Can I Build a Second Dwelling on My Block Without Subdividing?

If you’re considering building a second dwelling on your property in New South Wales, one of the first questions you’ll ask is whether subdivision is required.

The good news is that in many cases, you can build without subdividing — but only if your plans comply with NSW planning rules.

At Town Planning Sydney, we help homeowners understand what’s allowed, what isn’t and how to get council approval for a second dwelling without unnecessary costs or delays.

Here’s what you need to know before moving forward.

1. A second dwelling does not always need subdivision

In NSW, you can build a second dwelling on your land without creating a separate title.

This is commonly known as a secondary dwelling or granny flat.

Secondary dwellings are permitted under NSW planning policies as long as certain controls are met.

These include minimum lot size, location within a residential zone and compliance with floor space and setback rules.

2. Secondary dwellings can be approved via CDC or DA

There are two ways to get approval, through a Complying Development Certificate (CDC) or a development application to council.

If your site meets CDC criteria, you can build without subdivision or public notification.

Our planning consultants assess your site and determine the best pathway.

In a recent project in Blacktown, the client added a self-contained two-bedroom dwelling behind their existing home without subdividing.

The design was CDC-compliant and approved in less than four weeks.

3. Dual occupancies usually require more planning and sometimes subdivision

Dual occupancy refers to two separate dwellings on the same lot. These are often attached or detached homes that may or may not share walls.

Some councils allow dual occupancy without subdivision, but others require it if separate ownership is intended.

We provide detailed planning advice to help you understand what’s possible on your land.

In Ryde, we helped a client lodge a dual occupancy development application without subdivision by designing to meet shared access and private open space rules.

4. Councils may approve second dwellings without subdivision if planning controls are met

Each local government area has different rules under their Development Control Plan (DCP).

You need to consider setbacks, building height, parking and landscape requirements.

We recently secured DA approval in Inner West Council for a second dwelling on a corner block without subdividing.

Our team prepared plans, justified the proposal in the Statement of Environmental Effects and responded to council’s concerns on overshadowing.

5. Subdivision is a separate process with added costs and conditions

If you do plan to subdivide in the future, it will require a different type of development application.

Subdivision requires additional assessment, drainage strategy and sometimes contributions to local infrastructure.

We help clients plan for staged approvals if they intend to subdivide later.

In a Campbelltown case, we advised the client to build the second dwelling first, then lodge a subdivision DA once infrastructure upgrades were complete.

6. Get professional advice before committing to a design

Many people draw up second dwellings without checking if they can legally build it.

We review your site’s zoning, overlays and DCP controls before preparing any plans.

This saves time and prevents expensive redesigns.

At Town Planning Sydney, we offer planning-led drafting to help you get council approval with confidence.

If you’re thinking about adding a second dwelling, understanding what you can build without subdivision is the first step.

We guide you through NSW planning requirements and help you make the right decisions for your site.