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Duplex Builder Warriewood — CDC-Ready Designs, 15-Day Approval

Warriewood 2102 duplex specialists. Compliant design means CDC approval in ~15 business days, construction complete in 10–14 months. Feasibility within 48 hours.

Based in Fairfield, Western Sydney5.0 Google RatingLicensed & Insured (LIC 487805C)HIA Member — Buildana Custom Home Builders SydneyHIA MemberMaster Builders Association NSW Member — BuildanaMBA NSW0476 300 300
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Quick Answer

A duplex in Warriewood costs $750,000–$1,500,000+ for dual occupancy construction. Attached duplex from $750K, detached from $1M. Buildana manages feasibility, Northern Beaches Council approvals, construction and subdivision under one fixed-price contract.

Dual Occupancy Developments in Warriewood

Duplex in Warriewood works the Warriewood Valley Release Area master-planned medium density and 600m²+ R2 on original streets — Coastal Hazard, CASS. End values $2.0M–$3.2M per attached dwelling.

For a duplex in Warriewood, the economics are the framing question. Median price $2.4M–$5M+ (oceanfront); build cost on 300–800m² (master-planned + original) blocks scales by site conditions and specification. Class Hawkesbury Sandstone predominant (deep rock excavation $40K–$150K+ on most lots) / Class P/E coastal alluvial on Narrabeen/Curl Curl/Dee Why/Manly/Mona Vale lagoon corridors / coastal acid sulphate soils (CASS) on lagoon margins / coastal hazard zones on Collaroy–Narrabeen, Curl Curl, Dee Why, Manly, Mona Vale, Palm Beach beachfronts ground (extremely reactive clay) keeps foundations honest — $45,000–$80,000 band — and blowouts on that line are the single most common reason fixed-price contracts elsewhere don't stay fixed. Buildana itemises the slab, structural engineering, and geotech work upfront so you see the actual cost in the contract. R3 zoning in pockets of Warriewood opens up dual occupancy potential — worth exploring even if you're not initially considering it.

Buildana manages the full duplex development process in Warriewood — 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 Warriewood from $750K
  • Northern Beaches Council DA and CDC approvals managed
  • R2 and R3 zones — established dual occ. provisions
  • Minimum lot size 600m² (Manly/Pittwater legacy R2) / 700m² (Warringah legacy R2) / varies by precinct under Northern Beaches LEP in Warriewood
  • Class Hawkesbury Sandstone predominant (deep rock excavation $40K–$150K+ on most lots) / Class P/E coastal alluvial on Narrabeen/Curl Curl/Dee Why/Manly/Mona Vale lagoon corridors / coastal acid sulphate soils (CASS) on lagoon margins / coastal hazard zones on Collaroy–Narrabeen, Curl Curl, Dee Why, Manly, Mona Vale, Palm Beach beachfronts soil — engineered dual-slab design included
  • Strata or Torrens title subdivision available
  • 6-year structural warranty per dwelling
  • Free feasibility check — near B-Line bus to CBD (Mona Vale interchange) station
Fixed-price duplex in Warriewood near Warriewood Beach + Warriewood Square + Warriewood Valley Release
OA

Reviewed by Oliver Alameri

Licensed Builder (NSW 487805C) · Master of Property Development · PhD Student · Building across Western Sydney since 2010

Why Build a Duplex in Warriewood?

Warriewood is the oceanfront and master-planned-release suburb — Federation beach houses, post-war brick on the original streets and 2010s+ master-planned R3/R4 medium-density on the Warriewood Valley Release Area on 300–600m² blocks. Coastal Hazard zone on direct beachfront. Hawkesbury Sandstone with rock excavation typical. Warriewood Valley CASS on lagoon-margin lots. Premium oceanfront market.

