Garage conversions in Canberra.
Convert an existing detached or attached garage into a fully habitable secondary residence. Re-floor, insulate, line, plumb, glaze, ventilate. The cheapest path to a Canberra granny flat where the slab, walls and roof are already there. $50K–$90K depending on size, existing condition and whether plumbing extension is needed.
Garage conversion — what it involves.
Why conversion = savings.
A new-build secondary residence has to pay for slab ($14K–$22K), frame and roof ($28K–$42K), and external cladding. A garage conversion has all of that already — you’re just paying for the fit-out conversion: insulation, internal framing, plumbing extension, electrical upgrade, windows, doors and finishes. That removes $40K–$60K from the build cost.
What gets done in a Canberra garage conversion.
- Slab: Existing concrete slab usually adequate — we level any high/low spots, install thermal break edging, lay R2.0 underfloor insulation board, top with 18mm engineered floor or polished concrete finish.
- Walls: Existing brick or block walls get a stud frame inside, R2.5 insulation, plasterboard line. External cladding refreshed if needed (or left if recently rendered).
- Roof: Existing roof structure typically OK but underside is uninsulated — we install R5.0 ceiling insulation and ceiling lining.
- Windows: Garage roller-door is removed and replaced with double-glazed sliding doors plus side windows. Garage side wall gets new double-glazed windows for natural light.
- Plumbing: Cold-water + hot-water + drain extension from main house (or new stub for detached garages). $5K–$15K depending on distance and trenching.
- Electrical: New circuit and sub-board, LED lighting, double power points to current code, single 3.5–5kW reverse-cycle split.
- Bathroom: Compact 2.0m × 1.7m fitout with hob-less shower, vanity, toilet.
- Kitchenette: Galley along one wall.
When conversion is the right call.
- Detached double garage with own access path (most common in Weston Creek, Tuggeranong, Belconnen 1970s subdivisions). 36–50m² floor area, perfect studio or 1-bed footprint.
- Attached double garage that’s under-used (Gungahlin, Belconnen modern homes). 35–40m², requires sound-proofed shared wall.
- Original brick garage with sound roof and slab. Structure is fundamentally OK so you’re not paying to rebuild.
- Owner has covered parking elsewhere (carport, second driveway) so loss of garage is acceptable.
When conversion is NOT the right call.
- Garage is too small (<25m²) — not enough envelope for a habitable build.
- Slab is cracked, uneven or below DPC level — cheaper to start fresh.
- Garage walls are timber-framed cladding rather than brick / block — insulation retrofit is awkward, may as well rebuild.
- No covered parking alternative on the block — loss of garage may hurt resale.
- EPSDD setback rules block the conversion (rare but happens with older non-conforming garages built before current Territory Plan).
Cost breakdown (typical 40m² detached-garage conversion).
- Slab prep, insulation, finish floor: $4,000–$6,000
- Internal stud frame + insulation + plasterboard: $9,000–$12,000
- Ceiling insulation + line: $4,000–$5,000
- Windows + sliding door (replacing roller door): $8,000–$11,000
- Plumbing extension + bathroom fitout: $14,000–$20,000
- Electrical + reverse-cycle split + LED: $10,000–$13,000
- Kitchenette: $7,000–$10,000
- EPSDD DA + NatHERS + certifier: $4,000–$7,000
- Total typical: $60,000–$84,000 turnkey
DA considerations.
A garage conversion to habitable use still requires a change-of-use DA through EPSDD. NatHERS 7-star applies to the converted space (same as new build). Some existing 1970s garages were built right on the side boundary — if the conversion increases the “habitable” footprint and there’s no current 1.5m setback, we may need a variation. We assess and confirm at site visit before quoting.
Where we work.
Free garage conversion consultation.
We’ll inspect the existing garage, advise on conversion vs rebuild honestly, and confirm change-of-use DA path.