Home Extension Builder Wahroonga — From $150K Fixed Price
Fixed-price home extensions in Wahroonga 2076. Rear extension $150K–$300K, second storey $300K–$500K. Ku-ring-gai Council approvals managed. Free site consult.
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MBA NSW0476 300 300Quick Answer
A home extension in Wahroonga costs $150,000–$600,000+. Rear extension from $150K, second-storey addition from $300K. Buildana manages design, Ku-ring-gai Council approvals, and construction under one fixed-price contract.
Wahroonga Home Extensions & Additions
A home extension in Wahroonga is really a story about staying put. Knox, Abbotsleigh and the public catchments hold families here, and when the house gets tight the answer is almost never to leave — it is to grow the heritage home instead, keeping the conserved Federation frontage and building a generous wing behind it on the 800 to 1,500m² blocks.
The heritage streets east of the highway are checked before design, so the approval is clear from the outset, and the pre-war fabric sees lead paint and asbestos handled under licence. The finish is built to the standard the pocket quietly demands.
At a $3.0M to $4.6M median, a wing done right carries the family for decades — more house, same school run, none of the cost of chasing size elsewhere.
We build these fixed-price, licence HBL 487805C. Get our extension scope, with the heritage position checked, before you commit.
Buildana manages the complete home extension process in Wahroonga — from design consultation and structural engineering through to DA or CDC approval, and fixed-price construction to handover. Extend your home without the stress.
Read our Home Extension Cost Guide 2026 or explore extension approval pathways in NSW.
- Home extensions in Wahroonga from $150K
- Ku-ring-gai Council DA and CDC approvals managed
- Ground floor, rear and second-storey additions
- Class M soil — structural engineering included
- 1920s–1960s (heavy heritage stock)-era homes assessed for extension suitability
- Connect new to existing — clean, matched finish
- 6-year structural warranty
- Free design consultation — near Wahroonga station
Reviewed by Oliver Alameri
Licensed Builder (NSW 487805C) · Master of Property Development · PhD Student · Building across Western Sydney since 2010
Nobody leaves the catchment
Wahroonga families extend because leaving means surrendering the schools — so the wing is built to carry decades: generous living behind the conserved Federation frontage, to the premium pocket's standard.
The 800 to 1,500m² blocks give the design genuine room to work with.
Heritage position and fabric handled
The heritage position east of the highway is checked before design, so the approval path is clear before you spend on drawings.
Pre-war hazards run as licensed processes, and every dollar of it is priced into the job from the outset.
Home extension builder in Wahroonga — key facts
- Suburb
- Wahroonga, NSW 2076
- Council / LGA
- Ku-ring-gai Council (Ku-ring-gai)
- Primary zoning
- R2 Low Density
- Typical lot size
- 800–1,500m²
- Soil class
- Class M
- Median house price
- $3.0M–$4.6M
- Home era
- 1920s–1960s
- Typical price range
- $150,000 – $600,000+
- Typical timeline
- 6–12 months design to handover
- Approval pathway
- CDC for most rear extensions, DA for second-storey
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
Everything that has to be right before we touch the ground. Walk through your Wahroonga home with our designer and structural engineer. We measure, photograph, and check the bones — footings, frame condition, roof structure. The cost estimate that follows is grounded in what we found, not a generic per-m² number. Our designer works with your existing home's layout — connecting new living areas to existing rooms, matching materials and roof pitch, and maximising natural light. You approve floor plans and 3D renders before we proceed.
⏱The Wahroonga construction phase. Fixed price, programmed, supervised. Most rear extensions in Wahroonga qualify for CDC — cleaner, faster, no neighbour notification. Second-storey additions typically need DA through Ku-ring-gai Council because of overshadowing and privacy assessments. We choose based on your design, not on what's easier to lodge. Extension built from new footings to completion — connecting structurally to your existing home. Class M soil design managed. Temporary weatherproofing maintains liveability where possible.
⏱The job isn't done when the site's clean; it's done when you have keys, certificates and warranties. Walk through the completed extension, confirm finishes, collect your OC. Six-year structural warranty covers all new work including the junction with your existing home. Maintenance guide provided.
⏱Quality Promise
Our Wahroonga home extensions connect old-to-new cleanly. Matched brickwork, tied roofline, no awkward transitions.
Cost Guide
| Item | Estimated Range |
|---|---|
| Small rear extension (up to 30m²) | $119,000 – $240,000 |
| Medium rear/side extension (30–60m²) | $240,000 – $420,000 |
| Large ground-floor extension (60–100m²) | $420,000 – $660,000 |
| Second-storey addition (60–120m²) | $370,000 – $730,000 |
| Wrap-around (ground + 1st floor) | $660,000+ |
| Structural engineering & tie-in | Included |
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
Estimate Your Build Cost
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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 April 2026
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Costs, approval pathway and fixed-price contract detail for every other build type we deliver in Wahroonga 2076. Ku-ring-gai Council regulations and local controls are covered on each page.