Warriewood's rural-residential character and 300–800m² (master-planned + original) blocks set it apart from standard suburban development. R2 Low / R3 Medium (Manly, Dee Why, Brookvale, Mona Vale, Avalon town centres) / RU2 Rural Landscape (Ingleside, Terrey Hills, Duffys Forest, Oxford Falls) / E3/E4 Environmental on bushland fringe zoning means different controls apply — larger setbacks, on-site services, and site-specific engineering. Transport access via B-Line bus to CBD (Mona Vale interchange) connects Warriewood to the wider Sydney network. Dual occupancy is well-established in Warriewood's R3 zones. Minimum lot size for duplex: 600m² (Manly/Pittwater legacy R2) / 700m² (Warringah legacy R2) / varies by precinct under Northern Beaches LEP. Class Hawkesbury Sandstone predominant (deep rock excavation $40K–$150K+ on most lots) / Class P/E coastal alluvial on Narrabeen/Curl Curl/Dee Why/Manly/Mona Vale lagoon corridors / coastal acid sulphate soils (CASS) on lagoon margins / coastal hazard zones on Collaroy–Narrabeen, Curl Curl, Dee Why, Manly, Mona Vale, Palm Beach beachfronts soil (extremely reactive) is standard for Warriewood — Buildana includes engineered slab design in every quote.

Duplex feasibility on the Northern Beaches works inland R2 detached pockets meeting the legacy precinct minimums — 600m² (legacy Manly + Pittwater R2) or 700m² (legacy Warringah R2) — across Brookvale, Dee Why, Cromer, Narraweena, Beacon Hill, Allambie Heights, Wheeler Heights, North Manly, Manly Vale, Balgowlah, North Balgowlah, Forestville, Frenchs Forest, Davidson, Belrose, Collaroy Plateau and similar inland mid-tier suburbs. R3 Medium Density along Pittwater Road and around Manly, Brookvale, Dee Why, Collaroy, Narrabeen, Mona Vale B-Line interchange precincts permits attached duplex with FSR up to 0.9:1. RU2 acreage at Ingleside, Terrey Hills, Duffys Forest, Oxford Falls effectively rules out duplex (subdivision restrictions, AWTS limits, RFS BPA constraints). Heritage Conservation Areas across Manly, Fairlight, Balgowlah, Avalon, Bilgola Beach, Palm Beach, Whale Beach, Bilgola Plateau, Freshwater, Curl Curl, Collaroy, Narrabeen, Mona Vale, Newport village cores effectively rule out duplex on protected streets. Coastal Hazard zone restricts duplex on direct beachfront. End values $1.8M–$2.8M per attached dwelling on inland mid-tier; $2.6M–$4M on premium suburban (Balgowlah, Manly Vale, Forestville, Frenchs Forest); $3.5M–$6M+ on coastal-proximate (Curl Curl, Freshwater, Collaroy outside HCA, Newport outside HCA); duplex on direct oceanfront Manly/Whale Beach/Palm Beach effectively non-existent given heritage and Coastal Hazard controls. Hawkesbury Sandstone rock excavation $40K–$120K per dwelling on most sites. Bushfire-prone overlays drive specs on bushland-fringe lots ($30K–$80K per dwelling). Tree Preservation Order strict — AS4970 root-zone protection plans routine. Mandatory paid feasibility — Northern Beaches DCP setback, FSR, landscaped-area, deep-soil, BAL, Coastal Hazard, riparian and heritage overlays change the maths.

