Building Code Glossary
Web: Building Code Definition
How the IBC 2009 define web, 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
Web is a defined term in the International Building Code (IBC) 2009, in Masonry. The code's own words are: “An interior solid portion of a hollow masonry unit as placed in masonry.” No other I-Code in this corpus defines it, so the IBC 2009 definition is the one to work from. The term is used in 17 chapters of this corpus, most often in Floors (IRC 2009), Wall Construction (IRC 2009), Roof-ceiling Construction (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?
Web — IBC 2009, Masonry:
An interior solid portion of a hollow masonry unit as placed in masonry.
What must be verified before using this guidance?
Web is defined once in this corpus, in the Masonry chapter of the International Building Code (IBC) 2009:
An interior solid portion of a hollow masonry unit as placed in masonry.
Where web is used in the code
The term appears in 17 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next.
| Chapter | Code | Mentions |
|---|---|---|
| Floors | IRC 2009 | 108 |
| Wall Construction | IRC 2009 | 100 |
| Roof-ceiling Construction | IRC 2009 | 93 |
| Soils and Foundations | IBC 2009 | 12 |
| Steel | IBC 2009 | 8 |
| Structural Design | IBC 2009 | 8 |
| General Regulations | IMC 2009 | 8 |
| Fire and Smoke Protection Features | IBC 2009 | 7 |
| Plumbing Fixtures | IRC 2009 | 6 |
| Definitions | IBC 2009 | 2 |
| Special Construction | IBC 2009 | 2 |
| Concrete | IBC 2009 | 1 |
5 further chapters mention the term.
The term in use
How the code actually writes about web, quoted from the 2009 text hosted here:
Web holes, web hole reinforcing, and web hole patching shall be in accordance with this section.
Web holes in gable endwall studs not conforming to the requirements of Section R603.2.5.1 shall be permitted to be reinforced if the hole is located fully within the center 40 percent of the span and the depth and length of the hole does not exceed 65 percent of the flat width of the web.
2.5.1 shall be permitted if the hole is located fully within the center 40 percent of the span and the depth and length of the hole does not exceed 65 percent of the flat width of the web.
Web compared with Shell
These two are the closest pair in the 2009 I-Codes: about 64 per cent of their defining words are the same. The code states both and compares neither, so the difference is worth naming.
| Wording unique to it | |
|---|---|
| Web (IBC 2009) | interior, solid |
| Shell (IBC 2009) | outer |
Everything else in the two definitions is shared. If a project turns on which of the two applies, those words are the whole of the test — and a local amendment that edits one of them without editing the other moves the boundary between web and shell.
The terms web 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 web covers:
- Masonry Unit — IBC 2009: Brick, tile, stone, glass block or concrete block conforming to the requirements specified in Section 2103.
- Masonry — IBC 2009: A built-up construction or combination of building units or materials of clay, shale, concrete, glass, gypsum, stone or other approved units bonded together with or without mortar or grout or other accepted methods of joining.
- Solid — IBC 2009: A material that has a melting point, decomposes or sublimes at a temperature greater than 68°F (20°C).
Web: 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 | Masonry | |
| Re-check the requirement that uses it | Floors (IRC 2009) | |
| Re-check the requirement that uses it | Wall Construction (IRC 2009) | |
| Re-check the requirement that uses it | Roof-ceiling Construction (IRC 2009) | |
| Re-check the requirement that uses it | Soils and Foundations (IBC 2009) | |
| Confirm the dependent definition | Masonry Unit | |
| Confirm the dependent definition | Masonry | |
| Confirm the dependent definition | Solid | |
| 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
- Masonry Unit: Building Code Definition
- Masonry: Building Code Definition
- Solid: 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 web?
The International Building Code (IBC) 2009 defines it in Masonry as: “An interior solid portion of a hollow masonry unit as placed in masonry.” 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 web?
In this corpus the term is used across 17 chapters, led by Floors 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 definition of a 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 web, which the IBC 2009 defines as “An interior solid portion of a hollow masonry unit as placed in masonry.” — read both before applying either, and confirm the wording in the edition your jurisdiction has adopted.
What does web mean?
In the 2009 I-Codes hosted here it is a defined term rather than a description. The IBC 2009 states, in Masonry: “An interior solid portion of a hollow masonry unit as placed in masonry.” It is defined in IBC 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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