# City Building Code Amendments

> Readable, source-linked guides to city amendments, adopted model-code editions, effective dates and authority contacts for architects.

- Canonical: https://harth.build/resources/building-codes/cities/
- Last updated: 2026-09-05

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## Direct answer and reference scope

City Building Code Amendments is a Harth adoption and amendment guide for United States. Readable, source-linked guides to city amendments, adopted model-code editions, effective dates and authority contacts for architects. Use the [International Code Council code library](https://codes.iccsafe.org/codes) to confirm the code edition currently adopted for the project, and compare the model text with state amendments, local amendments, effective dates and the permit authority's interpretation. The [ICC code library](https://codes.iccsafe.org/codes) is the model-code publication path. This Harth page summarizes adoption records and amendment sources; it does not reproduce the controlling code, provide a legal opinion or confirm which edition controls a particular address. Record the project jurisdiction, application date, occupancy, construction type and amendment set before relying on a section. Where this page conflicts with an official publication or the authority having jurisdiction, the official source controls.

_Authored and prepared by Harth from the linked agency records. Review scope: adoption status and source paths verified; project-specific applicability and local interpretation require AHJ confirmation._

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## Direct answer

A state’s adopted model code is not always the final rule for a project. Cities can adopt local amendments, administer separate energy or green codes, issue binding interpretations and set transition dates. These guides turn the official amendment documents into a project-start checklist while linking back to the controlling city publication.

| City | Current building-code baseline | Guide |
| --- | --- | --- |
| Austin, Texas | 2024 IBC; effective July 10, 2025 | [Austin amendments explained](https://harth.build/resources/building-codes/cities/austin-tx.md) |
| Denver, Colorado | 2025 Denver code based on 2024 I-Codes; effective Dec. 31, 2025 | [Denver amendments explained](https://harth.build/resources/building-codes/cities/denver-co.md) |
| Seattle, Washington | 2021 IBC with state and Seattle amendments | [Seattle amendments explained](https://harth.build/resources/building-codes/cities/seattle-wa.md) |

Each page separates adopted requirements from proposals and flags the other code layers that still need a project-specific check.

![Labeled code-chapter diagram: City Building Code Amendments](https://efwwel0vyt9vy5so.public.blob.vercel-storage.com/images/building-codes/cities/index/diagram-1344.webp)

*Readable, source-linked guides to city amendments, adopted model-code editions, effective dates and authority contacts for architects.*

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