Planning Controls — Northern Beaches Council

Northern Beaches LEP 2022 (consolidating the legacy Manly, Warringah and Pittwater LEPs) & Northern Beaches DCP. Post-2016 amalgamation LGA spanning the entire ocean-and-harbour peninsula from North Head to Barrenjoey — 252 km² with 36+ residential suburbs, four lagoons, the Garigal and Ku-ring-gai Chase National Parks, and the Pittwater estuary. R2 Low Density covers most residential streets: FSR 0.5–0.55:1, building height 8.5–9m, front setback 6–7.5m, landscaped area 40–60%, deep soil 25–35%. R3 Medium Density along Pittwater Road and around station precincts (no rail — B-Line bus equivalents at Manly, Brookvale, Dee Why, Collaroy, Narrabeen, Mona Vale interchange/terminus) permits FSR up to 0.9:1. R4 High Density and B4 Mixed Use concentrated on Manly town centre + the Corso, Dee Why town centre, Brookvale, Mona Vale town centre, Avalon village core. Northern Beaches DCP duplex minimum lot varies by precinct — 600m² (legacy Manly + Pittwater R2) to 700m² (legacy Warringah R2). RU2 Rural Landscape covers the rural acreage belt — Ingleside, Terrey Hills, Duffys Forest, Oxford Falls, parts of Belrose — restricting subdivision to 2ha+ minimum. E3 Environmental Management and E4 Environmental Living overlays on bushland-fringe lots backing Garigal NP, Ku-ring-gai Chase NP, Manly Dam Reserve and Narrabeen Lagoon catchment further restrict siting. Heritage Conservation Areas extensive — Manly heritage core (the Corso, Eastern Hill, North Head precinct), Fairlight, Balgowlah, Balgowlah Heights, Clontarf, Seaforth, Avalon village, Newport village, Mona Vale, Bilgola Beach cove, Whale Beach, Palm Beach village, Freshwater village (Duke Kahanamoku surfing precinct), Curl Curl heritage streets, Collaroy village, Narrabeen heritage streets. Aboriginal cultural heritage protocols apply across most sandstone country (extensive rock-art sites, middens, engravings) — pre-DA Aboriginal Cultural Heritage Assessment routine on bushland-fringe and waterfront sites. Tree Preservation Order LGA-wide and strict — Northern Beaches retains the most extensive remnant bushland of any Sydney LGA. Hawkesbury Sandstone soil predominant — deep rock excavation $40K–$200K+ is LGA-defining (the most rock-excavation territory of any Sydney LGA on a per-build basis). Class P/E coastal alluvial on Narrabeen Lagoon, Curl Curl Lagoon, Dee Why Lagoon, Manly Lagoon and Mona Vale Lagoon corridors — suspended slab + Class P/E footing engineering and dewatering required. Coastal acid sulphate soils (CASS) on lagoon margins drive specialist dewatering and acid neutralisation protocols. Coastal Hazard zones are LGA-defining — coastal erosion line affects Pittwater Road oceanfront properties at Collaroy, Narrabeen, Curl Curl, Dee Why, Mona Vale, Palm Beach (2016 storm event reset baselines on Collaroy/Narrabeen specifically; multiple oceanfront properties since required Council coastal-hazard reports for any DA). Bushfire-prone land overlays are LGA-defining — BAL ratings BAL-12.5 to BAL-FZ across virtually all bushland-fringe lots (Belrose, Davidson, Killarney Heights, Frenchs Forest, Forestville, Beacon Hill, Cromer, Allambie Heights, Oxford Falls, Terrey Hills, Duffys Forest, Ingleside, Bayview, Church Point, Avalon, Bilgola Plateau, Whale Beach, Palm Beach, Clareville, Newport bushland-fringe). RFS Bushfire Protection Assessment routine — non-combustible cladding, ember-screened openings, sprinklered eaves on BAL-FZ, Asset Protection Zone (APZ) 10–40m+ on most acreage. AWTS on-site sewer mandatory on RU2 acreage belt (no reticulated sewer on Ingleside/Terrey Hills/Duffys Forest/Oxford Falls). Sydney Drinking Water Catchment overlay on parts of Ingleside, Terrey Hills, Duffys Forest western edges and Pittwater foreshore — restricts AWTS dispersal field siting and adds NSW Health/WaterNSW referral. Riparian setbacks 10–60m on Narrabeen Lagoon, Curl Curl Lagoon, Dee Why Lagoon, Manly Lagoon, Mona Vale Lagoon, Pittwater foreshore, Cowan Creek tributaries, Middle Harbour and North Harbour. Foreshore Building Line restrictions on direct waterfront across Pittwater (Bayview, Church Point, Clareville, Avalon, Newport), Middle Harbour (Clontarf, Seaforth, Balgowlah Heights), North Harbour (Fairlight, Balgowlah Heights) and ocean cliffs (Manly, Freshwater, Curl Curl, Narrabeen, Mona Vale, Newport, Bilgola, Avalon, Whale Beach, Palm Beach). The LGA has no rail — B-Line bus is the primary spine (Mona Vale terminus through Warringah Mall Brookvale interchange to CBD via Mosman). Beaches Link Tunnel (under construction, opening 2028) is the LGA-defining infrastructure event — twin tunnels under Middle Harbour connecting Cammeray to Balgowlah/Seaforth with portals reshaping traffic and property values across Balgowlah, Balgowlah Heights, Seaforth, Manly Vale and Manly. Northern Beaches Hospital (opened 2018, Frenchs Forest) anchors LGA medical employment and drives granny flat hospital-staff demand on Frenchs Forest, Davidson, Allambie Heights, Forestville, Belrose. Manly Hospital site redevelopment under master plan. Mona Vale Hospital site (Northern Beaches Hospital amalgamation legacy) under redevelopment. Warriewood Valley Release Area is the LGA's only active master-planned new-release on R3/R4 medium-density 300–600m² lots. Ingleside Precinct master-plan rezoning (originally proposed for ~3,400 dwellings) under review/paused. The Corso, Manly is the heritage retail spine. Avalon, Newport, Mona Vale, Collaroy, Dee Why, Brookvale and Manly are the primary commercial centres. Premium clifftop ocean-view properties at Manly, Freshwater, Curl Curl, Avalon, Bilgola, Whale Beach, Palm Beach are among Australia's most expensive residential markets ($8M–$30M+ on Palm Beach alone).

