Before starting any retaining wall or site works project, there are specific approvals you'll need to secure. Find out about requirements and how to apply.
Definitions
- Retaining wall: A retaining wall is a structure specifically designed to support soil on a slope that is steeper than the natural inclination of the land, preventing subsidence. Such walls become necessary in areas where the land's differing levels require support at angles beyond its natural capacity to sustain itself.
- Development (Planning) Approval: This is the City’s approval of your project's design and location, ensuring it aligns with local zoning and planning rules. It's the essential first step for any new building or significant alteration on your property.
- Building Permit: A formal permission from the City for the construction, extension, or major renovation of a building, ensuring safety and compliance with building codes.
- R-Codes: R-Codes, formally known as State Planning Policy 7.3 - Residential Design Codes, are a set of regulations that govern residential development in Western Australia. They detail the minimum requirements for the design and assessment of residential properties, focussing on aspects like building size, open space, setbacks, and density to ensure sustainable and community-friendly development across various residential zones.
Responsibility for constructing a retaining wall
Responsibility for constructing a retaining wall falls to the party altering the land's natural slope, whether by excavation (cutting) or by adding to it (filling). In situations where both neighbours have modified the land's elevation, each is responsible for the construction and upkeep of the retaining wall proportional to their alterations.
It's important to note that a dividing fence does not qualify to retain soil.
Find out if you need planning approval and/or a building permit below and how to apply.
How to apply
Retaining walls and site works on residential properties require a development (planning) application unless they comply with the Residential Design Codes (R-Codes), the City’s Residential Development Local Planning Policy, the Development in Housing Opportunity Areas Local Planning Policy (HOALPP), or an applicable structure plan.
Single houses or grouped dwellings
Development (Planning) Approval is not required if your retaining walls and site works meet the following criteria:
- Retaining, fill, or excavation between the street boundary and setback does not exceed maximum heights per your R-Code density.
- Retaining and fill behind the street setback meet specified height and setback requirements.
- There are no restrictions on excavation and associated retaining behind the street setback.
Additional requirements that may apply include:
- Screening privacy: If retaining and fill exceeding 0.5m are within 7.5m of a side or rear boundary without existing screening, additional measures are required. Screening should be 1.6m above the finished ground level, made of durable material, and permanently affixed to prevent overlooking into neighbouring properties.
- Street walls or fences: Refer to Fencing and Street Walls page.
- Structure Plan areas: Properties within a structure plan area may be subject to further requirements.
Not sure of your R-Code or if your property is in a structure plan area? Insert your address into our online mapping system to view the R-Code and structure plan details. Contact the City of you need assistance.
Table 1: Retaining wall setback requirements based on R-Code density
Please note: For dual-density codes, if the property is not developed to the higher density, adhere to the R20 setback requirements.
| R-Code Density | Street Setback | Maximum Height of Retaining Walls, Excavation and/or Fill in the Street Setback |
|---|---|---|
| R20 | Street the house faces: 6m, or the setback between the street and house whichever is the lesser. Other streets (corner property): 1.5m |
1m Any retaining and fill within 1.5m of where a driveway meets the street boundary shall be a maximum height of 0.75m. |
| R20/25 | Street the house faces: 4m Other streets (corner property): 2m |
0.5m |
| R20/30 | Street the house faces: 4m Other streets (corner property): 2m |
0.5m |
| R20/40 | Street the house faces: 4m Other streets (corner property): 2m |
0.5m |
| R20/60 | Street the house faces: 2m Other streets (corner property): 2m |
0.5m |
Table 2: Height from Natural Ground Level – 3m+
| Height from Natural Ground Level | Minimum Setback to a Property Boundary |
|---|---|
| 0.5m or less | 0m |
| 1m | 1m |
| 1.5m | 1.5m |
| 2m | 2m |
| 2.5m | 2.5m |
| 3m | 3m |
If your project does not comply with the requirements set out in Step 1 above, you will need to apply for Development (Planning) Approval. This requires submitting an application form, along with building plans and a cover letter. Application fees will apply.
For detailed information, refer to the Development (Planning) Approval Applications.
A building permit is not required for a retaining wall if it meets all the following criteria:
- The wall does not exceed a height of 0.5m
- It is not part of, nor does it require, additional building work for the protection of adjoining land
- It does not adversely affect neighbouring properties in a way that would necessitate their consent.
