Home Extension Glenhaven — Design, Approval, Structural, Build
Full-service extensions in Glenhaven 2156: structural survey of existing 1970s–2000s home, design, The Hills Shire Council approval, engineering, weatherproofed construction, matched finish to original dwelling.
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MBA NSW0476 300 300Quick Answer
A home extension in Glenhaven costs $150,000–$600,000+. Rear extension from $150K, second-storey addition from $300K. Buildana manages design, The Hills Shire Council approvals, and construction under one fixed-price contract.
Home Extension Builder in Glenhaven
A home extension in Glenhaven uses the semi-rural room — 1,500 to 4,000m² blocks where the 1970s-2000s homes take generous wings without touching a setback.
The bush-edge lots get the BAL assessment, the shale junctions are engineered, and the leafy prestige market rewards additions done to scale.
At the $2.5M to $5M+ median, the wing beats surrendering a block this size to move.
We build these fixed-price, licence HBL 487805C. Ask us to measure what your block can hold.
Buildana manages the complete home extension process in Glenhaven — 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 Glenhaven from $150K
- The Hills Shire Council DA and CDC approvals managed
- Ground floor, rear and second-storey additions
- M — structural engineering included
- 1970s–2000s-era homes assessed for extension suitability
- Connect new to existing — clean, matched finish
- 6-year structural warranty
- Free design consultation — near Bus to Castle Hill Metro (4 km) station
Reviewed by Oliver Alameri
Licensed Builder (NSW 487805C) · Master of Property Development · PhD Student · Building across Western Sydney since 2010
Room nobody surrenders
Glenhaven's quarter-hectare-plus blocks are the reason owners stay — and the wing uses them: pavilion living, parents' suites, entertaining domains that suburban blocks cannot fit.
The 1970s-2000s stock takes the additions confidently once the junctions are engineered.
Bush edges assessed
BAL ratings apply on the vegetated boundaries and shape the external materials where they do.
That assessment sets the materials and sits in the fixed price from the outset.
Home extension builder in Glenhaven — key facts
- Suburb
- Glenhaven, NSW 2156
- Council / LGA
- The Hills Shire Council (The Hills)
- Primary zoning
- R2 Low
- Typical lot size
- 1,500–4,000m²
- Soil class
- M
- Median house price
- $2.5M–$5M+
- Home era
- 1970s–2000s
- 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.
Cost Guide
| Item | Estimated Range |
|---|---|
| Simple rear extension (single wall removal, no roof change) | $97,000 – $220,000 |
| Moderate extension (multiple openings, roof extended) | $220,000 – $410,000 |
| Complex extension (structural steel portals, re-roofing) | $410,000 – $650,000 |
| Second-storey tie-in (existing house re-engineered) | $380,000 – $700,000 |
Prices are indicative for Western Sydney (2025). Actual costs depend on site, specifications, and approvals.
How It Works
From First Call to Final Key
The first job on an extension is finding out what you're extending onto. Glenhaven homes from the 1970s–2000s were built to different standards — we open walls, check footings, verify load paths. The existing house has to carry the new work.
⏱Design follows the existing roof. A bad extension looks like a bolt-on; a good one reads as original. Matched brickwork or contrasting render (whichever the architecture calls for), tied-in roofline, continuous flooring where it should be continuous.
⏱Construction happens while you live in the house. That means weatherproofing every night, staging the works so kitchens and bathrooms don't disappear on the same week, and keeping the site clean of debris that doesn't belong in a family home.
⏱Finish is seamless. Paint match, floor match, roofline match, brick match where possible. The only way to tell the extension is new is the date on the plans.
⏱Our Team
Oliver Alameri
Founder / Director / Builder · MPropDev · PhD Student
Ahmad Alameri
Accounts Manager
Claire Wendell
Project Manager
Estimate Your Build Cost
Use our free calculator to get an instant cost estimate for your project
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
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.
Last updated: 1 April 2026
Add Space to Your Glenhaven Home
Free design consultation for Glenhaven 2156. We'll assess your home, design the extension, and provide a fixed-price quote.
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Other Buildana services in Glenhaven
Costs, approval pathway and fixed-price contract detail for every other build type we deliver in Glenhaven 2156. The Hills Shire Council regulations and local controls are covered on each page.