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Our online visualisation and cost estimator gives you a quick preliminary read on whether a granny flat could work on your land. Simply enter your address to get started.
Key Requirements for Building a Granny Flat in NSW
Before committing to a granny flat project, it pays to understand the regulatory framework. Below is a summary of the most important rules that apply state-wide.
Key Requirements
Requirements Overview
Maximum Internal Floor Area
Granny flats in New South Wales are limited to 60 m² of internal living space, ensuring the secondary dwelling remains proportionate to the primary residence.
Minimum Lot Size
To qualify under standard complying development rules, the property must have a minimum lot size of 450 m².
Minimum Street Frontage
Street frontage requirements vary :
• 12 metres for lots under 900 m²
• 15 metres for lots between 900–1,500 m²
• 18 metres for lots over 1,500 m²
• 12 metres for lots under 900 m²
• 15 metres for lots between 900–1,500 m²
• 18 metres for lots over 1,500 m²
Maximum Internal Floor Area
Granny flats can be approved through one of two pathways:
• Complying Development Certificate (CDC) issued by a private certifier
• Development Application (DA) assessed by your local council
• Complying Development Certificate (CDC) issued by a private certifier
• Development Application (DA) assessed by your local council
Dwelling Classification
A granny flat is legally classified as a secondary dwelling, meaning a primary home must already exist on the property or have its own approval.
One Per Property
Current NSW legislation permits only one granny flat per property title.
Battle-Axe Access
For battle-axe blocks, the access driveway must be at least 3 metres wide to allow adequate vehicle access.
Requirements
Link to Detailed Requirements
For the complete setback, site coverage and landscaping tables broken down by lot size, visit our detailed guide:
Approval Pathways Note
If your property doesn’t satisfy every CDC criterion, a Development Application (DA) may still allow a granny flat to be approved.
Our team prepares and lodges both CDC and DA applications on a daily basis, ensuring the most appropriate pathway is chosen for each property.
Completed Projects
Recent Granny Flat Projects Across Sydney
Each GrannyFlow project begins with a detailed understanding of the homeowner’s property, goals and constraints — from investment-focused one-bedroom builds to larger family homes across Sydney’s Western suburbs, Inner West and beyond
