Skip to content
Buildana construction project in Western Sydney

Knockdown Rebuild Hornsby — From $450K All-In

Fixed-price knockdown rebuild in Hornsby 2077. Demolition, new home, all Hornsby Shire Council approvals under one contract. No surprises, no variation trail.

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
?

Quick Answer

A knockdown rebuild in Hornsby costs $450,000–$1,200,000+. Standard single-storey from $450K, two-storey from $650K. Buildana manages demolition, Hornsby Shire Council approvals, and construction under one fixed-price contract.

Hornsby KDR — Single Contract, New Home

Hornsby's 1900s–1940s Federation heritage (Beecroft/Cheltenham/Pennant Hills/Wahroonga boundary) + 1960s–1990s brick (Cherrybrook/Asquith/Mount Colah/Mount Kuring-gai) + 2010s+ R3/R4 redevelopment around Hornsby/Asquith/Waitara stations-era housing stock on 700–1,200m² typical (Hornsby/Asquith/Pennant Hills/Beecroft/Wahroonga boundary/Cherrybrook); 1–5ha acreage (Galston/Berrilee/Arcadia/Forest Glen/Glenorie/Berowra Heights bushland fringe) blocks makes the suburb a strong candidate for knockdown rebuild. Many older homes in Hornsby have reached the point where renovation costs approach or exceed the cost of a complete KDR — and a new build delivers a home designed exclusively for your lifestyle, built to current NCC standards. Hornsby Shire Council manages approvals across Hornsby Shire, and Buildana has deep experience with KDR projects in the area.

For a rebuild in Hornsby, the economics are the framing question. Median price $1.8M–$2.6M Hornsby/Asquith/Mount Colah; $2.4M–$3.6M Cherrybrook/Beecroft/Pennant Hills; $3.0M–$8.0M+ Galston/Arcadia acreage; build cost on 700–1,200m² typical (Hornsby/Asquith/Pennant Hills/Beecroft/Wahroonga boundary/Cherrybrook); 1–5ha acreage (Galston/Berrilee/Arcadia/Forest Glen/Glenorie/Berowra Heights bushland fringe) blocks scales by site conditions and specification. Class Hawkesbury Sandstone bedrock predominant (saw-cutting, rock-anchoring $30K–$120K above standard substructure) / Class M Wianamatta Shale on Cherrybrook/Beecroft ridges / bushfire-prone land BAL-12.5 to BAL-FZ on virtually all bushland-fringe (most of the LGA) ground (moderately to highly reactive clay) keeps foundations honest — $24,000–$42,000 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 Hornsby opens up dual occupancy potential — worth exploring even if you're not initially considering it.

Buildana manages the complete knockdown rebuild process in Hornsby — from site assessment and architectural design through to DA or CDC approval, demolition management, and fixed-price construction to handover. One builder, one contract, one new home.

Read our KDR Cost Guide 2026 or use the Renovation vs KDR Calculator to compare options.

  • New home in Hornsby from $450K
  • Hornsby Shire Council DA and CDC approvals managed
  • Demolition and asbestos removal included
  • Class Hawkesbury Sandstone bedrock predominant (saw-cutting, rock-anchoring $30K–$120K above standard substructure) / Class M Wianamatta Shale on Cherrybrook/Beecroft ridges / bushfire-prone land BAL-12.5 to BAL-FZ on virtually all bushland-fringe (most of the LGA) soil — engineered slab design included
  • Typical blocks 700–1,200m² typical (Hornsby/Asquith/Pennant Hills/Beecroft/Wahroonga boundary/Cherrybrook); 1–5ha acreage (Galston/Berrilee/Arcadia/Forest Glen/Glenorie/Berowra Heights bushland fringe) in Hornsby
  • Single and two-storey designs available
  • 6-year structural warranty
  • Free site assessment — near Hornsby station
Buildana knockdown-rebuild in Hornsby near Westfield Hornsby + Hornsby Hospital + Florence Street
OA

Reviewed by Oliver Alameri

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

Why Knockdown Rebuild in Hornsby?

Hornsby is the LGA's CBD and rail interchange — Westfield Hornsby, Hornsby Hospital and the Hornsby CBD high-rise zone front the station. R3/R4 redevelopment around the CBD with surrounding 1960s–1990s brick veneer residential streets on 600–900m² R2 blocks. Hawkesbury Sandstone bedrock with rock excavation typical.

