Western Sydney 85sqm Secondary Dwellings in Lower Airport Noise Zones
A Western Sydney 85sqm granny flat is again possible on selected lots in the airport precinct where NSW planning maps place them in the lower ANEC 20–25 band, if the design includes noise attenuation and a certifier signs off. Updated 7 August 2026.
The NSW Government ministerial release (19 May 2026) documents amendments to the Western Parkland City State Environmental Planning Policy. Industry commentators including Kobo Projects and Buildana have summarised the 85 m² cap and acoustic glazing requirements for landowners researching feasibility in Wollondilly, Camden, Fairfield, Liverpool, and Penrith.
Disclaimer: General information only, not planning or legal advice. Confirm your lot on official ANEC mapping, council zoning, and with an accredited certifier.
What the 85sqm cap means on the ground
Secondary dwellings in this context are backyard studios and granny flats, not dual occupancy knockdown-rebuilds on every lot. The policy reversal targets land previously caught by airport noise controls that blocked new noise-sensitive housing while Western Sydney International Airport (WSI) approaches operations.
Eighty-five square metres is enough for a compact two-bedroom layout if the designer prioritises acoustic walls and glazing without wasting depth on oversized hallways. Builders active in the corridor quote additional costs for double glazing, roof insulation upgrades, and sometimes mechanical ventilation so indoor noise criteria align with airport planning assumptions.
Higher-noise contours closer to the runway remain restricted. Sharing a postcode with Horsley Park or Bringelly does not prove your title sits in the eligible band.
How this sits under wider NSW secondary dwelling rules
Where airport SEPP provisions do not override them, standard Housing SEPP secondary dwelling controls still apply: setbacks, landscaping, parking in some zones, and the choice between complying development and development application pathways on trickier lots.
Certifiers familiar with ANEC documentation are worth shortlisting. A Housing SEPP template alone may miss acoustic schedules NSW Planning expects near WSI.
Practical checks before you pay a deposit
Request a contour search against current ANEC GIS layers, not a verbal council guess. Fairfield City Council’s May 2026 airport planning update illustrates how LGAs communicate partial restoration of rights along the 20 ANEC corridor.
Budget acoustic products early. Lead times on high-performance windows can exceed standard residential supply chains. Align builder progress payments with certifier stages so you are not paying for lock-up before noise details are signed off.
If you are comparing suppliers, read our certifier-first checklist for airport zone granny flats published in June 2026.
Why industry blogs matter here
NSW Planning PDFs are authoritative but dense. Builder-facing write-ups from firms such as Kobo Projects and Buildana often translate contour language into “can I build on my block?” questions. Treat them as orientation, then verify every claim against government mapping and your certifier’s written advice.
Media coverage from ABC News on the May announcement remains a useful plain-English summary of which suburbs stayed excluded.
Frequently Asked Questions
Is 85sqm automatic anywhere in Western Sydney?
No. You need eligible ANEC 20–25 mapping, compatible zoning, and compliance with acoustic and general SEPP standards.
Does the 85sqm rule apply in Sydney’s east?
No. This is a Western Parkland City airport SEPP layer. Elsewhere in NSW the usual 60 m² CDC benchmark still dominates unless another policy applies.
Can I skip noise attenuation to save cost?
No. Attenuation is part of the policy package for permitted secondary dwellings in these contours.
Primary sources
These cards are an editorial summary of official pages. The Granny Flat Guide is not a certifier, council or licensed builder. Check the live official URL before you lodge or sign.
- Your Home (Australian Government)Your Home: Australia's guide to environmentally sustainable homes
- Australian Building Codes BoardNational Construction Code
