Building Code Glossary
Scupper: Building Code Definition
How the IBC 2009, IRC 2009 define scupper, 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
Scupper is a defined term in the International Building Code (IBC) 2009, in Roof Assemblies and Rooftop Structures. The code's own words are: “An opening in a wall or parapet that allows water to drain from a roof.” The IRC 2009 carries the same definition word for word, so the term means the same thing in each. The term is used in 6 chapters of this corpus, most often in Roof Assemblies and Rooftop Structures (IBC 2009), Storm Drainage (IPC 2009), Roof Assemblies (IRC 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?
Scupper — IBC 2009, Roof Assemblies and Rooftop Structures:
An opening in a wall or parapet that allows water to drain from a roof.
What must be verified before using this guidance?
Two of the I-Codes in this corpus define Scupper, in identical words.
| Code | Where it is defined | Definition |
|---|---|---|
| IBC 2009 | Roof Assemblies and Rooftop Structures | An opening in a wall or parapet that allows water to drain from a roof. |
| IRC 2009 | Definitions | An opening in a wall or parapet that allows water to drain from a roof. |
Where scupper is used in the code
The term appears in 6 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next.
| Chapter | Code | Mentions |
|---|---|---|
| Roof Assemblies and Rooftop Structures | IBC 2009 | 13 |
| Storm Drainage | IPC 2009 | 8 |
| Roof Assemblies | IRC 2009 | 6 |
| Definitions | IBC 2009 | 1 |
| Structural Design | IBC 2009 | 1 |
| Definitions | IRC 2009 | 1 |
The term in use
How the code actually writes about scupper, quoted from the 2009 text hosted here:
Parapet wall roof drainage scupper and overflow scupper location shall comply with the requirements of the International Building Code.
The scupper shall be located as determined by the roof slope and contributing roof area.
The terms scupper 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 scupper covers:
- Drain — IRC 2009: Any pipe that carries soil and water-borne wastes in a building drainage system.
Scupper: 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 | Roof Assemblies and Rooftop Structures | |
| Read the definition in the adopted IRC | Definitions | |
| Re-check the requirement that uses it | Roof Assemblies and Rooftop Structures (IBC 2009) | |
| Re-check the requirement that uses it | Storm Drainage (IPC 2009) | |
| Re-check the requirement that uses it | Roof Assemblies (IRC 2009) | |
| Re-check the requirement that uses it | Definitions (IBC 2009) | |
| Confirm the dependent definition | Drain | |
| 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
- Drain: Building Code Definition
- Aggregate: Building Code Definition
- Roof Assembly: Building Code Definition
- Roof Deck: 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 scupper?
The International Building Code (IBC) 2009 defines it in Roof Assemblies and Rooftop Structures as: “An opening in a wall or parapet that allows water to drain from a roof.” 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 scupper?
In this corpus the term is used across 6 chapters, led by Roof Assemblies and Rooftop Structures in the IBC 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 difference between a scupper and a drain?
In the 2009 I-Codes hosted here it is a defined term rather than a description. The IBC 2009 states, in Roof Assemblies and Rooftop Structures: “An opening in a wall or parapet that allows water to drain from a roof.” It is defined in IBC 2009, IRC 2009. It is not the same as Drain, which the IRC 2009 defines separately as “Any pipe that carries soil and water-borne wastes in a building drainage system.” 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 purpose of a scupper?
In the 2009 I-Codes hosted here it is a defined term rather than a description. The IBC 2009 states, in Roof Assemblies and Rooftop Structures: “An opening in a wall or parapet that allows water to drain from a roof.” It is defined in IBC 2009, 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.
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