Building Retaining Walls – solving unauthorised works problems

Unauthorised construction of retaining walls is a common challenge which the Corona Projects team of Town Planners help solve.

Many property owners mistakenly build retaining walls without realising they may need council approval to do so.

Unless the construction of a retaining wall meets specific criteria outlined for exempt development (no council approval necessary), it will require an approval by either a Complying Development Certificate (CDC) or a Development Application (DA) with local council.

When do I need council approval to build a retaining wall?

Retaining walls are only exempt if they meet certain criteria, which include but is not limited to:

• a setback of at least 1m from the property boundaries and
• a maximum height of 600mm from the natural ground level.

If construction has already commenced without obtaining the appropriate approvals, it is highly likely that a Building Information Certificate (BIC) will be required to legalise and regularise the works – in other words, to approve your works retrospectively.

What is a Building Information Certificate (BIC)?

A BIC provides formal acknowledgment from the local council that the existing unauthorised works are compliant with relevant building codes and regulations.

The process of obtaining a BIC may involve: submitting detailed documentation, including:

• engineering reports,
• structural certifications, and
• possibly requesting modifications to ensure the retaining wall meets the required safety and environmental standards.

If you don’t legalise these works you will be unable to sell your house later.

How do I get a Building Information Certificate (BIC) for my unauthorised retaining wall?

Your local council will assess the impact the wall may have on the your property, adjacent properties, and its overall structural integrity. They will consider the relevant Local Environmental Plan (LEP) and Development Control Plan (DCP) provisions as part of this process.

During the review, council may:

• request additional information to assist in their decision-making
• may propose modifications before granting approval
• may require a Development Application (DA) be submitted

For example: if the council determines that the retaining wall’s height could lead to adverse environmental impacts, they may request the wall be reduced in height, tiered, or that additional landscaping be provided for screening purposes.

If the retaining wall is structurally unstable, corrective works will need to be undertaken before a BIC can be issued.

Sometimes stormwater drainage has not been considered, but is required, which may trigger further works.

Finally, if the retaining wall encroaches onto council land, it is highly unlikely the council will approve the works.

The documents typically required to accompany a Building Information Certificate (BIC) for an unauthorised retaining wall include, but are not limited to:

• BIC Statement of Environmental Effects: Town Planner’s report which provides an assessment of the unauthorised works against the relevant council legislation and policies
• Architectural Plans: Detailed drawings prepared in a format that enables the council to clearly identify the unauthorized building works.
• Certificate of Structural Adequacy: A professional certification confirming that the retaining wall is structurally sound and safe for use.
• As-Built Stormwater Plans: Required if the retaining walls impact stormwater management on the site or involve the installation of agricultural drainage lines.
• Plumber’s Certificate: A certificate from a licensed plumber or the installer of the agricultural lines, verifying that the drainage system is legally compliant and functioning properly.
• Survey Plan: A current, comprehensive survey of the land, illustrating its present condition and the extent of any works undertaken.
• Building Identification Survey: Typically required when the retaining walls are constructed near property boundaries, this survey establishes the precise location of the works relative to the land’s legal boundaries.
• Owners consent: All registered owners of the land are required to provided their written consent for any BIC application. If your retaining wall extends onto your neighbour’s property, you will need to consult with them to obtain their written consent to submit with your application as well. If they are not willing to give their consent, you may need to remove any of the works which occurred over the boundary before proceeding with an application.

These documents help ensure compliance with local regulations and provide the necessary information for the council to assess the situation appropriately.

As you can imagine, a lot of work is involved here, so you should consider engaging an experienced Corona Projects Town Planner perform this work for you.

Get in touch with Corona Projects today.

Case Studies

Here are some examples of how Corona Projects has helped clients solve unauthroised build works for a retaining wall.

Stop order for unauthorised works on a retaining wall

John and Jane engaged a builder to undertake building works on their property, with a primary focus on reconstructing a dilapidated retaining wall. The builder assured them that all necessary approvals had been obtained prior to commencing the project, and the property owners, trusting his expertise, proceeded with the work. A majority of the new concrete retaining wall was constructed; however, the local council issued a stop work order, as there was no approvals for the work, and the builder abandoned the project. As a result, John and Jane were left in a challenging situation, with partially completed retaining walls scattered across their site.

Corona Projects stepped in to assist the clients, offering professional guidance and support. We prepared the necessary documentation for a Building Information Certificate (BIC) for the already-constructed works and a Development Application (DA) for the remaining construction required to finalise the project. This proactive approach helped the property owners navigate the complexities of the situation and move forward with the necessary approvals to bring the project to completion.

 

Demolition order for unauthorised works on retaining walls

Matthew was undertaking a rear yard remodelling project with the goal of creating a more functional landscaped area.

In the process, he exceeded the threshold for what is considered exempt development. Given the steep slope of the site, he introduced substantial new fill to create a more usable private open space for recreational purposes. To retain the fill, Matthew constructed sandstone block retaining walls. However, after the completion of the work, the council identified the unauthorised development and issued a demolition order.

The expert Corona Projects team helped Matthew resolve the issue with council. This included:

• preparing a Building Information Certificate (BIC) for the unauthorised works
• altering the retaining wall in order to better align with the natural ground level
• ensuring the demolition order was successfully removed

 

Unauthorised building works – discrepancy between works and approval

Kelly has engaged a builder to construct her dream home under the provisions of a Complying Development Certificate (CDC). However, as previously noted, the regulations governing the construction of retaining walls under the State Environmental Planning Policy (Exempt and Complying Development) 2008 for are quite restrictive.

Kelly’s builders proceeded with constructing retaining walls without securing the necessary approvals or ensuring that the works qualify for exempt development status.

When the certifier conducted their final inspection at Kelly’s property, they found discrepancies between the as-built works and the approved plans. This misalignment can prevented the issuance of an Occupation Certificate (OC), which is required to confirm the development’s compliance with building codes and safety standards. Without the OC, the development cannot be legally occupied!

The Corona Projects team were able to resolve these issues and to ensure Kelly received her OC allowing her to occupy the premises and protecting her ability to sell the property in the future.

 Request a free consultation with the Corona Projects team today!