The Not-So-Bright Side of Unauthorised Sunrooms and House Extensions
April 12, 2025by coronaprojects..Blog
Completing a house extension or enclosing your existing balcony into a sunroom can be a great idea to maximise your floor area and add the extra room you have always wanted.
This type of building works usually need a Development Application (DA) or a Complying Development Certificate (CDC) and if you don’t make sure you have these necessary approvals, you could end up with an ‘unauthorised works situation’!
What happens if I have unauthorised building works?
Generally, once your local Council has identified unauthorised building works on your property, they will request the space to be reverted to its previous state.
In order to keep these works as they are, you will be required to submit and successfully obtain a Building Information Certificate (BIC) application.
Common problems that result in unauthorised sunrooms or house extensions include:
- Exceeding the maximum floor area permitted for your site.
- Non-compliance with the Council development standards.
- Key compliance issues with the Building Code of Australia (BCA).
- Structural inadequacy of the structure and/or extension.
- Non-compliance with councils heritage controls – If located within a building of heritage significance or a heritage conservation area.
Corona Projects helping their clients with unauthorised building works
Case Study 1: Conversion of an Existing Balcony into a Sunroom
John recently purchased a new two-storey dwelling with a large first floor balcony facing the street frontage. Once John had moved in, he decided to convert the balcony into a sunroom to create an additional living space. This was done by enclosing the open three sides with a combination of walls and windows.
This type of building work is not considered exempt development because it does not fall under Minor Building Alterations (Internal or External)1.
Like many new home owners, John did not realise any formal approval was required for the works to be carried out.
John is now facing an order from his local Council to restore the balcony to its previously approved state. He sought advice from a Corona Projects Town Planner, who helped him determine if the newly created living space has increased the floor space ratio of the building beyond the maximum permitted for his site under the Council’s Local Environmental Plan (LEP).
It is common for new dwellings or dual occupancies to be built to the maximum allowable floor space. Without knowledge of the relevant FSR standards, it is possible that our clients can unknowingly exceeded the maximum floor space permitted for his property.
This is one of the most common issues related to newly enclosed sunrooms and house extensions.
Case Study 2: Conversion of a Porch to a Sunroom for a Building of Heritage Significance
Sally inherited an incredible Federation Queen Anne-style house and wanted to add an additional room at the rear of her dwelling, creating additional living space for her home. As the works appeared minor, Sally had no knowledge that approval was required for her development.
After the work had been completed, the local Council identified the change to the heritage significant building and ordered for the building to be reverted to its previous state. Sally consulted with Council and decided to submit the Building Information Certificate application herself, along with a set of plans, a survey of the site, and a brief description of the works.
In Sally’s case, after the application had been submitted, the Council requested a Heritage Impact Statement (HIS), a Statement of Environmental Effects (SEE), a Certificate of Structural Adequacy, and Stormwater Plans for the application.
Sally needed a Corona Projects Town Planner to assist her with their expert knolwedge in Heritage development applications. Get in touch.
Case Study 3: Unauthorised House Extensions
Unauthorised house extensions vary in complexity and can raise many types of issues including those relating to the Building Code of Australia (BCA) compliance and stormwater drainage.
In this case, Jake had recently decided to extend the rear portion of his house to accommodate a new rumpus room without approval. His neighbours noticed this and reported the development to his local Council. Council then followed up on the alleged building works with a site visit and issued Jake a demolition order for his newly constructed rumpus room. Jake then engaged a Corona Projecgts Town Planner to assist with the Building Information Certificate (BIC) application process.
The local Council advised that they would conditionally issue a BIC for the extension if remedial works were completed to comply with the BCA. Jake, in collaboration with his licensed builder, completed the remedial works and provided BCA certification which resulted in the issuance of the BIC.
How can Corona Projects help you?
There are many more instances of unauthorised works and case studies, each with their own unique circumstances.
If you are in a situation where the local Council has issued a Notice of Intention to Give an Order or a Development Control Order, or if you wish to sell your property and require certification for unauthorised building works, Corona Projects can assist.
Corona Projects can provide clear guidance and assist with organising the necessary information for the council to assess the situation appropriately.