Extending Heritage Homes in Sydney: Regulations & Process 

Renovating and extending a heritage property is one of the best ways to increase the living space and modernise an older home. As with any construction work on a heritage-listed property, there are strict regulations for what is permitted and what is not for alteration, additions, or extensions. Heritage guidelines ensure that the heritage integrity and crafted features of the property are carefully preserved.

Heritage home extensions require balancing heritage value with modern additions – understanding the council regulations in Sydney or NSW and the building process can help prevent delays. 

Sydney Regulations for Heritage Home Extensions 

The regulations for heritage home extensions in Sydney can vary depending on the property’s heritage listing – whether it is on the NSW State Heritage Register, or locally listed in a council area. 

• Properties on the State Heritage Register will require a Section 60 Approval from the NSW Heritage Council, and a Development Application (DA) from the local council. 
• Locally listed heritage properties or buildings in a Heritage Conservation Area will only require a DA from the local council. 

Preparing the DA for a heritage home extension requires the expertise of a Heritage Architecture Studio, like Crush Architecture, and a heritage consultant to develop support documents such as the architectural plans, Statement of Environmental Effects, and Heritage Impact Statement.

Design Guidelines for Heritage Property Additions

Each council in Sydney and New South Wales has its own set of regulatory guidelines for the design of heritage property extensions, known as DCP (Development Control Plan). Heritage guidelines, Heritage Conservation Areas (HCA) or specific heritage items are identified in the LEP (Local Environmental Plan). Generally, a proposed alteration and addition to a Heritage Item or a property within a heritage conservation area should not negatively impact the streetscape, and the design should be sympathetic to the HCA itself. Other design guidelines that apply to heritage home extensions include:

• Extensions must be located at the back or side of the property, provided they are not intrusive or have a negative impact on the streetscape.
• The extension generally should be subordinate to the original building to maintain the primary relevance of the heritage building. However, there are exceptions that apply on a case-by-case basis.
• The roof typology should complement the original building and should be designed to avoid disruptions to or modifications of the main original roof.
• Generally, if the planned extension includes an additional storey, it must be set back at least 600 mm from the main roof ridge of the heritage building. 
• Additional storeys to the main building are generally not permitted. Renovation works that utilise the existing roof space may be allowed, as long as the form, slopes, and height of the roof remain the same. 
• Extensions that add a garage or carport must be located at the rear or at least behind the front building line.
• New areas of the extension must be clearly separated from the heritage home using architectural elements such as links, setback, or recessed walls. 

Additional design restrictions may apply for your local council. To avoid issues during planning, we suggest consulting a team of heritage architects early on. We can conduct a Project Analysis that considers what you want to achieve against the Planning Controls (LEP and DCP), as well as the approval precedence in your area, so we can leverage your proposal.

The Heritage Home Extension Process

1. Heritage Architect Consultation 

We meet with heritage home owners to assess the current condition of the property and discuss the goals of the extension project. 

2. Architectural Feasibility Study

We conduct a feasibility study that involves a review of the Local Environmental Plan (LEP) and the Development Control Plan (DCP), Precendences of DA Approved or Refused in your area, and Diagram options for your project and the relative budget. The results of the study outline the opportunities, risks, and limitations for the home extension. 

3. Design Development 

We start designing hand-sketched ideas and physical models, and host a workshop meeting with the client to test those ideas together. When the overall concept design is approved, we develop a detailed 3D model of the planned extension, including exact measurements and material choices. A qualified heritage consultant is brought early on in the project, so we can work together on the project and provide pre-advice. The heritage consultant will prepare the Heritage Impact Statement for the development approval. 

4. Submit Developmental Application

We work alongside the heritage consultant to prepare the necessary documents for a Development Application to the local council. Councils across New South Wales aim to make a decision on a DA within 40 days, although this timeframe can vary depending on the council’s assessment capacity and the complexity of the project. 

5. Construction 

Building work can commence when the Council issues a DA approval and the Private Certifier a Construction Certificate. We develop construction documentation for contractors and trade work, serve as Contract Administrator for the Construction Contract, and oversee the entire building process to ensure every aspect is built according to plan.  

Crush Architecture is a team of award-winning heritage architects in Sydney, specialising in updating heritage-listed homes for modern needs while paying homage to their history. Our architectural team also holds Passivhaus certification – we incorporate passive house designs into a planned extension for greater energy efficiency and year-round comfort. Contact our team today to arrange an initial consultation for your heritage home extension.