Hornsby's mix of 1900s–1940s Federation heritage (Beecroft/Cheltenham/Pennant Hills/Wahroonga boundary) + 1960s–1990s brick (Cherrybrook/Asquith/Mount Colah/Mount Kuring-gai) + 2010s+ R3/R4 redevelopment around Hornsby/Asquith/Waitara stations-era housing on 700–1,200m² typical (Hornsby/Asquith/Pennant Hills/Beecroft/Wahroonga boundary/Cherrybrook); 1–5ha acreage (Galston/Berrilee/Arcadia/Forest Glen/Glenorie/Berowra Heights bushland fringe) blocks creates strong opportunity for property improvement. Median prices of $1.8M–$2.6M Hornsby/Asquith/Mount Colah; $2.4M–$3.6M Cherrybrook/Beecroft/Pennant Hills; $3.0M–$8.0M+ Galston/Arcadia acreage support quality build investment. Hornsby benefits from Hornsby station on the doorstep — walkable rail access lifts both rental demand and property values. 1900s–1940s Federation heritage (Beecroft/Cheltenham/Pennant Hills/Wahroonga boundary) + 1960s–1990s brick (Cherrybrook/Asquith/Mount Colah/Mount Kuring-gai) + 2010s+ R3/R4 redevelopment around Hornsby/Asquith/Waitara stations-era housing stock across Hornsby is prime for knockdown rebuild — replacing dated layouts and materials with modern, NCC-compliant homes that maximise block potential. Soil conditions in Hornsby (Class Hawkesbury Sandstone bedrock predominant (saw-cutting, rock-anchoring $30K–$120K above standard substructure) / Class M Wianamatta Shale on Cherrybrook/Beecroft ridges / bushfire-prone land BAL-12.5 to BAL-FZ on virtually all bushland-fringe (most of the LGA), moderately to highly reactive) are factored into every Buildana foundation design.

Knockdown-rebuild builder in Hornsby — key facts

Suburb
Hornsby, NSW 2077
Council / LGA
Hornsby Shire Council (Hornsby Shire)
Primary zoning
R2 / R3 / R4 mixed (Hornsby CBD)
Typical lot size
700–1,200m² typical (Hornsby/Asquith/Pennant Hills/Beecroft/Wahroonga boundary/Cherrybrook); 1–5ha acreage (Galston/Berrilee/Arcadia/Forest Glen/Glenorie/Berowra Heights bushland fringe)
Soil class
Class Hawkesbury Sandstone bedrock predominant (saw-cutting, rock-anchoring $30K–$120K above standard substructure) / Class M Wianamatta Shale on Cherrybrook/Beecroft ridges / bushfire-prone land BAL-12.5 to BAL-FZ on virtually all bushland-fringe (most of the LGA)
Median house price
$1.8M–$2.6M Hornsby/Asquith/Mount Colah; $2.4M–$3.6M Cherrybrook/Beecroft/Pennant Hills; $3.0M–$8.0M+ Galston/Arcadia acreage
Home era
1900s–1940s Federation heritage (Beecroft/Cheltenham/Pennant Hills/Wahroonga boundary) + 1960s–1990s brick (Cherrybrook/Asquith/Mount Colah/Mount Kuring-gai) + 2010s+ R3/R4 redevelopment around Hornsby/Asquith/Waitara stations
Typical price range
$450,000 – $1,200,000+
Typical timeline
14–22 months including demolition
Approval pathway
CDC where eligible or DA for complex sites

Building in Hornsby — Local Context

Foundations & Slab Design for Hornsby

Hornsby's ground is moderately to highly reactive clay (Class Hawkesbury Sandstone bedrock predominant (saw-cutting, rock-anchoring $30K–$120K above standard substructure) / Class M Wianamatta Shale on Cherrybrook/Beecroft ridges / bushfire-prone land BAL-12.5 to BAL-FZ on virtually all bushland-fringe (most of the LGA)). On a 700–1,200m² typical (Hornsby/Asquith/Pennant Hills/Beecroft/Wahroonga boundary/Cherrybrook); 1–5ha acreage (Galston/Berrilee/Arcadia/Forest Glen/Glenorie/Berowra Heights bushland fringe) block, that translates to engineered slab work in the $24,000–$42,000 bracket for a rebuild. Double-check any quote that doesn't itemise the slab — 'slab as per engineering' usually means the builder will hit you with a variation once the soil report comes back. We commission the geotech upfront, before pricing, so the cost in your contract reflects what your block actually needs. If your neighbour's home shows movement cracks above architraves or below window sills, that's a signal worth knowing before you finalise design — Buildana's site assessment looks at adjacent stock too.

Planning Controls in Hornsby

Hornsby is zoned R2 / R3 / R4 mixed (Hornsby CBD) with R3 Medium Density pockets. Hornsby Shire Council controls FSR, height limits (typically 8.5–9m), site coverage, landscaped area minimums, and setbacks. For a rebuild, the binding constraints on most 700–1,200m² typical (Hornsby/Asquith/Pennant Hills/Beecroft/Wahroonga boundary/Cherrybrook); 1–5ha acreage (Galston/Berrilee/Arcadia/Forest Glen/Glenorie/Berowra Heights bushland fringe) 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.

