Does an existing approval on the property affect a new development proposal?
If there is an existing structure on the block that does not have the necessary approvals, it should be identified before preparing the new development application.
For example, an unapproved extension, garage, carport or other structure may take up space needed for the new development or affect requirements such as setbacks, site coverage, private open space, planting or parking.
It does not necessarily mean a new DA cannot proceed, but the unapproved structure may need to be dealt with separately or incorporated into the overall development strategy.
Reference: Building Act 2004 (ACT), current version — including s 69(2B); Certificate of completion of unsubstantiated building work – https://www.legislation.act.gov.au/View/a/2004-11/current/html/2004-11.html
Short Answer
Yes, it can. An existing unapproved structure may affect a new Development Application, particularly where it forms part of the area being redeveloped or affects the proposed development’s ability to meet current planning requirements.
The structure’s approval status should be established early so it can be determined whether it can remain, needs separate approval or certification, needs to be altered, or is proposed to be removed.
Detailed Explanation
An existing unapproved structure and a new DA involve related but distinct issues. A new Development Application should not be treated as automatically regularising or approving previous unauthorised building work.
For planning purposes, we would first establish the structure's status and determine whether it is being retained, altered or demolished as part of the proposal. If retained, its footprint and physical relationship to the proposed development may affect the site's ability to satisfy the current Territory Plan requirements.
There may also be a separate building approval/certification issue under the Building Act 2004. The current Building Act expressly provides a process associated with “unsubstantiated building work”, including a certificate-of-completion pathway under s 69(2B). The current approved form for that process is AF2025-19, effective from 19 September 2025.
Accordingly, where unapproved work is identified, we would normally establish its planning and building status before relying on that structure as part of the proposed development.
No minimum block size does not remove the need for planning assessment.
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