How much does a garage conversion cost in Sydney?

A typical 2026 Sydney garage conversion runs $25,000–$60,000 depending on slab condition, insulation, lining, flooring, windows, electrical and compliance work. A simple study-to-bedroom conversion can be $5,000–$20,000, while attic conversions with stairs and structural work commonly run $50,000–$120,000+.

What makes a converted room a legal bedroom in NSW?

Habitable rooms need to meet Building Code requirements — typically a minimum 2.4m ceiling over most of the room, natural light and ventilation in proportion to floor area, and safe egress. Council approval or a complying development pathway may be required depending on the conversion; a licensed builder should confirm the pathway before work starts.

Cost guide

Room conversion costs in Sydney: garage, study and attic

Guides5 min read

Interior carpentry and renovation by Aurum Built

The cheapest extra room is the one already under your roof. Converting existing space — a garage, study, attic or sunroom — costs a fraction of an extension, and done to compliance it genuinely counts when the property is valued or sold. This is core territory for us as a licensed Sydney builder (Licence 481876C): structural carpentry, linings, compliance and finish.

Typical Sydney ranges (2026)

Study or sunroom to bedroom: $5,000–$20,000 — window/egress compliance, wardrobe, electrical, flooring and finish.
Garage conversion: $25,000–$60,000 — slab treatment, insulation, lining, windows, door infill, electrical, flooring, compliance.
Attic conversion: $50,000–$120,000+ — stairs, structural work, dormers or skylights, insulation and lining.
Adding an ensuite to the new room: add bathroom money — see our bathroom cost guide.

What makes it a legal bedroom

A bedroom isn't a marketing term — it's a compliance standard. Habitable rooms need (broadly) a 2.4 m ceiling over most of the floor, natural light and ventilation proportionate to floor area, and safe egress. Depending on the conversion, council approval or a complying-development pathway may apply. Get the pathway confirmed before work starts — an uncertified "bedroom" can be flagged at sale and subtract the very value you built it for.

Why conversions punch above their weight

Moving from two bedrooms to three shifts your property into a different buyer bracket, and a conversion achieves it without foundations, roofing or the months an extension takes. It's one of the highest return-per-dollar moves in renovation — we run the numbers in our guide to renovation ROI and property value. See our services for how we handle the carpentry and build side.

Extensions add space; conversions add value. Start with the space you've already paid for.

Cost guide Conversions Sydney

Got a garage or study doing nothing?

Tell us about the space and we'll scope the conversion — compliance pathway included.

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