Duplex builder in Warriewood — key facts

Suburb
Warriewood, NSW 2102
Council / LGA
Northern Beaches Council (Northern Beaches)
Primary zoning
R2 Low / R3 Medium (Manly, Dee Why, Brookvale, Mona Vale, Avalon town centres) / RU2 Rural Landscape (Ingleside, Terrey Hills, Duffys Forest, Oxford Falls) / E3/E4 Environmental on bushland fringe
Typical lot size
300–800m² (master-planned + original)
Soil class
Class Hawkesbury Sandstone predominant (deep rock excavation $40K–$150K+ on most lots) / Class P/E coastal alluvial on Narrabeen/Curl Curl/Dee Why/Manly/Mona Vale lagoon corridors / coastal acid sulphate soils (CASS) on lagoon margins / coastal hazard zones on Collaroy–Narrabeen, Curl Curl, Dee Why, Manly, Mona Vale, Palm Beach beachfronts
Median house price
$2.4M–$5M+ (oceanfront)
Home era
1920s–1960s heritage + 2010s+ master-planned + premium contemporary
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

Building in Warriewood — Local Context

Site & Ground Conditions in Warriewood

Warriewood sits on Class Hawkesbury Sandstone predominant (deep rock excavation $40K–$150K+ on most lots) / Class P/E coastal alluvial on Narrabeen/Curl Curl/Dee Why/Manly/Mona Vale lagoon corridors / coastal acid sulphate soils (CASS) on lagoon margins / coastal hazard zones on Collaroy–Narrabeen, Curl Curl, Dee Why, Manly, Mona Vale, Palm Beach beachfronts soil — extremely reactive clay. For a duplex development, that rules out the cheapest off-the-shelf slab designs straight away. and pushes engineered footings into the $45,000–$80,000 range on most 300–800m² (master-planned + original) blocks here. Geotechnical testing isn't optional — every Buildana duplex in Warriewood starts with a borehole report so the slab and footings are sized to your actual block, not a generic spec. Skipping that step is how you end up with cracked cornices and sticking doors three years in. Drainage design matters too — overland flow paths on Warriewood's topography can collect water against rear setbacks if the contour survey is sloppy.

Planning Controls in Warriewood

Warriewood is zoned R2 Low / R3 Medium (Manly, Dee Why, Brookvale, Mona Vale, Avalon town centres) / RU2 Rural Landscape (Ingleside, Terrey Hills, Duffys Forest, Oxford Falls) / E3/E4 Environmental on bushland fringe with R3 Medium Density pockets. Northern Beaches Council controls FSR, height limits (typically 8.5–9m), site coverage, landscaped area minimums, and setbacks. For a duplex, the binding constraints on most 300–800m² (master-planned + original) blocks here are: front setback (around 4.5–6m), side setbacks (1.0–1.5m articulated), rear (3–6m depending on lot depth), and landscaped area (usually 35–40%). Buildana's design team works to those numbers from the first sketch — no late re-design when council comes back with comments.

Where the Money Goes on a Warriewood Duplex

Cost breakdown for a typical duplex in Warriewood: structure and frame around 30%, slab and foundations 8–14% (driven by Class Hawkesbury Sandstone predominant (deep rock excavation $40K–$150K+ on most lots) / Class P/E coastal alluvial on Narrabeen/Curl Curl/Dee Why/Manly/Mona Vale lagoon corridors / coastal acid sulphate soils (CASS) on lagoon margins / coastal hazard zones on Collaroy–Narrabeen, Curl Curl, Dee Why, Manly, Mona Vale, Palm Beach beachfronts soil), roofing and external 10–12%, services (plumbing, electrical, HVAC) 12–18%, fit-out (kitchen, bathrooms, joinery) 18–25%, and finishes (paint, tiles, flooring) 8–12%. The remaining 4–6% covers approvals, certifications, and site establishment. Buildana itemises every line so you see what you're paying for — no lump sums hiding margin.

