Roseville Home Extension Builder — Live In, Build On
Buildana extends homes across Roseville 2069 while you stay in place. 1920s–1960s (heavy heritage stock)-era structure, Ku-ring-gai Council rules, weatherproofing during build — all managed locally from Fairfield.
HIA Member
MBA NSW0476 300 300Quick Answer
A home extension in Roseville 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.
Roseville Home Extensions & Additions
A home extension in Roseville starts with heritage, because Ku-ring-gai Council watches this suburb's Federation and Californian Bungalow stock carefully and demolition scrutiny is heavier here than further up the line. The good news for extenders is that additions read very differently to demolition: keep the character frontage, work behind and above it, and the path is far smoother. Premium blocks of 750 to 1,200m² give ample room to do exactly that.
The bungalow stock is a gift structurally, since much of it is solid brick that carries a first-floor addition on its original walls when the design respects the roofline. Where owners prefer to stay level, the generous blocks take a rear wing easily. The village around Roseville Cinema and the Lane Cove River framing the southern boundary are exactly the character owners extend to keep.
What I would check first on your Roseville house: the heritage status of the frontage, whether the walls carry a first floor, and the rear yard depth. Those set the direction.
We build these fixed-price, licence HBL 487805C. Let us check your street's controls before you design.
Buildana manages the complete home extension process in Roseville — 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 Roseville 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 Roseville station
Reviewed by Oliver Alameri
Licensed Builder (NSW 487805C) · Master of Property Development · PhD Student · Building across Western Sydney since 2010
Heritage first, then the build
Ku-ring-gai Council watches the Federation and Californian Bungalow stock carefully, and demolition scrutiny is heavier here than further up the line.
Additions read very differently to demolition: keep the character frontage, work behind and above it, and the path is far smoother. Premium 750 to 1,200m² blocks give room to do exactly that.
The bungalow is a gift
Much of the bungalow stock is solid brick that carries a first-floor addition on its original walls when the design respects the roofline.
Where owners prefer to stay level, the generous blocks take a rear wing easily, opening onto the garden settings the suburb is known for.
Home extension builder in Roseville — key facts
- Suburb
- Roseville, NSW 2069
- Council / LGA
- Ku-ring-gai Council (Ku-ring-gai)
- Primary zoning
- R2 Low Density
- Typical lot size
- 750–1,200m²
- Soil class
- Class M
- Median house price
- $2.8M–$4.2M
- 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.
Cost Guide
| Item | Estimated Range |
|---|---|
| Single-room addition (bedroom/study) | $77,000 – $180,000 |
| Kitchen/living extension | $190,000 – $450,000 |
| Master suite + ensuite addition | $170,000 – $360,000 |
| Second storey (full or partial) | $360,000 – $700,000 |
| Multi-room ground floor wrap | $450,000 – $770,000 |
Prices are indicative for Western Sydney (2025). Actual costs depend on site, specifications, and approvals.
How It Works
From First Call to Final Key
Extension feasibility comes down to two things: what the existing structure can carry, and what Ku-ring-gai Council will let you build. We assess both at the consultation — no point designing for a second storey if the slab can't take the load.
⏱Extension designed to integrate with your existing Roseville home — matching roof lines, materials, and flow between old and new sections. Floor plans, elevations, and 3D renders.
⏱All approval documentation prepared: structural drawings, BASIX, shadow analysis, stormwater, and statement of environmental effects (if DA). Lodged and managed through to Construction Certificate.
⏱Extension construction takes 3–6 months on average. Footings excavated and poured to match existing depth on Class M soil, frame stand, roof tie-in (most weather-critical phase), lock-up, then internal fit-out at the same standard as the existing house.
⏱Defect-free inspection, OC issued, 6-year warranty on all new work. Junction between old and new sections waterproofed and warranted. Maintenance guide covers care of new and existing areas.
⏱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
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