Hornsby Build Economics

Hornsby sits in the $1.8M–$2.6M Hornsby/Asquith/Mount Colah; $2.4M–$3.6M Cherrybrook/Beecroft/Pennant Hills; $3.0M–$8.0M+ Galston/Arcadia acreage price band, which is the framing for any knockdown rebuild decision. On a 700–1,200m² typical (Hornsby/Asquith/Pennant Hills/Beecroft/Wahroonga boundary/Cherrybrook); 1–5ha acreage (Galston/Berrilee/Arcadia/Forest Glen/Glenorie/Berowra Heights bushland fringe) block here, the build-versus-buy maths usually favours knockdown rebuild on stock from before 1985 — replacement value typically beats deep renovation. Free Buildana feasibility runs the numbers against your actual block before any commitment.

Designing for the Hornsby Streetscape

Hornsby's housing stock is predominantly from the 1900s–1940s Federation heritage (Beecroft/Cheltenham/Pennant Hills/Wahroonga boundary) + 1960s–1990s brick (Cherrybrook/Asquith/Mount Colah/Mount Kuring-gai) + 2010s+ R3/R4 redevelopment around Hornsby/Asquith/Waitara stations.. The local anchor is Westfield Hornsby + Hornsby Hospital + Florence Street. For a knockdown rebuild, the streetscape question matters more than most builders admit — a brand-new double-storey on a street of single-storey 1900s–1940s Federation heritage (Beecroft/Cheltenham/Pennant Hills/Wahroonga boundary) + 1960s–1990s brick (Cherrybrook/Asquith/Mount Colah/Mount Kuring-gai) + 2010s+ R3/R4 redevelopment around Hornsby/Asquith/Waitara stations 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.

What Recent Approvals Show

Hornsby Shire Council's recent decisions for Rebuilds in Hornsby reveal a clear pattern — applications that demonstrate genuine understanding of Hornsby Shire Council's DCP — not just the State controls — progress materially faster. Sloppy lodgement adds 4-8 weeks of round-trip; clean lodgement doesn't.

Builder's Take on Hornsby

One-contract KDR in Hornsby vs two-contractor (demo + builder separately): two-contractor looks cheaper on paper but the site risk transfers to you between the crews. Old footings, buried tanks, boundary disputes — all your problem. Buildana's single contract keeps the risk with the contractor.

KDR maths in Hornsby usually wins against deep renovation once renovation costs cross $300K. Below that, renovation is competitive. Above it, you're paying renovation pricing for a home that's still structurally 1970s. New build gives you 6-year warranty, NCC 2025 performance, and a genuine reset on property value.

Hornsby vs Nearby Suburbs

Hornsby vs nearby suburbs — key metrics for knocking down and rebuilding.

SuburbMedian PriceTypical LotSoil ClassEraStation
Hornsby2077this suburb$1.8M–$2.6M Hornsby/Asquith/Mount Colah; $2.4M–$3.6M Cherrybrook/Beecroft/Pennant Hills; $3.0M–$8.0M+ Galston/Arcadia acreage700–1,200m² typical (Hornsby/Asquith/Pennant Hills/Beecroft/Wahroonga boundary/Cherrybrook); 1–5ha acreage (Galston/Berrilee/Arcadia/Forest Glen/Glenorie/Berowra Heights bushland fringe)Class Hawkesbury Sandstone bedrock predominant (saw-cutting, rock-anchoring $30K–$120K above standard substructure) / Class M Wianamatta Shale on Cherrybrook/Beecroft ridges / bushfire-prone land BAL-12.5 to BAL-FZ on virtually all bushland-fringe (most of the LGA)1900s–1940s Federation heritage (Beecroft/Cheltenham/Pennant Hills/Wahroonga boundary) + 1960s–1990s brick (Cherrybrook/Asquith/Mount Colah/Mount Kuring-gai) + 2010s+ R3/R4 redevelopment around Hornsby/Asquith/Waitara stationsHornsby
Asquith2077$1.8M–$2.6M Hornsby/Asquith/Mount Colah; $2.4M–$3.6M Cherrybrook/Beecroft/Pennant Hills; $3.0M–$8.0M+ Galston/Arcadia acreage700–1,200m² typical (Hornsby/Asquith/Pennant Hills/Beecroft/Wahroonga boundary/Cherrybrook); 1–5ha acreage (Galston/Berrilee/Arcadia/Forest Glen/Glenorie/Berowra Heights bushland fringe)Class Hawkesbury Sandstone bedrock predominant (saw-cutting, rock-anchoring $30K–$120K above standard substructure) / Class M Wianamatta Shale on Cherrybrook/Beecroft ridges / bushfire-prone land BAL-12.5 to BAL-FZ on virtually all bushland-fringe (most of the LGA)1900s–1940s Federation heritage (Beecroft/Cheltenham/Pennant Hills/Wahroonga boundary) + 1960s–1990s brick (Cherrybrook/Asquith/Mount Colah/Mount Kuring-gai) + 2010s+ R3/R4 redevelopment around Hornsby/Asquith/Waitara stationsAsquith
Wahroonga2076$3.0M–$4.6M800–1,500m²Class M1920s–1960s (heavy heritage stock)Wahroonga
Mount Colah2079$1.8M–$2.6M Hornsby/Asquith/Mount Colah; $2.4M–$3.6M Cherrybrook/Beecroft/Pennant Hills; $3.0M–$8.0M+ Galston/Arcadia acreage700–1,000m²Class Hawkesbury Sandstone bedrock predominant (saw-cutting, rock-anchoring $30K–$120K above standard substructure) / Class M Wianamatta Shale on Cherrybrook/Beecroft ridges / bushfire-prone land BAL-12.5 to BAL-FZ on virtually all bushland-fringe (most of the LGA)1900s–1940s Federation heritage (Beecroft/Cheltenham/Pennant Hills/Wahroonga boundary) + 1960s–1990s brick (Cherrybrook/Asquith/Mount Colah/Mount Kuring-gai) + 2010s+ R3/R4 redevelopment around Hornsby/Asquith/Waitara stationsMount Colah

