# Deep Foundation: Building Code Definition

> How the IBC 2009 define deep foundation, where the wording differs, and which chapters depend on the term.

- Canonical: https://harth.build/resources/glossary/deep-foundation/
- 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 | IBC 2009 (2009 editions transcribed in this corpus) |
| Primary source | IBC 2009 Soils and Foundations (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

Deep foundation is a defined term in the International Building Code (IBC) 2009, in Soils and Foundations. The code's own words are: “A deep foundation is a foundation element that does not satisfy the definition of a shallow foundation.” 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 3 chapters of this corpus, most often in Soils and Foundations (IBC 2009), Structural Tests and Special Inspections (IBC 2009), Definitions (IBC 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?

**Deep Foundation** — IBC 2009, Soils and Foundations:

> A deep foundation is a foundation element that does not satisfy the definition of a shallow foundation.

![Labeled code-term definition diagram: Deep Foundation: Building Code Definition](https://efwwel0vyt9vy5so.public.blob.vercel-storage.com/images/glossary/deep-foundation/diagram-1344.webp)

*How the IBC 2009 define deep foundation, where the wording differs, and which chapters depend on the term.*

## What must be verified before using this guidance?

**Deep Foundation** is defined once in this corpus, in the [Soils and Foundations](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/soils-and-foundations.md) chapter of the International Building Code (IBC) 2009:

> A deep foundation is a foundation element that does not satisfy the definition of a shallow foundation.

## Where deep foundation 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 |
| --- | --- | --- |
| [Soils and Foundations](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/soils-and-foundations.md) | IBC 2009 | 332 |
| [Structural Tests and Special Inspections](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/structural-tests-and-special-inspections.md) | IBC 2009 | 4 |
| [Definitions](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/definitions.md) | IBC 2009 | 1 |

### The term in use

How the code actually writes about deep foundation, quoted from the 2009 text hosted here:

> Where depositing concrete from the top of a deep foundation element, the concrete shall be chuted directly into smooth-sided pipes or tubes or placed in a rapid and continuous operation through a funnel hopper centered at the top of the element.

— [IBC 2009 §1808.8.3](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/soils-and-foundations.md)

> Special inspections shall be performed during installation and testing of driven deep foundation elements as required by Table 1704.8.

— [IBC 2009 §1704.8](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/structural-tests-and-special-inspections.md)


## The terms deep foundation 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 deep foundation covers:

- **[Shallow Foundation](https://harth.build/resources/glossary/shallow-foundation.md)** — IBC 2009: A shallow foundation is an individual or strip footing, a mat foundation, a slab-on-grade foundation or a similar foundation element.

## Deep Foundation: 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 IBC | Soils and Foundations | |
| Re-check the requirement that uses it | Soils and Foundations (IBC 2009) | |
| Re-check the requirement that uses it | Structural Tests and Special Inspections (IBC 2009) | |
| Re-check the requirement that uses it | Definitions (IBC 2009) | |
| Confirm the dependent definition | Shallow Foundation | |
| 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)
- [Shallow Foundation: Building Code Definition](https://harth.build/resources/glossary/shallow-foundation.md)
- [Helical Pile: Building Code Definition](https://harth.build/resources/glossary/helical-pile.md)
- [Building: Building Code Definition](https://harth.build/resources/glossary/building.md)
- [Construction Documents: Building Code Definition](https://harth.build/resources/glossary/construction-documents.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 deep foundation?

The International Building Code (IBC) 2009 defines it in Soils and Foundations as: “A deep foundation is a foundation element that does not satisfy the definition of a shallow foundation.” 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 deep foundation?

In this corpus the term is used across 3 chapters, led by Soils and Foundations 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 definition of a deep foundation?

In the 2009 I-Codes hosted here it is a defined term rather than a description. The IBC 2009 states, in Soils and Foundations: “A deep foundation is a foundation element that does not satisfy the definition of a shallow foundation.” 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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