Home Extension Gymea — Design, Approval, Structural, Build
Full-service extensions in Gymea 2227: structural survey of existing 1960s–1990s fibro/brick veneer predominant + 1990s–2010s brick (Menai/Bangor/Illawong/Alfords Point) + 2010s+ premium contemporary (Cronulla beachside/foreshore) home, design, Sutherland Shire Council approval, engineering, weatherproofed construction, matched finish to original dwelling.
HIA Member
MBA NSW0476 300 300Quick Answer
A home extension in Gymea costs $150,000–$600,000+. Rear extension from $150K, second-storey addition from $300K. Buildana manages design, Sutherland Shire Council approvals, and construction under one fixed-price contract.
Gymea Home Extensions — Fixed Price
A home extension in Gymea grows the Shire family home — 1960s-1990s fibro and brick veneer on 550 to 800m² blocks where the wing adds the space the originals rationed and the village strip stays on foot.
The fibro gets the licensed strip-out before anything else, the junctions are engineered, and the rail keeps the position practical.
At the $1.4M to $2.2M mid-tier, the wing beats the friction of upsizing further into the Shire.
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 Gymea — 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 Gymea from $150K
- Sutherland Shire Council DA and CDC approvals managed
- Ground floor, rear and second-storey additions
- Hawkesbury Sandstone bedrock — structural engineering included
- 1960s–1990s fibro/brick veneer predominant + 1990s–2010s brick (Menai/Bangor/Illawong/Alfords Point) + 2010s+ premium contemporary (Cronulla beachside/foreshore)-era homes assessed for extension suitability
- Connect new to existing — clean, matched finish
- 6-year structural warranty
- Free design consultation — near Gymea station
Reviewed by Oliver Alameri
Licensed Builder (NSW 487805C) · Master of Property Development · PhD Student · Building across Western Sydney since 2010
The village holds them here
Gymea's strip and rail are why families stay — and the rear wing adds the second living and bedrooms without giving either up.
The 1960s-1990s stock takes the additions confidently once it is engineered.
Fibro handled first
Where the original is fibro, the licensed asbestos strip-out leads the job — priced upfront rather than discovered mid-build.
The junctions are engineered where the new meets the old.
Home extension builder in Gymea — key facts
- Suburb
- Gymea, NSW 2227
- Council / LGA
- Sutherland Shire Council (Sutherland Shire)
- Primary zoning
- R2 Low Density predominant
- Typical lot size
- 550–800m² typical; 600–1,000m² premium beachside/foreshore (Cronulla/Burraneer/Lilli Pilli/Yowie Bay/Caringbah South/Sylvania Waters); 700–2,000m² bushland-fringe (Bundeena, Maianbar, Bangor, Menai)
- Soil class
- Hawkesbury Sandstone bedrock
- Median house price
- $1.4M–$2.2M mid-tier; $1.8M–$3.8M foreshore; $2.5M–$6.0M+ Cronulla/Burraneer/Lilli Pilli/Caringbah South premium beachside
- Home era
- 1960s–1990s fibro/brick veneer predominant + 1990s–2010s brick
- 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
We assess your Gymea home — existing structure, block size (550–800m² typical; 600–1,000m² premium beachside/foreshore (Cronulla/Burraneer/Lilli Pilli/Yowie Bay/Caringbah South/Sylvania Waters); 700–2,000m² bushland-fringe (Bundeena, Maianbar, Bangor, Menai)), R2 Low Density predominant zoning, setbacks, FSR, and your space requirements. You'll know what's achievable before spending on detailed design.
⏱Design phase covers the extension layout, junction with existing structure, window and door placement, and external finish to match your Gymea home's streetscape. Multiple design options presented.
⏱Documentation pack covers structural engineering for the new footings sized to match existing depths on Class Hawkesbury Sandstone bedrock soil, BASIX 2025 compliance, shadow diagrams to neighbours' POS, hydraulic, and detailed sections through the wall-tie junction. Approval-grade, not concept-grade.
⏱Fixed-price construction of your extension. New footings engineered for Class Hawkesbury Sandstone bedrock soil, structural connection to existing home, frame, fit-out, and finishes. Weekly updates from your project manager.
⏱Handover documentation covers the new work specifically — OC for the extension, structural certs, BASIX certificate updates, and warranty for the new section plus the junction detailing. Existing house remains under whatever warranty position applied before.
⏱Quality Promise
We extend Gymea homes with a structural engineer on every job. Second storey, rear addition, multi-room — engineered and priced upfront.
Cost Guide
| Item | Estimated Range |
|---|---|
| Single-room addition (bedroom/study) | $60,000 – $140,000 |
| Kitchen/living extension | $150,000 – $350,000 |
| Master suite + ensuite addition | $130,000 – $280,000 |
| Second storey (full or partial) | $280,000 – $550,000 |
| Multi-room ground floor wrap | $350,000 – $600,000 |
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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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
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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.
Extend, Don't Move — Gymea
Free design consultation for Gymea 2227. We'll assess your home, design the extension, and provide a fixed-price quote.
Start Your ProjectMore in Gymea
Other Buildana services in Gymea
Costs, approval pathway and fixed-price contract detail for every other build type we deliver in Gymea 2227. Sutherland Shire Council regulations and local controls are covered on each page.