Renovation & Extension Architects Sydney | giantA
Home renovations, ground-floor extensions and second-storey additions across Sydney. Design, approvals and builder-ready documentation.
Contact UsRenovation vs extension — which do you need?
Renovation: You keep the same footprint but change the layout, finishes or function. Typically exempt from approval if internal only.
Extension: You add new floor area. Always requires approval — CDC if code-compliant, DA if not.
Second storey: The most complex option — needs structural engineering, overshadowing analysis, and often a DA. But it can double your floor area without losing garden.
Extension costs per m² in Sydney
| Type | Cost per m² | Typical total (30 m²) |
|---|---|---|
| Single-storey ground-floor | $3,000 – $5,000 | $90,000 – $150,000 |
| Second-storey addition | $3,500 – $6,000 | $105,000 – $180,000 |
| Architecture + approvals | — | $8,000 – $20,000 |
| CDC approval (if compliant) | — | 2–4 weeks |
| DA approval (if not compliant) | — | 6–16 weeks |
Our renovation and extension process
- Site visit & brief: we measure your existing home, identify structural constraints, and understand your needs
- Concept design: options for layout, materials and budget
- Approvals: CDC or DA documentation, BASIX, structural engineering
- Construction-ready docs: builder tender package, specifications, contract administration (optional)
Frequently Asked Questions
Do I need approval for a home renovation in NSW?
Minor renovations (kitchen, bathroom, internal walls) that don't change the external envelope or load-bearing structure are usually exempt development under the State Environmental Planning Policy. Additions, second-storey extensions, and structural changes typically need a CDC or DA.
Can I add a second storey to my house in Sydney?
Yes, if your LEP and DCP allow it. Most R2 zones in Sydney permit two-storey dwellings (8.5–9.5 m height). Key constraints: overshadowing of neighbours, privacy, and structural capacity of existing footings. A structural engineer assessment is required.
How much does a home extension cost in Sydney?
Single-storey extensions: $3,000–$5,000 per m² (typical Sydney construction cost). Second-storey additions: $3,500–$6,000 per m². A 30 m² ground-floor extension typically costs $90,000–$150,000. Architectural and approval costs add $8,000–$20,000.
What is the difference between renovation and extension?
A renovation modifies existing spaces (new kitchen, bathroom, reconfiguration). An extension adds new floor area (extra bedroom, larger living room, second storey). Extensions always need approval; renovations may be exempt if internal only.
How long does a renovation or extension take?
Minor renovation (kitchen/bathroom): 4–8 weeks. Single-storey extension: 3–5 months (design + approval) + 3–6 months construction. Second-storey addition: 4–6 months (design + approval) + 6–12 months construction.
Can an architect help me stay within budget?
Yes — by designing for standard construction methods, avoiding custom structural solutions, and specifying materials within your budget. We provide a detailed cost estimate at concept stage so there are no surprises during construction.
Ready to discuss your project?
Talk to our team about your site, timeline and approval pathway. We respond within one business day.
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