# Weatherproof: Building Code Definition > How the IRC 2009 define weatherproof, where the wording differs, and which chapters depend on the term. - Canonical: https://harth.build/resources/glossary/weatherproof/ - 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 | IRC 2009 (2009 editions transcribed in this corpus) | | Primary source | IRC 2009 Electrical Definitions (model text, not a jurisdiction's adopted text) | | Chapters using the term | 8 (counted across the codes hosted here) | | Wording identical across codes | Single code (compare before citing one code's wording under another) | ## Direct answer Weatherproof is a defined term in the International Residential Code (IRC) 2009, in Electrical Definitions. The code's own words are: “Constructed or protected so that exposure to the weather will not interfere with successful operation.” No other I-Code in this corpus defines it, so the IRC 2009 definition is the one to work from. The term is used in 8 chapters of this corpus, most often in Devices and Luminaires (IRC 2009), Duct Systems (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](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? **Weatherproof** — IRC 2009, Electrical Definitions: > Constructed or protected so that exposure to the weather will not interfere with successful operation. ![Labeled code-term definition diagram: Weatherproof: Building Code Definition](https://efwwel0vyt9vy5so.public.blob.vercel-storage.com/images/glossary/weatherproof/diagram-1344.webp) *How the IRC 2009 define weatherproof, where the wording differs, and which chapters depend on the term.* ## What must be verified before using this guidance? **Weatherproof** is defined once in this corpus, in the [Electrical Definitions](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/electrical-definitions.md) chapter of the International Residential Code (IRC) 2009: > Constructed or protected so that exposure to the weather will not interfere with successful operation. ## Where weatherproof is used in the code The term appears in 8 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next. | Chapter | Code | Mentions | | --- | --- | --- | | [Devices and Luminaires](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/devices-and-luminaires.md) | IRC 2009 | 8 | | [Duct Systems](https://harth.build/resources/building-codes/us-states/new-hampshire/imc-2009/duct-systems.md) | IMC 2009 | 2 | | [Exhaust Systems](https://harth.build/resources/building-codes/us-states/new-hampshire/imc-2009/exhaust-systems.md) | IMC 2009 | 2 | | [Fuel Oil Piping and Storage](https://harth.build/resources/building-codes/us-states/new-hampshire/imc-2009/fuel-oil-piping-and-storage.md) | IMC 2009 | 2 | | [Roof Assemblies and Rooftop Structures](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/roof-assemblies-and-rooftop-structures.md) | IBC 2009 | 1 | | [Electrical Definitions](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/electrical-definitions.md) | IRC 2009 | 1 | | [Power and Lighting Distribution](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/power-and-lighting-distribution.md) | IRC 2009 | 1 | | [Roof Assemblies](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/roof-assemblies.md) | IRC 2009 | 1 | ### The term in use How the code actually writes about weatherproof, quoted from the 2009 text hosted here: > A surface mounted switch or circuit breaker located in a damp or wet location or outside of a building shall be enclosed in a weatherproof enclosure or cabinet. — [IRC 2009 §E4001.7](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/devices-and-luminaires.md) > Insulated exterior ducts shall be protected with an approved weatherproof barrier. — [IMC 2009 §604.12](https://harth.build/resources/building-codes/us-states/new-hampshire/imc-2009/duct-systems.md) > An upblast fan shall be hinged and supplied with a flexible weatherproof electrical cable to permit inspection and cleaning. — [IMC 2009 §506.5.3](https://harth.build/resources/building-codes/us-states/new-hampshire/imc-2009/exhaust-systems.md) ## Weatherproof: 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 IRC | Electrical Definitions | | | Re-check the requirement that uses it | Devices and Luminaires (IRC 2009) | | | Re-check the requirement that uses it | Duct Systems (IMC 2009) | | | Re-check the requirement that uses it | Exhaust Systems (IMC 2009) | | | Re-check the requirement that uses it | Fuel Oil Piping and Storage (IMC 2009) | | | 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) - [Appliance: Building Code Definition](https://harth.build/resources/glossary/appliance.md) - [Plenum: Building Code Definition](https://harth.build/resources/glossary/plenum.md) - [Outlet: Building Code Definition](https://harth.build/resources/glossary/outlet.md) - [Bathroom: Building Code Definition](https://harth.build/resources/glossary/bathroom.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 weatherproof? The International Residential Code (IRC) 2009 defines it in Electrical Definitions as: “Constructed or protected so that exposure to the weather will not interfere with successful operation.” 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 weatherproof? In this corpus the term is used across 8 chapters, led by Devices and Luminaires 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 are the requirements for vapor barriers in the International 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 weatherproof, which the IRC 2009 defines as “Constructed or protected so that exposure to the weather will not interfere with successful operation.” — read both before applying either, and confirm the wording in the edition your jurisdiction has adopted. ### What does "weatherproof" mean? In the 2009 I-Codes hosted here it is a defined term rather than a description. The IRC 2009 states, in Electrical Definitions: “Constructed or protected so that exposure to the weather will not interfere with successful operation.” It is defined in IRC 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. --- - Continue in Harth (open this topic in the Harth agent): https://app.harth.build/agent?context=%2Fresources%2Fglossary%2Fweatherproof%2F - View this page in a browser: https://harth.build/resources/glossary/weatherproof/ - All resources for agents: https://harth.build/llms.txt