, hay, hemp, henequen, istle,jute, kapok, oakum, rags, sisal, Spanish moss, straw, tow, wastepaper, certain synthetic fibers or other like materials. This definition does not include densely packed baled cotton.” The IFC 2009 carries the same definition word for word, so the term means the same thing in each. The term is used in 12 chapters of this corpus, most often in Combustible Fibers (IFC 2009), Definitions (IFC 2009), Scope and Administration (IFC 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?

Combustible Fibers — IBC 2009, Use and Occupancy Classification:

Readily ignitable and free-burning materials in a fibrous or shredded form, such as cocoa fiber, cloth, cotton, excelsior, hay, hemp, henequen, istle,jute, kapok, oakum, rags, sisal, Spanish moss, straw, tow, wastepaper, certain synthetic fibers or other like materials. This definition does not include densely packed baled cotton.

Labeled code-term definition diagram: Combustible Fibers: Building Code Definition — How the IBC 2009, IFC 2009 define combustible fibers, where the wording differs, and which chapters depend on the term.

What must be verified before using this guidance?

Two of the I-Codes in this corpus define Combustible Fibers, in identical words.

Code	Where it is defined	Definition
IBC 2009	Use and Occupancy Classification	Readily ignitable and free-burning materials in a fibrous or shredded form, such as cocoa fiber, cloth, cotton, excelsior, hay, hemp, henequen, istle,jute, kapok, oakum, rags, sisal, Spanish moss, straw, tow, wastepaper, certain synthetic fibers or other like materials. This definition does not include densely packed baled cotton.
IFC 2009	Combustible Fibers	Readily ignitable and free-burning materials in a fibrous or shredded form, such as cocoa fiber, cloth, cotton, excelsior, hay, hemp, henequen, istle, jute, kapok, oakum, rags, sisal, Spanish moss, straw, tow, wastepaper, certain synthetic fibers or other like materials. This definition does not include densely packed baled cotton.

Where combustible fibers is used in the code

The term appears in 12 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next.

Chapter	Code	Mentions
Combustible Fibers	IFC 2009	22
Definitions	IFC 2009	4
Scope and Administration	IFC 2009	4
Exhaust Systems	IMC 2009	4
Use and Occupancy Classification	IBC 2009	3
Fire Protection Systems	IFC 2009	3
Fire Protection Systems	IBC 2009	2
Definitions	IBC 2009	1
High-piled Combustible Storage	IFC 2009	1
Definitions	IMC 2009	1
Definitions	IRC 2009	1
Fuel Gas	IRC 2009	1

The term in use

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

The equipment, processes and operations involving combustible fibers shall comply with this chapter.

— IFC 2009 §2901.1

An operational permit is required for the storage and handling of combustible fibers in quantities greater than 100 cubic feet (2.8 m3).

— IFC 2009 §105.6.7

Not less than a 3-foot (914 mm) clearance shall be maintained between automatic sprinklers and the top of piles of combustible fibers.

— IFC 2009 §903.3.3

The terms combustible fibers 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 combustible fibers covers:

Baled Cotton — IBC 2009: A natural seed fiber wrapped in and secured with industry accepted materials, usually consisting of burlap, woven polypropylene, polyethylene or cotton or sheet polyethylene, and secured with steel, synthetic or wire bands or wire; also includes linters (lint removed from …

Combustible Fibers: 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	Use and Occupancy Classification
Read the definition in the adopted IFC	Combustible Fibers
Re-check the requirement that uses it	Combustible Fibers (IFC 2009)
Re-check the requirement that uses it	Definitions (IFC 2009)
Re-check the requirement that uses it	Scope and Administration (IFC 2009)
Re-check the requirement that uses it	Exhaust Systems (IMC 2009)
Confirm the dependent definition	Baled Cotton
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.

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 combustible fibers?

The International Building Code (IBC) 2009 defines it in Use and Occupancy Classification as: “Readily ignitable and free-burning materials in a fibrous or shredded form, such as cocoa fiber, cloth, cotton, excelsior, hay, hemp, henequen, istle,jute, kapok, oakum, rags, sisal, Spanish moss, straw, tow, wastepaper, certain synthetic fibers or other like materials. This definition does not include densely packed baled cotton.” 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 combustible fibers?

In this corpus the term is used across 12 chapters, led by Combustible Fibers 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 considered a non-combustible building?

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 combustible fibers, which the IBC 2009 defines as “Readily ignitable and free-burning materials in a fibrous or shredded form, such as cocoa fiber, cloth, cotton, excelsior, hay, hemp, henequen, istle,jute, kapok, oakum, rags, sisal, Spanish moss, straw, tow, wastepaper, certain synthetic fibers or other like materials. This definition …” — read both before applying either, and confirm the wording in the edition your jurisdiction has adopted.

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