Does changing internal walls require an amendment to the DA?

ACT Planning explains that an approved DA does not need to be amended where the proposed change would not need DA approval if it were carried out after the development was completed, subject to specific exceptions.

However, this does not mean every internal change can automatically be made. If the change is not DA-exempt or changes the development beyond what is covered by the existing approval, an amendment may be needed.

An essential design element is also relevant if an amendment is required. ACT Planning states that where an essential design element included by another entity needs to be changed, that entity will decide the amendment application. It does not say that changing an essential design element by itself automatically means an amendment is required.

Building Approval requirements should also be checked separately, particularly if structural walls or other building-code requirements are affected.

Reference: ACT Planning – Amend or appeal an application - https://www.planning.act.gov.au/applications-and-assessments/development-applications/amend-or-appeal-an-application