Home Extension Builder Sylvania Waters — From $150K Fixed Price
Fixed-price home extensions in Sylvania Waters 2224. Rear extension $150K–$300K, second storey $300K–$500K. Sutherland Shire Council approvals managed. Free site consult.
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MBA NSW0476 300 300Quick Answer
A home extension in Sylvania Waters 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.
Second-Storey & Rear Additions in Sylvania Waters
A home extension in Sylvania Waters is a waterfront engineering job. This canal-frontage suburb runs 1970s to 1990s homes with deep-water moorings on the Gwawley Bay and Georges River canal system, on 600 to 1,000m² blocks, and any addition near the water is built to marine standard: N40 marine-grade concrete and 316 stainless are universal here because the canal environment destroys ordinary materials. At a $2.4M to $5.5M-plus median, doing it to that spec is the only sensible approach.
Canal-frontage work carries its own approvals. The Foreshore Building Line caps how far any structure can push toward the water, and a Crown Lands referral applies to works near the canal edge, so those constraints get designed in before anything else. The premium yacht and cruiser owner demographic here expects an addition that respects the waterfront setting rather than fighting it.
What I would check first on your Sylvania Waters block: the Foreshore Building Line, the Crown Lands referral on canal-edge works, and the marine-grade spec the environment demands. Those decide the design.
We build these fixed-price, licence HBL 487805C. Show us your frontage and we will design to it.
Buildana manages the complete home extension process in Sylvania Waters — 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 Sylvania Waters from $150K
- Sutherland Shire Council DA and CDC approvals managed
- Ground floor, rear and second-storey additions
- Hawkesbury Sandstone bedrock — structural engineering included
- 1970s–1990s + premium contemporary waterfront-era homes assessed for extension suitability
- Connect new to existing — clean, matched finish
- 6-year structural warranty
- Free design consultation — near Miranda (3 km) station
Reviewed by Oliver Alameri
Licensed Builder (NSW 487805C) · Master of Property Development · PhD Student · Building across Western Sydney since 2010
Built to marine standard
This canal-frontage suburb runs 1970s to 1990s homes with deep-water moorings on the Gwawley Bay and Georges River canal system, on 600 to 1,000m² blocks.
Any addition near the water is built to marine standard: N40 marine-grade concrete and 316 stainless are universal, because the canal environment destroys ordinary materials.
Foreshore approvals
The Foreshore Building Line caps how far any structure can push toward the water, and a Crown Lands referral applies to works near the canal edge, so those constraints get designed in first.
At a $2.4M to $5.5M-plus median, the premium waterfront demographic expects an addition that respects the setting rather than fighting it.
Home extension builder in Sylvania Waters — key facts
- Suburb
- Sylvania Waters, NSW 2224
- Council / LGA
- Sutherland Shire Council (Sutherland Shire)
- Primary zoning
- R2 Low Density predominant
- Typical lot size
- 600–1,000m²
- Soil class
- Hawkesbury Sandstone bedrock
- Median house price
- $2.4M–$5.5M+ (canal frontage)
- Home era
- 1970s–1990s + premium contemporary waterfront
- 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. Free consultation at your Sylvania Waters home. We inspect the existing structure, check Sutherland Shire Council's controls, measure available space, and discuss what you need. You get a clear scope, budget range, and timeline before committing. Two design moves are usually on the table: match the existing house so the extension reads as original, or contrast with it so the new section is clearly modern. Both work — choice is aesthetic, and we'll show 3D renders of both before you commit.
⏱The Sylvania Waters construction phase. Fixed price, programmed, supervised. CDC (10–15 business days) or DA through Sutherland Shire Council depending on scope. Structural engineering, BASIX, and all documentation prepared and lodged. Construction Certificate obtained. Construction phase connects new to existing — footings, frame, roof tie-in, waterproofing at junction, internal fit-out and external finish. Staged works minimise disruption to your daily routine in Sylvania Waters.
⏱The job isn't done when the site's clean; it's done when you have keys, certificates and warranties. Final inspection focuses on the integration: paint blend, flooring transitions, ceiling height, junction waterproofing, sound transmission. The extension shouldn't feel bolted on — it should feel like the house was always meant to be this size.
⏱Quality Promise
Every Buildana home extension in Sylvania Waters is delivered under a fixed-price contract — from design consultation through to defect-free handover.
Cost Guide
| Item | Estimated Range |
|---|---|
| Small rear extension (up to 30m²) | $90,000 – $180,000 |
| Medium rear/side extension (30–60m²) | $180,000 – $320,000 |
| Large ground-floor extension (60–100m²) | $320,000 – $500,000 |
| Second-storey addition (60–120m²) | $280,000 – $550,000 |
| Wrap-around (ground + 1st floor) | $500,000+ |
| 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
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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.
Sylvania Waters Extension — Free Consultation
Free design consultation for Sylvania Waters 2224. We'll assess your home, design the extension, and provide a fixed-price quote.
Start Your ProjectMore in Sylvania Waters
Other Buildana services in Sylvania Waters
Costs, approval pathway and fixed-price contract detail for every other build type we deliver in Sylvania Waters 2224. Sutherland Shire Council regulations and local controls are covered on each page.