Duplex Builder Jannali — From $750K Fixed Price
Fixed-price duplex construction in Jannali 2226. Two dwellings, one contract, no variations. Minimum lot 700m² under Sutherland Shire DCP 2015 (higher than most LGAs). Free feasibility.
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MBA NSW0476 300 300Quick Answer
A duplex in Jannali costs $750,000–$1,500,000+ for dual occupancy construction. Attached duplex from $750K, detached from $1M. Buildana manages feasibility, Sutherland Shire Council approvals, construction and subdivision under one fixed-price contract.
Jannali Dual Occ. — Feasibility to Handover
A duplex in Jannali works on the larger lots that clear the Sutherland 700m2 minimum, with foreshore constraints on the river-frontage streets. This quiet suburb backing the Georges River foreshore at Como runs 1960s to 1990s fibro and brick veneer on 550 to 800m2 R2 blocks, so the larger lots clear 700 while smaller ones fall short. Foreshore lots carry a Foreshore Building Line and a Crown Lands referral on river-frontage works, so those checks lead near the water.
The ground is Hawkesbury Sandstone bedrock, so stepped blocks carry deep substructure scope and a duplex spreads that across two footprints. On a qualifying inland lot a side-by-side works cleanly. Where the existing home carries fibro a licensed asbestos strip-out comes first.
What I would check first on your Jannali block: whether it clears the 700m2 Sutherland minimum, any Foreshore Building Line on river-frontage lots, and the rock on stepped blocks. Those set the dual-occ.
We build these fixed-price, licence HBL 487805C. Send me the block and I will tell you what dual-occupancy it carries.
Buildana manages the full duplex development process in Jannali — 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 Jannali from $750K
- Sutherland Shire Council DA and CDC approvals managed
- R2 and R3 zones — established dual occ. provisions
- Minimum lot size 700m² under Sutherland Shire DCP 2015 (higher than most LGAs) in Jannali
- Hawkesbury Sandstone bedrock — engineered dual-slab design included
- Strata or Torrens title subdivision available
- 6-year structural warranty per dwelling
- Free feasibility check — near Jannali station
Reviewed by Oliver Alameri
Licensed Builder (NSW 487805C) · Master of Property Development · PhD Student · Building across Western Sydney since 2010
Feasibility against 700m2
This quiet foreshore suburb runs 1960s to 1990s stock on 550 to 800m2 R2 blocks, so the larger lots clear the Sutherland 700m2 minimum.
Foreshore lots carry a Foreshore Building Line and a Crown Lands referral on river-frontage works, so those checks lead near the water.
Rock on stepped blocks
The Hawkesbury Sandstone bedrock means stepped blocks carry deep substructure scope, spread across both dwellings on a duplex.
On a qualifying inland lot a side-by-side works cleanly, with older fibro stripped under licence first.
Duplex builder in Jannali — key facts
- Suburb
- Jannali, NSW 2226
- Council / LGA
- Sutherland Shire Council (Sutherland Shire)
- Primary zoning
- R2 Low Density predominant
- Typical lot size
- 550–800m² typical; 600–1,000m² premium beachside/foreshore (Cronulla/Burraneer/Lilli Pilli/Yowie Bay/Caringbah South/Sylvania Waters); 700–2,000m² bushland-fringe (Bundeena, Maianbar, Bangor, Menai)
- Soil class
- Hawkesbury Sandstone bedrock
- Median house price
- $1.4M–$2.2M mid-tier; $1.8M–$3.8M foreshore; $2.5M–$6.0M+ Cronulla/Burraneer/Lilli Pilli/Caringbah South premium beachside
- Home era
- 1960s–1990s fibro/brick veneer predominant + 1990s–2010s brick
- 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.
Cost Guide
| Item | Estimated Range |
|---|---|
| Standard attached duplex — base spec | $750,000 – $950,000 |
| Upgraded finishes (stone, ducted A/C, upgraded kitchens) | $950,000 – $1,200,000 |
| Premium duplex (architect design, hydronic, landscape package) | $1,200,000 – $1,550,000 |
| Luxury detached dual occupancy | $1,550,000+ |
Prices are indicative for Western Sydney (2025). Actual costs depend on site, specifications, and approvals.
How It Works
From First Call to Final Key
A duplex is really a feasibility problem wearing a construction outfit. Before anything else, we verify your Jannali block against Sutherland Shire Council's LEP — lot size, frontage, FSR, landscape area. If it doesn't stack up, you find out in a week, not after 3 months of design.
⏱Design runs dual from day one. Two dwellings, one coherent streetscape, party-wall acoustics and fire rating built into the structure rather than bolted on. The plan accommodates R2 Low Density predominant zoning without looking like two mismatched houses sharing a fence.
⏱Approval and construction get sequenced together. Slab pours are choreographed so the trades show up once, frame up both sides, and keep rolling. Two separate meters, two separate services, but one crew, one programme.
⏱Handover is dual. Both dwellings walked at the same time, both OCs in the same issue, both titles subdivided before settlement. You leave the final inspection with the option to live in one and rent the other, or to sell both.
⏱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.
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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.
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Other Buildana services in Jannali
Costs, approval pathway and fixed-price contract detail for every other build type we deliver in Jannali 2226. Sutherland Shire Council regulations and local controls are covered on each page.