Answers
Duplex & Dual Occupancy, Frequently Asked Questions
The questions we're asked most, grouped by topic. Can't find yours? A quick call is the fastest way to a preliminary read on your block.
Feasibility
Often, but it depends on your zoning (typically R2 or R3), lot size and frontage, any overlays (flood, bushfire, heritage), servicing and your subdivision goals. The fastest way to know is a feasibility check, send us your address and we'll review the controls. This is preliminary until your survey and Section 10.7 planning certificate are reviewed, and we never guarantee approval.
'Dual occupancy' is the NSW planning term for two dwellings on one lot. A duplex is the most common form, two attached dwellings side-by-side. Dual occupancy can also be detached (two separate homes) depending on the controls that apply to your site.
Under the Low Rise Housing Diversity Code, a common CDC benchmark is a minimum 450m² lot with a 12m frontage in eligible R2/R3 zones, but many councils set different minimums in their LEP, and a DA can sometimes work where CDC can't. We check your specific council's controls, not a rule of thumb.
LMR housing reforms
The LMR reforms rezone land within an 800m walking catchment of nominated town centres and stations across Sydney, the Central Coast, Illawarra-Shoalhaven and the Hunter to permit dual occupancies, terraces, townhouses, manor houses and residential flat buildings in eligible residential zones, with non-refusal standards protecting compliant proposals.
Use our instant LMR checker, enter your address and it tests the NSW Government's LMR mapping to tell you whether you're inside a catchment and which distance band. It's indicative only; we confirm eligibility properly as part of a free preliminary feasibility review.
No. Eligibility puts new housing types on the table, but your zone, lot size, frontage, overlays (flood, bushfire, heritage) and the Housing SEPP's standards decide what's actually achievable. That's exactly what a feasibility review resolves, before you spend on plans.
Approvals (DA / CDC)
CDC (Complying Development) is a fast-track pathway, as quick as around 20 days, where every standard is met. A DA (Development Application) is assessed by council against the LEP and DCP and suits sites that don't fully meet CDC standards or need design merit. We review both and recommend the pathway most likely to get your duplex approved.
A CDC can be issued in as little as ~20 days once documentation is complete. A DA typically takes longer and varies by council, submission quality and whether an RFI (request for information) is issued. See our cost & timeline guide for honest ranges.
Difficult sites
Frequently, yes, but often via DA rather than CDC. The Low Rise Housing Diversity Code excludes battle-axe lots and heritage-listed properties from CDC, so those usually route to a DA with a considered design. Narrow frontages, slope and easements all have design responses. We assess the constraint first and find a viable path before you spend on full plans.
A refusal or RFI isn't the end. We review the reasons for refusal, redesign where needed, and coordinate a planning response, which may include a Clause 4.6 variation where a development standard is exceeded for good planning reasons. Send us the council letter and we'll tell you the options.
Subdivision
Separate titles aren't automatic just because you build a duplex. Torrens subdivision creates two standalone land titles (usually higher resale value); strata subdivision divides the building. The right path must be planned from the first sketch and coordinated with a surveyor and certifier. We build subdivision intent into the design from day one.
Working with us
We work across Greater Sydney, with dedicated experience in the Sutherland Shire, Georges River, Bayside, Canterbury-Bankstown, Ryde, Randwick, Inner West, Blacktown, Cumberland, Liverpool, Fairfield and the Northern Beaches. If your council isn't listed, call us, we very likely cover it.
The fastest start is a phone call. Have your address handy (and a survey or planning certificate if you have one) and we'll give you a preliminary read on whether a duplex is possible and which approval pathway fits.
Not sure if your block can take a duplex?
Send your address, survey or council letter, or just call. We'll give you a preliminary read on what's possible.

