# Low-voltage Lighting: Building Code Definition > How the IECC 2009 define low-voltage lighting, where the wording differs, and which chapters depend on the term. - Canonical: https://harth.build/resources/glossary/low-voltage-lighting/ - 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 | IECC 2009 (2009 editions transcribed in this corpus) | | Primary source | IECC 2009 Definitions (model text, not a jurisdiction's adopted text) | | Chapters using the term | 3 (counted across the codes hosted here) | | Wording identical across codes | Single code (compare before citing one code's wording under another) | ## Direct answer Low-voltage lighting is a defined term in the International Energy Conservation Code (IECC) 2009, in Definitions. The code's own words are: “Lighting equipment powered through a transformer such as a cable conductor, a rail conductor and track lighting.” No other I-Code in this corpus defines it, so the IECC 2009 definition is the one to work from. The term is used in 3 chapters of this corpus, most often in Swimming Pools (IRC 2009), Commercial Energy Efficiency (IECC 2009), Definitions (IECC 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? **Low-voltage Lighting** — IECC 2009, Definitions: > Lighting equipment powered through a transformer such as a cable conductor, a rail conductor and track lighting. ![Labeled code-term definition diagram: Low-voltage Lighting: Building Code Definition](https://efwwel0vyt9vy5so.public.blob.vercel-storage.com/images/glossary/low-voltage-lighting/diagram-1344.webp) *How the IECC 2009 define low-voltage lighting, where the wording differs, and which chapters depend on the term.* ## What must be verified before using this guidance? **Low-voltage Lighting** is defined once in this corpus, in the [Definitions](https://harth.build/resources/building-codes/us-states/maryland/iecc-2009/definitions.md) chapter of the International Energy Conservation Code (IECC) 2009: > Lighting equipment powered through a transformer such as a cable conductor, a rail conductor and track lighting. ## Where low-voltage lighting is used in the code The term appears in 3 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next. | Chapter | Code | Mentions | | --- | --- | --- | | [Swimming Pools](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/swimming-pools.md) | IRC 2009 | 5 | | [Commercial Energy Efficiency](https://harth.build/resources/building-codes/us-states/maryland/iecc-2009/commercial-energy-efficiency.md) | IECC 2009 | 1 | | [Definitions](https://harth.build/resources/building-codes/us-states/maryland/iecc-2009/definitions.md) | IECC 2009 | 1 | ### The term in use How the code actually writes about low-voltage lighting, quoted from the 2009 text hosted here: > Where a nonmetallic conduit is installed between a forming shell and a junction box, transformer enclosure, or other enclosure, a 8 AWG insulated copper bonding jumper shall be installed in this conduit except where a listed low-voltage lighting system not requiring grounding is used. — [IRC 2009 §E4205.3](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/swimming-pools.md) ## The terms low-voltage lighting 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 low-voltage lighting covers: - **[Equipment](https://harth.build/resources/glossary/equipment.md)** — 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. - **[Conductor](https://harth.build/resources/glossary/conductor.md)** — IPC 2009: A pipe inside the building that conveys storm water from the roof to a storm or combined bUilding drain. ## Low-voltage Lighting: 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 IECC | Definitions | | | Re-check the requirement that uses it | Swimming Pools (IRC 2009) | | | Re-check the requirement that uses it | Commercial Energy Efficiency (IECC 2009) | | | Re-check the requirement that uses it | Definitions (IECC 2009) | | | Confirm the dependent definition | Equipment | | | Confirm the dependent definition | Conductor | | | 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) - [Equipment: Building Code Definition](https://harth.build/resources/glossary/equipment.md) - [Conductor: Building Code Definition](https://harth.build/resources/glossary/conductor.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 low-voltage lighting? The International Energy Conservation Code (IECC) 2009 defines it in Definitions as: “Lighting equipment powered through a transformer such as a cable conductor, a rail conductor and track lighting.” 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 low-voltage lighting? In this corpus the term is used across 3 chapters, led by Swimming Pools 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 the NEC code for low-voltage lighting systems? In the 2009 I-Codes hosted here it is a defined term rather than a description. The IECC 2009 states, in Definitions: “Lighting equipment powered through a transformer such as a cable conductor, a rail conductor and track lighting.” It is defined in IECC 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%2Flow-voltage-lighting%2F - View this page in a browser: https://harth.build/resources/glossary/low-voltage-lighting/ - All resources for agents: https://harth.build/llms.txt