Greenwich Duplex Builder — Western Sydney Dual Occupancy
Buildana is a local Lane Cove duplex builder. We know which Greenwich streets support Torrens title subdivision, which suit strata, and what Lane Cove Council will approve. Free site feasibility.
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MBA NSW0476 300 300Quick Answer
A duplex in Greenwich costs $750,000–$1,500,000+ for dual occupancy construction. Attached duplex from $750K, detached from $1M. Buildana manages feasibility, Lane Cove Council approvals, construction and subdivision under one fixed-price contract.
Duplex Builder in Greenwich
A duplex in Greenwich is rarely the play, because near-total heritage coverage, deep rock and a premium harbour market favour a single home. This harbour-fall peninsula runs Federation mansions and inter-war heritage on 500 to 1,200m2 blocks with substantial fall to Sydney Harbour, and Heritage Conservation Areas cover most streets, so a dual-occupancy is constrained or precluded on contributory lots. At a $3.5M to $8.0M market a single premium residence usually returns more than splitting a block.
The sandstone-dominant soil and harbour fall mean deep rock excavation and substantial retaining, so a duplex spreads a very high site cost across two footprints. I would rather give you the honest read than push the wrong product. Where the existing home carries fibro a licensed asbestos strip-out comes first.
What I would check first on your Greenwich block: the heritage status, whether a single premium home is the clear best use, and the deep rock and harbour-fall retaining. That decides the direction.
We build these fixed-price, licence HBL 487805C. Send me the address and I will tell you honestly what the block suits.
Buildana manages the full duplex development process in Greenwich — from feasibility assessment and architectural design through to DA or CDC approval, and fixed-price construction to dual handover. One builder, one contract, two homes.
Read our Complete Duplex Building Guide or explore duplex developments across Sydney.
- Dual occupancy in Greenwich from $750K
- Lane Cove Council DA and CDC approvals managed
- R2 and R3 zones — established dual occ. provisions
- Minimum lot size 550m² in Greenwich
- M — engineered dual-slab design included
- Strata or Torrens title subdivision available
- 6-year structural warranty per dwelling
- Free feasibility check — near Wollstonecraft (1.5 km, ferry) station
Reviewed by Oliver Alameri
Licensed Builder (NSW 487805C) · Master of Property Development · PhD Student · Building across Western Sydney since 2010
Heritage and premium harbour
This harbour-fall peninsula runs Federation mansions and inter-war heritage on 500 to 1,200m2 blocks with substantial harbour fall.
Conservation Areas cover most streets, so a dual-occupancy is constrained or precluded, at a $3.5M to $8.0M market.
Deep rock and retaining
The sandstone-dominant soil and harbour fall mean deep rock excavation and substantial retaining across both dwellings.
A duplex spreads a very high site cost across two footprints, with older fibro stripped under licence first.
Duplex builder in Greenwich — key facts
- Suburb
- Greenwich, NSW 2065
- Council / LGA
- Lane Cove Council (Lane Cove)
- Primary zoning
- R2 Low Density
- Typical lot size
- 500–1,200m²
- Soil class
- M
- Median house price
- $3.5M–$8.0M
- Home era
- 1880s–1940s heritage
- Typical price range
- $750,000 – $1,500,000+
- Typical timeline
- 14–22 months design to handover
- Approval pathway
- CDC for compliant dual-occupancy, else DA
Want a real number for YOUR block — not a generic estimate?
Free site assessment, fixed-price contract, line-itemised quote within 48 hours. No high-pressure sales — just a real builder talking real numbers.
How It Works
From First Call to Final Key
We assess your Greenwich block — lot size (typical 500–1,200m²), width, R2 Low Density zoning, setbacks, FSR, landscaped area requirements under Lane Cove Council's LEP and DCP. Minimum lot for duplex: 550m².
⏱Design phase covers unit layout, access, parking, private open space, and waste management for dual occupancy on your Greenwich site. You approve final plans before we move to lodgement.
⏱Duplex approvals get scrutinised harder than single dwellings — neighbour notification, overshadowing, privacy, traffic, waste. Our SEE addresses each on the front foot rather than reactively.
⏱Fixed-price construction of both dwellings from slab to keys. Class M engineered footings, frame, lock-up, internal fit-out, and external works.
⏱Subdivision registration starts in parallel with final fitout so titles issue close to handover, not 6 months after. Buildana coordinates the surveyor and Lane Cove Council clearance — important if you're planning to sell one side immediately to fund the next move.
⏱Quality Promise
Greenwich dual occupancy construction: feasibility assessment first, then fixed-price build to dual handover. No surprises.
Cost Guide
| Item | Estimated Range |
|---|---|
| Vacant R2/R3 block in Greenwich — duplex build | $960,000 – $1,920,000 |
| KDR duplex (demo 1880s–1940s heritage home + dual build) | $1,050,000 – $2,050,000 |
| Subdivision-ready block (existing survey & titles) | $960,000 – $1,790,000 |
| Corner block dual-frontage duplex | $1,150,000 – $2,050,000 |
| Investor scenario (neutral-gear focus, rental-ready) | $1,090,000 – $1,600,000 |
Prices are indicative for Western Sydney (2025). Actual costs depend on site, specifications, and approvals.
Our Team
Oliver Alameri
Founder / Director / Builder · MPropDev · PhD Student
Ahmad Alameri
Accounts Manager
Claire Wendell
Project Manager
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Still got questions? Talk to Oliver directly.
30-min free call — bring your block, your brief, your budget. We'll map out feasibility, timeline, and realistic cost. No sales pitch.
Frequently Asked Questions
Buildana built our granny flat in just 12 weeks. Fast approvals, great communication, and a beautiful final product. Highly recommend.
Fatima Al-Rashid
Liverpool, NSW
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Headquartered in Western Sydney's Fairfield. Active across all 28 metropolitan Sydney LGAs — from Penrith to the Eastern Suburbs, the Hills to the Sutherland Shire.
Last updated: 1 July 2025
Build a Duplex in Greenwich
Free duplex feasibility assessment for Greenwich 2065. We'll check your block, estimate yield, and provide a fixed-price budget.
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Other Buildana services in Greenwich
Costs, approval pathway and fixed-price contract detail for every other build type we deliver in Greenwich 2065. Lane Cove Council regulations and local controls are covered on each page.