You have two options when applying for a Building Permit:
- Certified application: Lodge a BA1 form, accompanied by a Certificate of Design Compliance (BA3 form) signed by a registered building surveyor, confirming compliance with building standards.
- Uncertified application: Lodge a BA2 form, accompanied with the Uncertified Building Application Checklist - Retaining Walls (PDF). The City will internally arrange approval of building standards.
You can download BA1 and BA2 forms from the Department of Energy Mines Industry Regulation and Safety website.
For more detailed information, including the application form, checklist, assessment process, and fees can be found on the Requirements for Building Applications page.
Guidelines for building and maintaining retaining walls
Location of retaining walls
Retaining walls should ideally be constructed within the property boundaries where the works are proposed. Construction across property boundaries is permitted only with written agreement from all affected neighbours.
In instances where a retaining wall extends beyond the property boundary, a Notice and request for consent to encroach or adversely affect (BA20 form) is required. This form must accompany the building permit application. Additionally, Planning (Development) Application forms, where applicable, must be signed by both landowners involved.
Positioning of dividing fences near retaining walls
A dividing fence is to be positioned on the higher ground of a retaining wall which abuts a common boundary.
Privacy and overlooking
To safeguard privacy and prevent overlooking into adjoining properties, a fence measuring 1.8 metres in height is permitted atop a retaining wall. This applies when the wall:
- Exceeds 0.5m in height
- Is situated outside the front setback area of a property.
- For fencing within the front setback area, adherence to the R-Codes' requirements for front fencing is mandatory. For more information refer to Fences and Street Walls.
Maintaining retaining walls
Owners are responsible for ensuring their retaining walls remain structurally sound. Should the City deem a retaining wall structurally inadequate, the owner must engage a practising structural engineer to assess the situation. Based on this assessment, the engineer will determine the necessary actions, if any, to restore the wall's structural integrity. The cost of consulting a structural engineer falls solely on the owner.
Retaining wall disputes
When facing issues or disputes related to retaining walls, it's best to first talk with the other party involved. A constructive conversation can often find a mutual solution. These guidelines aim to help navigate retaining wall disputes smoothly.
Steps to resolving disputes
- What to do: Check the ground levels on both sides of the boundary.
- How to do it: It's wise to hire a Licensed Land Surveyor to conduct a ‘Contour and Feature Survey’ to accurately map out the current land levels.
- Original vs. current: Match up the original ground levels (from before any construction) with the newly surveyed levels. You may find the original levels on the Building Approval Site Plan. (Find out how to request copies of building plans.)
- Identify changes: Note any changes in land height, whether it's been raised or lowered.
- Goal: Aim for a solution that everyone agrees on.
- Agreement points:
- Decide whether to return the ground to its original level or install a retaining system.
- Agree on the retaining wall’s location relative to the boundary.
- Schedule when the wall will be constructed.
- Determine who will build the wall.
- Split the costs fairly between parties.
- Decide who will apply for the necessary Building Permit.
Refer to requirements above.
When land alterations impact dividing fences
If changes to the natural ground level near a boundary adversely affect a dividing fence, the owner who made the alterations is usually responsible. This responsibility might include repairing or replacing the fence, potentially leading to civil action under the Dividing Fences Act 1961.
- Raised land: If land is raised above its natural level, the owner must ensure soil or materials don't spill onto the adjacent, lower property.
- Lowered land: When land is excavated below its natural level, it's up to that landowner to manage any changes that could affect the stability of neighbouring land.
Mediation for unresolved disputes
Sometimes, despite best efforts, disputes remain unresolved. In such cases, mediation offers a path forward. Mediation is a way to resolve disputes with the help of neutral, independent mediators. It allows all parties to discuss their issues and find a mutually agreeable solution.
The initial point of contact for mediation is the City’s Customer Relations Advocate. This process is coordinated and conducted by the Citizens Advice Bureau (CAB), under the guidance of two experienced and professionally qualified mediators.
For more details on mediation, please contact the City’s Customer Relations Advocate at 9400 4000. Alternatively, you may consider seeking legal advice on the matter.
More information and contact
For more information on approval and permit requirements for retaining walls, contact the City on 9400 4000 or email info@joondalup.wa.gov.au. You can also visit the City’s Customer Care desk during office hours Monday - Friday, 8.30am - 5pm.