What Makes a Duplex Work in Warriewood

Warriewood (2102) is part of Northern Beaches. B-Line bus to CBD (Mona Vale interchange) station is the rail anchor for the suburb. Building well here means understanding what the suburb actually rewards — and what it punishes. Reward: thoughtful orientation, family-scale outdoor entertaining, durable materials that look right against the 1920s–1960s heritage + 2010s+ master-planned + premium contemporary streetscape, and floor plans that handle multi-generational living without feeling cramped. Punish: over-glazing on west elevations (summer heat is brutal), thin slab specs on Class Hawkesbury Sandstone predominant (deep rock excavation $40K–$150K+ on most lots) / Class P/E coastal alluvial on Narrabeen/Curl Curl/Dee Why/Manly/Mona Vale lagoon corridors / coastal acid sulphate soils (CASS) on lagoon margins / coastal hazard zones on Collaroy–Narrabeen, Curl Curl, Dee Why, Manly, Mona Vale, Palm Beach beachfronts ground, generic project-home elevations that ignore the street rhythm. Buildana has built across Northern Beaches long enough to know where the line sits.

What Recent Approvals Show

Northern Beaches Council's recent decisions for Duplexs in Warriewood reveal a clear pattern — applications that lock in compliant FSR (under 0.5:1 in most cases), maintain proper articulation, and address neighbour overshadowing on the front foot are getting through cleanly. Sloppy lodgement adds 4-8 weeks of round-trip; clean lodgement doesn't.

Builder's Take on Warriewood

Duplex returns in Warriewood work only if the construction contract is fixed. I've seen people get tempted by "cost plus" arrangements that come in $200K over at handover. When you're building two dwellings simultaneously, any margin erosion doubles. Fixed price isn't just nice-to-have on a duplex — it's the only sane structure.

Strata vs Torrens in Warriewood: Torrens is cleaner if your block supports the subdivision (typically needs 600m² (Manly/Pittwater legacy R2) / 700m² (Warringah legacy R2) / varies by precinct under Northern Beaches LEP or larger), and each dwelling sits on its own lot. Strata is the fallback when Torrens isn't feasible — still separately saleable but with shared structure title. Buildana draws both options into the initial feasibility.

Warriewood vs Nearby Suburbs

Warriewood vs nearby suburbs — key metrics for building a duplex.

SuburbMedian PriceTypical LotSoil ClassMin Duplex LotStation
Warriewood2102this suburb$2.4M–$5M+ (oceanfront)300–800m² (master-planned + original)Class Hawkesbury Sandstone predominant (deep rock excavation $40K–$150K+ on most lots) / Class P/E coastal alluvial on Narrabeen/Curl Curl/Dee Why/Manly/Mona Vale lagoon corridors / coastal acid sulphate soils (CASS) on lagoon margins / coastal hazard zones on Collaroy–Narrabeen, Curl Curl, Dee Why, Manly, Mona Vale, Palm Beach beachfronts600m² (Manly/Pittwater legacy R2) / 700m² (Warringah legacy R2) / varies by precinct under Northern Beaches LEPB-Line bus to CBD (Mona Vale interchange)
Mona Vale2103$2.6M–$5M+ (oceanfront)450–800m²Class Hawkesbury Sandstone predominant (deep rock excavation $40K–$150K+ on most lots) / Class P/E coastal alluvial on Narrabeen/Curl Curl/Dee Why/Manly/Mona Vale lagoon corridors / coastal acid sulphate soils (CASS) on lagoon margins / coastal hazard zones on Collaroy–Narrabeen, Curl Curl, Dee Why, Manly, Mona Vale, Palm Beach beachfronts600m² (Manly/Pittwater legacy R2) / 700m² (Warringah legacy R2) / varies by precinct under Northern Beaches LEPB-Line bus to CBD (Mona Vale interchange + terminus)
North Narrabeen2101$2.6M–$5M+ (oceanfront)450–800m²Class Hawkesbury Sandstone predominant (deep rock excavation $40K–$150K+ on most lots) / Class P/E coastal alluvial on Narrabeen/Curl Curl/Dee Why/Manly/Mona Vale lagoon corridors / coastal acid sulphate soils (CASS) on lagoon margins / coastal hazard zones on Collaroy–Narrabeen, Curl Curl, Dee Why, Manly, Mona Vale, Palm Beach beachfronts600m² (Manly/Pittwater legacy R2) / 700m² (Warringah legacy R2) / varies by precinct under Northern Beaches LEPB-Line bus to CBD (Narrabeen interchange)
Ingleside2101$3.5M–$7M+ acreage1–5ha+ acreage (RU2)Class Hawkesbury Sandstone predominant (deep rock excavation $40K–$150K+ on most lots) / Class P/E coastal alluvial on Narrabeen/Curl Curl/Dee Why/Manly/Mona Vale lagoon corridors / coastal acid sulphate soils (CASS) on lagoon margins / coastal hazard zones on Collaroy–Narrabeen, Curl Curl, Dee Why, Manly, Mona Vale, Palm Beach beachfronts600m² (Manly/Pittwater legacy R2) / 700m² (Warringah legacy R2) / varies by precinct under Northern Beaches LEPBus to Mona Vale (5 km)

