Licensed Granny Flat Specialist Collaroy
NSW licensed builder delivering SEPP-compliant granny flats across Collaroy 2097. BASIX, engineered slab (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), full certifier sign-off and 6-year structural warranty.
HIA Member
MBA NSW0476 300 300Quick Answer
A granny flat in Collaroy costs $150,000–$300,000+ depending on size and finishes. 1-bed from $150K, 2-bed from $200K. CDC fast-track approval in 10–15 business days. Buildana manages design, Northern Beaches Council approval and fixed-price construction.
Granny Flat Builder in Collaroy
Granny flat in Collaroy delivers $750–$950/week — beach-proximate premium, HCA restricts placement on village core, salt-grade specs. Realistic build cost $260K–$430K.
On the ground in Collaroy (2097), the practical numbers shape every granny flat. 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 — pushes engineered foundation work into the $45,000–$80,000 bracket on most 450–900m² blocks. 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 under Northern Beaches Council sets the building envelope, with R3 Medium Density pockets that open up dual occupancy options on qualifying lots. Median sale price across Collaroy sits at $2.8M–$8M+ (oceanfront), which frames the build-versus-buy decision from the start. B-Line bus to CBD (Collaroy stop) station services the suburb, and that proximity affects everything from rental demand to construction site access.
Buildana manages the full granny flat process in Collaroy — from site assessment and CDC fast-track approval through to fixed-price construction and handover. We build studio, 1-bedroom, and 2-bedroom designs up to the NSW maximum of 60m².
Read our Complete Granny Flat Guide or explore granny flat builds across Sydney.
- Granny flats in Collaroy from $150K
- CDC fast-track approval (10–15 business days)
- 450–900m² blocks — most qualify for 60m² granny flat
- Collaroy 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
- Fixed-price contract — design to handover
- 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 slab included
- Rental yield $620–$900/week (beach proximity + Northern Beaches Hospital staff demand drives premium) in Collaroy
- Free site assessment — near B-Line bus to CBD (Collaroy stop) station
Reviewed by Oliver Alameri
Licensed Builder (NSW 487805C) · Master of Property Development · PhD Student · Building across Western Sydney since 2010
Why Build a Granny Flat in Collaroy?
Collaroy is the oceanfront beach suburb — Federation beach houses, inter-war heritage, post-war brick and contemporary on 450–900m² blocks. Coastal Hazard zone on direct beachfront — coastal erosion line affects Pittwater Road oceanfront properties (2016 storm event reset baselines). Hawkesbury Sandstone with rock excavation. Heritage Conservation Area covers the village. B-Line corridor.
Collaroy's rural-residential character and 450–900m² 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 (Collaroy stop) connects Collaroy to the wider Sydney network. Secondary dwellings on 450–900m² blocks deliver rental returns of $620–$900/week (beach proximity + Northern Beaches Hospital staff demand drives premium) per week. CDC approval through a private certifier typically takes 10–15 business days. Ground conditions (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) across Collaroy are well understood by local builders — Buildana's engineering accounts for extremely reactive soil movement.
Granny flats on the Northern Beaches deliver some of Sydney's strongest beach-proximate yields — $620–$900/week typical, $750–$1,000/week within walking distance of Manly/Freshwater/Curl Curl/Collaroy/Mona Vale/Newport/Avalon beaches, $700–$900/week in Frenchs Forest/Davidson/Allambie Heights/Forestville driven by Northern Beaches Hospital staff demand (opened 2018, Frenchs Forest), $700–$950/week on Bayview/Church Point/Clareville Pittwater-proximate lots. Block sizes 450–1,200m² across the suburban core generally accommodate compliant 60m² siting. Hawkesbury Sandstone soil predominant — sandstone footing engineering and rock excavation $20K–$80K typical (deeper on harbour/Pittwater-fall lots). Bushfire-prone overlays add BAL specs ($15K–$40K) and APZ siting constraints on bushland-fringe lots. Coastal Hazard restricts granny flat siting on direct beachfront. Coastal salt-grade specs add $5K–$15K on coastal-facing builds. Heritage Conservation Areas restrict granny flat placement on Manly/Fairlight/Avalon/Bilgola/Palm Beach/Whale Beach/Freshwater/Curl Curl/Collaroy/Narrabeen/Mona Vale/Newport village cores and protected streets. Tree Preservation Order strict — AS4970 root-zone protection plans routine on protected canopy trees. RU2 acreage at Ingleside/Terrey Hills/Duffys Forest/Oxford Falls runs AWTS on-site sewer and Sydney Drinking Water Catchment overlay (parts) — granny flat siting subject to AWTS dispersal field clearances and NSW Health/WaterNSW referral. CDC available outside heritage/bushfire/Coastal Hazard zones on compliant lots; otherwise full DA. Realistic build cost $230K–$380K for premium 60m² inland; $280K–$450K on coastal/sandstone/bushfire-spec builds; $300K–$500K on RU2 acreage with AWTS extension.
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).
