# Storefront: Building Code Definition > How the IECC 2009 define storefront, where the wording differs, and which chapters depend on the term. - Canonical: https://harth.build/resources/glossary/storefront/ - 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 | 4 (counted across the codes hosted here) | | Wording identical across codes | Single code (compare before citing one code's wording under another) | ## Direct answer Storefront is a defined term in the International Energy Conservation Code (IECC) 2009, in Definitions. The code's own words are: “A nonresidential system of doors and windows mulled as a composite fenestration structure that has been designed to resist heavy use. Storefrontsystems include, but are not limited to, exterior fenestration systems that span from the floor level or above to the ceiling of the same story on commercial buildings.” 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 4 chapters of this corpus, most often in Commercial Energy Efficiency (IECC 2009), Definitions (IECC 2009), Glass and Glazing (IBC 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](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? **Storefront** — IECC 2009, Definitions: > A nonresidential system of doors and windows mulled as a composite fenestration structure that has been designed to resist heavy use. Storefrontsystems include, but are not limited to, exterior fenestration systems that span from the floor level or above to the ceiling of the same story on commercial buildings. ![Labeled code-term definition diagram: Storefront: Building Code Definition](https://efwwel0vyt9vy5so.public.blob.vercel-storage.com/images/glossary/storefront/diagram-1344.webp) *How the IECC 2009 define storefront, where the wording differs, and which chapters depend on the term.* ## What must be verified before using this guidance? **Storefront** 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: > A nonresidential system of doors and windows mulled as a composite fenestration structure that has been designed to resist heavy use. Storefrontsystems include, but are not limited to, exterior fenestration systems that span from the floor level or above to the ceiling of the same story on commercial buildings. ## Where storefront is used in the code The term appears in 4 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next. | Chapter | Code | Mentions | | --- | --- | --- | | [Commercial Energy Efficiency](https://harth.build/resources/building-codes/us-states/maryland/iecc-2009/commercial-energy-efficiency.md) | IECC 2009 | 6 | | [Definitions](https://harth.build/resources/building-codes/us-states/maryland/iecc-2009/definitions.md) | IECC 2009 | 2 | | [Glass and Glazing](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/glass-and-glazing.md) | IBC 2009 | 1 | | [Special Detailed Requirements Based on Use and Occupancy](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/special-detailed-requirements-based-on-use-and-occupancy.md) | IBC 2009 | 1 | ### The term in use How the code actually writes about storefront, quoted from the 2009 text hosted here: > Curtain wall, storefront glazing and commercial-glazed swinging entrance doors and revolving doors shall be tested for air leakage at 1.57 pounds per square foot (psf) (75 Pa) in accordance with ASTM E 283. — [IECC 2009 §502.4.2](https://harth.build/resources/building-codes/us-states/maryland/iecc-2009/commercial-energy-efficiency.md) > Plastic signs affixed to the storefront of any tenant space facing the mall shall be limited as specified in Sections 402.16.1 through 402.16.5.2. — [IBC 2009 §402.16](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/special-detailed-requirements-based-on-use-and-occupancy.md) ## The terms storefront is built out of The definition above leans on 4 other defined terms. Each carries its own code definition, and a local amendment to any of them changes what storefront covers: - **[Fenestration](https://harth.build/resources/glossary/fenestration.md)** — IRC 2009: Skylights, roof windows, vertical windows (whether fixed or moveable); opaque doors; glazed doors; glass block; and combination opaque/glazed doors. - **[Structure](https://harth.build/resources/glossary/structure.md)** — IPC 2009: That which is built or constructed or a portion thereof. - **[System](https://harth.build/resources/glossary/system.md)** — IFC 2009: An assembly of equipment consisting of a tank, container or containers, appurtenances, pumps, compressors and connecting piping. - **[Story](https://harth.build/resources/glossary/story.md)** — IBC 2009: That portion ofa building included between the upper surface of a floor and the upper surface of the floor or roof next above (also see "Basement," "Mezzanine" and Section 502.1). ## Storefront: 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 | Commercial Energy Efficiency (IECC 2009) | | | Re-check the requirement that uses it | Definitions (IECC 2009) | | | Re-check the requirement that uses it | Glass and Glazing (IBC 2009) | | | Re-check the requirement that uses it | Special Detailed Requirements Based on Use and Occupancy (IBC 2009) | | | Confirm the dependent definition | Fenestration | | | Confirm the dependent definition | Structure | | | Confirm the dependent definition | System | | | 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) - [Fenestration: Building Code Definition](https://harth.build/resources/glossary/fenestration.md) - [Structure: Building Code Definition](https://harth.build/resources/glossary/structure.md) - [System: Building Code Definition](https://harth.build/resources/glossary/system.md) - [Story: Building Code Definition](https://harth.build/resources/glossary/story.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 storefront? The International Energy Conservation Code (IECC) 2009 defines it in Definitions as: “A nonresidential system of doors and windows mulled as a composite fenestration structure that has been designed to resist heavy use. Storefrontsystems include, but are not limited to, exterior fenestration systems that span from the floor level or above to the ceiling of the same story on commercial buildings.” 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 storefront? In this corpus the term is used across 4 chapters, led by Commercial Energy Efficiency in the IECC 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 a storefront in construction? In the 2009 I-Codes hosted here it is a defined term rather than a description. The IECC 2009 states, in Definitions: “A nonresidential system of doors and windows mulled as a composite fenestration structure that has been designed to resist heavy use. Storefrontsystems include, but are not limited to, exterior fenestration systems that span from the floor level or above to the ceiling of the same story on commercial buildings.” 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%2Fstorefront%2F - View this page in a browser: https://harth.build/resources/glossary/storefront/ - All resources for agents: https://harth.build/llms.txt