Quick answer: low walls (generally up to 600mm) that meet all the NSW exempt development conditions usually don't need approval. Taller walls, walls on or near a boundary, and walls that support a driveway, building or pool usually need a Complying Development Certificate or DA — and an engineer's design. Rules change and every property is different, so we check your address before we quote.
The three approval pathways in NSW
1. Exempt development — no approval needed
The NSW State Environmental Planning Policy (Exempt and Complying Development Codes) 2008 lets some minor works go ahead without approval if they meet every condition. For retaining walls and earthworks, the conditions generally cover things like:
- a maximum height (generally 600mm) of cut or fill;
- distance from property boundaries;
- proper drainage that doesn't redirect water onto neighbours;
- not being on a heritage item, in certain environmentally sensitive or foreshore areas, or on land with other restrictions.
If any condition isn't met, the wall isn't exempt. Always check the current codes on the NSW Planning Portal or ask a certifier.
2. Complying Development Certificate (CDC)
A fast-track approval issued by a private certifier or council when the wall meets set standards. It's common for retaining walls built as part of a new house, pool or granny flat, and usually needs engineering drawings.
3. Development Application (DA)
Where the wall doesn't fit the exempt or complying rules — for example a taller wall, a heritage area, a foreshore site or a landslip zone — a DA is lodged with council, usually with engineering plans and sometimes a geotechnical report.
When you'll need an engineer
Regardless of approval, you should expect engineering when a wall is over about 1m, supports a driveway, pool, building or slope, is terraced, or sits on or near a boundary. See engineered retaining walls.
Boundary walls and neighbours
- The whole wall — footings included — should sit on your side of the boundary unless you have a written agreement.
- Drainage must not discharge onto the neighbour's property.
- The NSW Dividing Fences Act covers fences, not retaining walls — so a fence on top of a wall and the wall itself are treated differently.
- As a general rule, the owner whose land was cut or filled to create the level difference is usually responsible for the wall. Every case depends on its history, so get advice for disputes.
Other things councils look at
- Heritage conservation areas — common in the Inner West, Paddington/Woollahra and Hunters Hill.
- Foreshore building lines — waterfront land on the harbour, Georges River and Port Hacking.
- Landslip / geotechnical zones — parts of the Northern Beaches and North Shore.
- Bushfire-prone land — affects materials near the house.
- Tree protection — walls near significant trees may need an arborist and approval.
- Easements and services — we lodge a Before You Dig Australia (BYDA) request before excavating.
How we handle it
- At the site visit we check height, location, loads and your property's planning controls.
- We tell you which pathway applies and what it costs — in the quote.
- We coordinate the engineer and certifier/council, and build exactly to the approved design.
This guide is general information only, not legal or planning advice. Always confirm the current requirements for your property with your council or an accredited certifier.
Approval FAQs
Can I build a retaining wall without council approval in NSW?
Often, yes, for low walls. Under the NSW exempt development rules, low retaining walls (generally up to 600mm) that meet all the conditions — such as distance from boundaries, drainage and not being on heritage or certain other land — may not need approval. Always check the current rules for your property.
What height retaining wall needs approval in NSW?
As a general guide, walls over about 600mm, or walls that don't meet every exempt condition, need approval through a Complying Development Certificate or a Development Application. Walls over about 1m almost always need engineering.
Who is responsible for a retaining wall between neighbours?
As a general rule in NSW, the owner whose land was cut or filled to create the difference in levels is usually responsible. The history of the site matters, so get legal advice for disputes.
Do you organise approvals?
Yes. We check your property's planning controls, coordinate the engineer and certifier, and build to the approved plans.