Median price, soil class, and lot size shape build feasibility and final cost. Buildana assesses every site against these and other constraints during the free feasibility stage.

Have a question about your project?

Talk to our team — free site assessment and fixed-price quote.

Feasibility in 7–14 days — yes/no before you spend real money on design
Design and engineering run as a single dual-package, not two separate jobs
Northern Beaches Council DA or CDC lodged once for both dwellings
Dual slab poured in a single site mobilisation — saves weeks
Trade crews sized for dual build — roofers, plasterers, tilers don't bottleneck
Dual handover on the same week — both titles ready to settle or lease

How It Works

From First Call to Final Key

Everything that has to be right before we touch the ground. We assess your Warriewood block — lot size (typical 300–800m² (master-planned + original)), width, R2 Low / R3 Medium (Manly, Dee Why, Brookvale, Mona Vale, Avalon town centres) / RU2 Rural Landscape (Ingleside, Terrey Hills, Duffys Forest, Oxford Falls) / E3/E4 Environmental on bushland fringe zoning, setbacks, FSR, landscaped area requirements under Northern Beaches Council's LEP and DCP. Minimum lot for duplex: 600m² (Manly/Pittwater legacy R2) / 700m² (Warringah legacy R2) / varies by precinct under Northern Beaches LEP. You'll know viability before spending on design. Design phase covers unit layout, access, parking, private open space, and waste management for dual occupancy on your Warriewood site. You approve final plans before we move to lodgement.

The Warriewood construction phase. Fixed price, programmed, supervised. 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. Cleaner submission, fewer conditions, faster CC. Fixed-price construction of both dwellings from slab to keys. Class Hawkesbury Sandstone predominant (deep rock excavation $40K–$150K+ on most lots) / Class P/E coastal alluvial on Narrabeen/Curl Curl/Dee Why/Manly/Mona Vale lagoon corridors / coastal acid sulphate soils (CASS) on lagoon margins / coastal hazard zones on Collaroy–Narrabeen, Curl Curl, Dee Why, Manly, Mona Vale, Palm Beach beachfronts engineered footings, frame, lock-up, internal fit-out, and external works. Weekly progress reports.

The job isn't done when the site's clean; it's done when you have keys, certificates and warranties. Subdivision registration starts in parallel with final fitout so titles issue close to handover, not 6 months after. Buildana coordinates the surveyor and Northern Beaches Council clearance — important if you're planning to sell one side immediately to fund the next move.

Quality Promise

We build duplexes in Warriewood end-to-end — feasibility, design, DA/CDC, dual-slab construction, subdivision. One contract.

Fixed-price duplex constructionNCC 2025 and BASIX compliantFull Northern Beaches Council complianceStrata or Torrens title subdivisionWeekly progress updates6-year structural warranty per dwelling

Cost Guide

ItemEstimated Range
Attached duplex (2 × 180–220m²)$850,000 – $1,130,000
Attached duplex (2 × 220–260m²)$1,130,000 – $1,470,000
Detached duplex (2 × 220–280m²)$1,360,000 – $1,750,000
Strata/Torrens subdivision$17,000 – $34,000
Demolition (if KDR duplex)$20,000 – $45,000
Council contributions$11,000 – $68,000+

Prices are indicative for Western Sydney (2025). Actual costs depend on site, specifications, and approvals.

Our Team

OA

Oliver Alameri

Founder / Director / Builder · MPropDev · PhD Student

AA

Ahmad Alameri

Accounts Manager

CW

Claire Wendell

Project Manager

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