Granny flat builder in Collaroy — key facts
- Suburb
- Collaroy, NSW 2097
- 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
- 450–900m²
- 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
- $2.8M–$8M+ (oceanfront)
- Home era
- 1920s–1960s heritage + premium contemporary
- Typical price range
- $150,000 – $300,000+
- Typical timeline
- 4–6 months design to handover
- Approval pathway
- CDC via NSW Affordable Rental Housing SEPP (10–15 days)
Building in Collaroy — Local Context
Collaroy Block Realities
Typical Collaroy blocks are 450–900m² 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 (extremely reactive clay). For a secondary dwelling, the structural envelope is more constrained than the headline lot size suggests — once you subtract setbacks, easements, landscaped area requirements, and any tree preservation, the actual buildable area is usually 35-45% of the block. We map that early in the feasibility stage so you're designing to what's actually allowed, not what looks possible from the title plan. Foundation cost band on most Collaroy blocks: $45,000–$80,000.
Planning Controls in Collaroy
Collaroy 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 secondary dwelling, the binding constraints on most 450–900m² 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 Collaroy Secondary dwelling
Cost breakdown for a typical secondary dwelling in Collaroy: 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.
Designing for the Collaroy Streetscape
Collaroy's housing stock is predominantly from the 1920s–1960s heritage + premium contemporary. B-Line bus to CBD (Collaroy stop) station is the rail anchor for the suburb. The local anchor is Collaroy Beach + Collaroy Surf Life Saving Club + Long Reef Headland. For a granny flat, the streetscape question matters more than most builders admit — a brand-new double-storey on a street of single-storey 1920s–1960s heritage + premium contemporary weatherboards will draw council attention on bulk and scale, even if technically compliant. Buildana designs the front elevation to read appropriately for the street while modernising the floor plan and structure behind it. Materials palette, roof pitch, fenestration rhythm — all chosen to settle into the existing rhythm rather than fight it.
Why Some Collaroy Builds Stall
Builds in Collaroy stall for predictable reasons. Lodgement defects (missing BASIX, wrong drawing scale, undeclared overlays). Soil surprises 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 when the builder didn't commission a borehole upfront. Variation creep when the contract was light on inclusions. Trade scheduling gaps when the builder is over-committed across too many sites. Northern Beaches Council delays when neighbour objection triggers committee review. Buildana protects against each of these at contract stage — fully documented lodgement pack, geotech in the price, itemised inclusions instead of allowances, and a tight project-manager-to-job ratio that keeps trades moving.
Builder's Take on Collaroy
On a 450–900m² block in Collaroy, granny flat placement matters more than finishes. Too close to the main house and privacy fails. Too deep in the yard and services cost triples. Best placement is usually along a side boundary with a clear walkway from the street — respects the front home's curb appeal.
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 affects granny flat slab costs same as a main dwelling — roughly $3K–$10K uplift over standard. Not a dealbreaker but worth including in the quote. Cheapest granny flat quotes in the market usually exclude this and add it at variation.
Collaroy vs Nearby Suburbs
Collaroy vs nearby suburbs — key metrics for building a granny flat.
| Suburb | Median Price | Typical Lot | Soil Class | GF Rental | Station |
|---|---|---|---|---|---|
| Collaroy2097this suburb | $2.8M–$8M+ (oceanfront) | 450–900m² | 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 | $620–$900/week (beach proximity + Northern Beaches Hospital staff demand drives premium) | B-Line bus to CBD (Collaroy stop) |
| Collaroy Plateau2097 | $2.4M–$3.8M | 500–800m² | 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 | $620–$900/week (beach proximity + Northern Beaches Hospital staff demand drives premium) | B-Line bus to CBD (Collaroy interchange) |
| Narrabeen2101 | $2.6M–$5.5M+ (oceanfront) | 450–800m² | 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 | $620–$900/week (beach proximity + Northern Beaches Hospital staff demand drives premium) | B-Line bus to CBD (Narrabeen interchange) |
| North Narrabeen2101 | $2.6M–$5M+ (oceanfront) | 450–800m² | 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 | $620–$900/week (beach proximity + Northern Beaches Hospital staff demand drives premium) | B-Line bus to CBD (Narrabeen interchange) |
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.
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How It Works
From First Call to Final Key
We inspect your Collaroy block — lot size (typical 450–900m²), setbacks, services, access, 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 check and Northern Beaches Council requirements. You'll know if a granny flat is feasible before spending a dollar.
⏱Design phase covers layout, orientation on your Collaroy block, bathroom and kitchen placement, natural light, privacy screening, and entry path. You approve the design before we move to certification.
⏱Approval pack lodged with our preferred private certifier (Buildana works with several across the Northern Beaches area). They've reviewed our designs before, know our documentation standard, and turn approvals around at the fast end of the legislated window.
⏱Construction runs 10–16 weeks from slab pour. 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 slab, timber or steel frame, Colorbond roof, full internal fit-out, and separate service connections. Weekly updates from your project manager.
⏱Handover documentation includes everything you need to list with a property manager: OC, BASIX, structural cert, appliance manuals, separate metering details. Photos for the listing taken before furniture goes in. Most Collaroy GFs lease within 2 weeks.
⏱Quality Promise
Every Buildana granny flat in Collaroy is built under a fixed-price contract with full Collaroy council compliance and a 6-year structural warranty.
Cost Guide
| Item | Estimated Range |
|---|---|
| Attached granny flat | $190,000 – $260,000 |
| Detached granny flat | $220,000 – $310,000 |
| Above-garage granny flat | $270,000 – $350,000 |
| Premium detached (upgraded finishes) | $310,000 – $380,000 |
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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“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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Last updated: 1 July 2025
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