One of the first questions we hear when discussing a retaining wall is: "Do we need council approval?" The answer depends on several factors, and it's important to get it right.
The Exempt Development Rule
NSW has an "exempt development" category that covers many residential retaining walls. Generally, a retaining wall can be built without development approval if it:
- Is less than 1 metre in height
- Is on your own property
- Isn't near a boundary in certain sensitive areas
- Doesn't hold back water for a dam or pond
- Doesn't support a building or major structure
Check with your local council. Exemption thresholds can vary by council area, and some councils have additional local conditions.
When You Probably Need Approval
- Wall is higher than 1 metre
- Wall is on or near a property boundary
- It's for a Torrens Title lot in certain areas
- The wall has structural complexity or engineering concerns
- It holds back water
How to Check Locally
Contact The Hills Shire Council, Hornsby Shire, or whichever council covers your property. They'll tell you:
- Whether your planned wall is exempt
- If not, what approval is required
- What documentation and fees apply
It's a 10-minute phone call and worth every second to avoid issues later.
Our Approach
When we quote a retaining wall project, we:
- Assess the site and height
- Ask where the wall sits relative to boundaries
- Advise whether council approval is likely required
- Can help you navigate the approval process if needed
For straightforward walls under 1 metre that are clearly exempt, we proceed without approvals. For anything bigger or more complex, we recommend confirming with council first.
Why Bother?
Skipping council approval on a wall that needs it can mean:
- Future compliance issues when selling your property
- Your neighbour asking questions
- Having to demolish and rebuild
- Fines or enforcement action
It's not worth the risk. The approval process is usually straightforward and adds a few weeks to your timeline.
The Bottom Line
Most residential retaining walls in the Hills District are exempt and can be built without approval. But always confirm with your council before you start. It takes one conversation and prevents problems down the track.
We're happy to help guide you through the process or refer you to engineers if a wall needs structural certification. That's part of the service.