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.

Cost Guide

ItemEstimated Range
Clean demolition + standard rebuild$480,000 – $750,000
Asbestos-affected demolition + rebuild$510,000 – $800,000
Sloping site + cut/fill + rebuild$560,000 – $900,000
Heritage-affected or complex site$600,000 – $1,100,000
Premium finishes & architectural design$950,000+

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

How It Works

From First Call to Final Key

KDR starts with an honest look at the existing house. Sometimes it's worth keeping. Most Hornsby homes from the 1900s–1940s Federation heritage (Beecroft/Cheltenham/Pennant Hills/Wahroonga boundary) + 1960s–1990s brick (Cherrybrook/Asquith/Mount Colah/Mount Kuring-gai) + 2010s+ R3/R4 redevelopment around Hornsby/Asquith/Waitara stations — especially fibro and brick-veneer — are beyond the point where renovation makes sense. We tell you straight.

Demolition is pre-approved to run parallel with rebuild design. Asbestos cleared, services abolished, site stripped in a single mobilisation. Geotech reconfirms Class Hawkesbury Sandstone bedrock predominant (saw-cutting, rock-anchoring $30K–$120K above standard substructure) / Class M Wianamatta Shale on Cherrybrook/Beecroft ridges / bushfire-prone land BAL-12.5 to BAL-FZ on virtually all bushland-fringe (most of the LGA) soil with the old house gone.

New house goes up on the same footprint or a better one, whichever serves the block. Modern NCC envelope, better orientation, fit-for-purpose room sizes. The suburb stays the same; the house finally fits it.

Final handover: new OC, six-year structural warranty, all the documentation on your Hornsby block you'd get on a greenfield build. The only difference is you still live in the street you chose.

New home on the same land — keep the suburb, keep the schools, keep the street
Faster than selling and rebuying in Hornsby — and cheaper than two stamp duties
Single contract covers demolition and rebuild — one contractor, one timeline
Fixed-price inclusive of demolition, rubbish removal, asbestos — no surprise invoices
Modern NCC 2025 performance — 7-star NatHERS, BASIX 2025 compliant from day one
700–1,200m² typical (Hornsby/Asquith/Pennant Hills/Beecroft/Wahroonga boundary/Cherrybrook); 1–5ha acreage (Galston/Berrilee/Arcadia/Forest Glen/Glenorie/Berowra Heights bushland fringe) block replanned for how you live now, not how 1970s Sydney lived
6-year structural warranty on the new home — same as a greenfield build
Property value reset to new-build benchmark in the suburb

Our Team

OA

Oliver Alameri

Founder / Director / Builder · MPropDev · PhD Student

AA

Ahmad Alameri

Accounts Manager

CW

Claire Wendell

Project Manager

Estimate Your Build Cost

Use our free calculator to get an instant cost estimate for your project

Open Calculator →

Ready to take the next step?

Free consultation — no obligation, no pressure.

Frequently Asked Questions

Google Reviews
5.0
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

See all reviews on Google
Areas We Serve

We Build Across Sydney

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.

Demolish and Rebuild in Hornsby

Free KDR site assessment for Hornsby 2077. We'll assess your block, estimate cost, and provide a fixed-price budget.

Start Your Project