Building Code Glossary
Clearance: Building Code Definition
How the IRC 2009, IMC 2009 define clearance, 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
Clearance is a defined term in the International Residential Code (IRC) 2009, in Fuel Gas. The code's own words are: “The minimum distance through air measured between the heat-producing surface of the mechanical appliance, device or equipment and the surface of the combustible material or assembly.” The IMC 2009 carries the same definition word for word, so the term means the same thing in each. The term is used in 70 chapters of this corpus, most often in Fuel Gas (IRC 2009), General Regulations (IMC 2009), Exhaust Systems (IMC 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?
Clearance — IRC 2009, Fuel Gas:
The minimum distance through air measured between the heat-producing surface of the mechanical appliance, device or equipment and the surface of the combustible material or assembly.
What must be verified before using this guidance?
Two of the I-Codes in this corpus define Clearance, in identical words.
| Code | Where it is defined | Definition |
|---|---|---|
| IRC 2009 | Fuel Gas | The minimum distance through air measured between the heat-producing surface of the mechanical appliance, device or equipment and the surface of the combustible material or assembly. |
| IMC 2009 | Definitions | The minimum distance through air measured between the heat-producing surface of the mechanical appliance, device or equipment and the surface of the combustible material or assembly. |
Where clearance is used in the code
The term appears in 70 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next.
| Chapter | Code | Mentions |
|---|---|---|
| Fuel Gas | IRC 2009 | 146 |
| General Regulations | IMC 2009 | 45 |
| Exhaust Systems | IMC 2009 | 36 |
| General Mechanical System Requirements | IRC 2009 | 35 |
| Services | IRC 2009 | 33 |
| Chimneys and Vents | IMC 2009 | 30 |
| Masonry | IBC 2009 | 28 |
| Scope and Administration | IFC 2009 | 20 |
| Chimneys and Vents | IRC 2009 | 17 |
| Building Services and Systems | IFC 2009 | 15 |
| Means of Egress | IBC 2009 | 14 |
| Building Planning | IRC 2009 | 13 |
58 further chapters mention the term.
The term in use
How the code actually writes about clearance, quoted from the 2009 text hosted here:
Appliances located in private garages shall be installed with a minimum clearance of 6 feet (1829 mm) above the floor.
Appliances located in private garages and carports shall be installed with a minimum clearance of 6 feet (1829 mm) above the floor.
Ducts shall have a minimum clearance of 6 inches (152 mm) to combustible materials.
The terms clearance is built out of
The definition above leans on 3 other defined terms. Each carries its own code definition, and a local amendment to any of them changes what clearance covers:
- Equipment — IRC 2009: All piping, ducts, vents, control devices and other components of systems other than appliances that are permanently installed and integrated to provide control of environmental conditions for buildings.
- Appliance — IRC 2009: Utilization equipment, normally built in standardized sizes or types, that is installed or connected as a unit to perform one or more functions such as clothes washing, air conditioning, food mixing, deep frying, etc.
- Device — IRC 2009: Aunit of an electrical system that carries or controls electrical energy as it principal function.
Clearance: 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 IRC | Fuel Gas | |
| Read the definition in the adopted IMC | Definitions | |
| Re-check the requirement that uses it | Fuel Gas (IRC 2009) | |
| Re-check the requirement that uses it | General Regulations (IMC 2009) | |
| Re-check the requirement that uses it | Exhaust Systems (IMC 2009) | |
| Re-check the requirement that uses it | General Mechanical System Requirements (IRC 2009) | |
| Confirm the dependent definition | Equipment | |
| Confirm the dependent definition | Appliance | |
| Confirm the dependent definition | Device | |
| 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
- Equipment: Building Code Definition
- Appliance: Building Code Definition
- Device: 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 clearance?
The International Residential Code (IRC) 2009 defines it in Fuel Gas as: “The minimum distance through air measured between the heat-producing surface of the mechanical appliance, device or equipment and the surface of the combustible material or assembly.” 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 clearance?
In this corpus the term is used across 70 chapters, led by Fuel Gas 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 is egress clearance?
In the 2009 I-Codes hosted here it is a defined term rather than a description. The IRC 2009 states, in Fuel Gas: “The minimum distance through air measured between the heat-producing surface of the mechanical appliance, device or equipment and the surface of the combustible material or assembly.” It is defined in IRC 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.
What is the minimum door clearance required by the California Building Code?
In the 2009 I-Codes hosted here it is a defined term rather than a description. The IRC 2009 states, in Fuel Gas: “The minimum distance through air measured between the heat-producing surface of the mechanical appliance, device or equipment and the surface of the combustible material or assembly.” It is defined in IRC 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.
What does IRC mean in building code?
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 clearance, which the IRC 2009 defines as “The minimum distance through air measured between the heat-producing surface of the mechanical appliance, device or equipment and the surface of the combustible material or assembly.” — read both before applying either, and confirm the wording in the edition your jurisdiction has adopted.
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