Retaining Wall Design
Concrete sleeper, sandstone, timber, reinforced blockwork and segmental retaining walls.
Retaining Wall Design
Our team specialises in designing retaining walls for both residential and commercial projects.
We deliver quick turnaround times, ensuring that retaining wall approvals and construction are completed efficiently, often ahead of the main house construction timeline. This proactive approach helps our clients avoid delays and keeps projects on schedule.
Our service areas include the Hunter Valley, Central Coast and Mid-North Coast, with projects spanning key locations such as Newcastle, Maitland, Thornton, Port Macquarie, Taree, Nambucca Heads, Coffs Harbour and Kempsey.
In addition to residential projects, we offer no-obligation quotes for a wide range of industrial and commercial retaining wall designs — providing tailored solutions to meet each project’s specific needs.
We're a part of all great back yards
At Dennis Partners, we work with clients, landscapers, and builders to select and design the best retaining wall solution for their spaces.
Let Dennis Partners create a practical, functional, and cost-effective design for your retaining wall project. As a guide, retaining wall design starts from $750. Final fees depend on the project, and a written fee proposal is provided before work begins.
Do you need help organising the design of your retaining wall?
If your project home builder has left you to organise the design and construction of the retaining wall then we are here to HELP
The benefits of our tool are clear
Retaining Wall Construction FAQ's
Can i build a retaining wall on my property boundary?
The retaining wall, including drainage behind it, must be located on your property unless you have the consent of the neighbour. We recommend allowing a minimum 300mm from the back of the wall to the boundary to allow for drainage.
Can i build my retaining wall over the sewer?
Most Council's allow building retaining walls over sewers provided the footing are outside the zone of influence (ZOI) and the retaining wall bridges the sewer where necessary.
What is the most common type of retaining wall?
The most common type of retaining wall used in residential construction is a concrete sleeper wall. The materials can be purchased from most hardware stores or from Outback Sleepers.
Do I need Council approval to build a retaining wall?
Some minor building renovations or works are classified as 'exempt development', which means they don’t need planning approval.
However, all exempt developments must still comply with the National Construction Code (NCC) and respect the property rights of adjacent owners, applicable common law, and other legislative requirements regarding approvals, licenses, permits, and authorities.
For retaining walls that do not require consent, the following conditions must be satisfied:
- Cuts or fills should be limited to 600mm of the existing ground level.
- They must be at least 1 meter away from lot boundaries.
- In heritage conservation areas, they should be located in the rear yard.
- At least 40 meters from natural water bodies is required.
- They must not change water flow or cause sediment transport to neighbouring properties.
- For retaining walls or structural supports:- They should not exceed 600mm in height.
- They must be separated by at least 2 meters from other structural supports.
- They must be 1 meter from easements, sewer, or water mains.
- Adequate drainage must connect to the stormwater system.
- If the fill exceeds 150mm, it should not cover more than 25% of the lot.
- Imported fill must be free of building waste and contain only virgin excavated natural material (VENM).
- In rural or environmental zones, fill should not exceed 100 cubic meters per lot.
The State Environmental Planning Policy (Exempt and Complying Development Codes) 2008 (known as the 'Codes SEPP') outlines additional requirements to fulfil exempt development criteria:
- Codes SEPP pt 2 div 1 sub-div 15 - Earthworks, retaining walls, and structural support.
You can visit the NSW Planning Portal for more information on exempt development.
If your proposal doesn’t meet the criteria for exempt development, you might consider applying through 'complying development' or a 'Development Application' (DA) for further options.
what is the advantage of concrete sleeper over timber sleeper retaining walls?
Concrete sleepers offer several advantages over timber sleepers in retaining walls:
1. Durability: Concrete is more resistant to weathering, rot, and pests compared to timber, leading to a longer lifespan.
2. Strength: Concrete sleepers can withstand greater loads and pressures, making them suitable for heavier soil and larger walls.
3. Maintenance: Concrete requires less maintenance over time, whereas timber may need regular treatments or replacements due to decay or insect damage.
4. Aesthetic Options: Concrete sleepers can be manufactured in various designs, colors, and textures, providing more aesthetic flexibility.
5. Fire Resistance: Concrete is non-combustible, offering better fire resistance compared to timber.
6. Environmental Impact: While timber is a renewable resource, the sourcing of sustainable timber can be challenging. Concrete can be made from recycled materials, thus potentially reducing its environmental footprint.
7. Installation: Concrete sleepers can often be installed faster and require less labor than traditional timber options, especially in larger projects.
These factors make concrete sleepers a popular choice for many retaining wall applications.
What are the Complying Development requirements for retaining walls?
When using the complying development building approval pathway, you must adhere to all applicable rules and clauses. If you fail to meet any specific clause, complying development cannot proceed.
For retaining wall complying development approval, review the clauses listed below and ensure that the architectural plans and all other documentation comply with the following clauses:
The NSW legislation for complyig development retaining walls - clause 3.30.
Retaining Wall Useful Planning information
About Us
Established in 1974 Dennis Partners have been providing engineering services throughout Australia and Papua New Guinea.
Dennis Partners’ engineering firm specializes in the provision of Civil and Structural engineering services in major regional centers such as Newcastle, Taree, Port Macquarie, Kempsey and Coffs Harbour.