Last reviewed: August 2026
All three fit inside the same legal limit. A NSW granny flat is capped at 60m² of floor area, so a three bedroom is not a bigger building than a two bedroom, it is the same building with the space divided differently. That single fact drives every trade-off below.
Two bedroom is the most common choice in Sydney because it suits the widest range of tenants without cutting the living space to nothing.
The comparison
| 1 bedroom / studio | 2 bedroom | 3 bedroom | |
| Typical floor area | 35m² to 45m² | 50m² to 60m² | 60m², at the cap |
| Published 2026 Sydney cost | $120,000 to $145,000 | $145,000 to $200,000 | $175,000 to $220,000+ |
| Living space | Generous for the size | Comfortable | Tight |
| Tenant pool | Singles, couples, one parent | Couples, small families, sharers | Families, larger share groups |
| Best suited to | Elderly parent, teenager, home office | Most situations | Larger family under one roof |
| Cost per square metre | Highest | Middle | Lowest |
Why the smallest one costs the most per square metre
A granny flat has one kitchen, one bathroom and one set of service connections regardless of size. Those are the expensive parts, and they cost the same at 40m² as they do at 60m².
Spread across 40m², those fixed costs land heavily on every square metre. Spread across 60m², they land more lightly. So the studio has the lowest total price and the highest rate per square metre, and the difference between a 45m² and a 60m² build is often smaller than people expect, because the extra 15m² is only floor, walls and roof.
The practical consequence: if your block allows 60m² and your budget stretches, building smaller rarely saves as much as it costs you in usable space and rental appeal.
What each one actually gives you
One bedroom and studio
The most space per person. With only one bedroom to fit, the living area and kitchen can be properly sized rather than squeezed.
Works well for an elderly parent who wants their own front door, an adult child, a home office with a bathroom, or a single tenant. Where it struggles is resale and rental flexibility, because the tenant pool is narrower.
Two bedroom
The default for a reason. At 50m² to 60m² you can fit two real bedrooms, a bathroom, a kitchen and a living space that people will actually sit in.
It suits couples, a small family, two people sharing, or a parent with a child. That breadth is why it tends to hold rental appeal best across changing circumstances.
Three bedroom
Three bedrooms inside 60m² means every room gives something up. Bedrooms get smaller, the living area shrinks, and storage becomes a real design problem.
It is the right answer when the specific need is bedrooms, most often a larger family living together where the alternative is a much bigger and more expensive move. It is usually the wrong answer if the goal is rental yield, because the higher rent rarely offsets the reduced liveability and the narrower tenant appeal.
The layout trade-off at 60m²
Roughly how the space divides:
| Space | 1 bedroom | 2 bedroom | 3 bedroom |
| Bedrooms | 1 larger | 2 reasonable | 3 small |
| Living and dining | Generous | Adequate | Compressed |
| Kitchen | Full size | Full size | Often galley |
| Bathroom | Full | Full | Full, sometimes smaller |
| Storage | Comfortable | Adequate | Minimal |
The bathroom and kitchen cannot shrink much, because they have fixed minimum dimensions and fixed fittings. So every extra bedroom comes almost entirely out of the living area.
Which one should you build?
Work backwards from who is going to live in it.
- A family member for the long term. Build for their actual needs, not resale. One bedroom with a proper living space is often kinder than two cramped ones.
- Rental, and you want the widest tenant pool. Two bedroom.
- Rental, and you want the lowest entry cost. One bedroom or studio, accepting the narrower pool.
- A larger family under one roof. Three bedroom, going in with clear eyes about how tight 60m² is across three rooms.
- You are not sure yet. Two bedroom, because it suits the most situations and is the easiest to re-let or repurpose.
A note on rental returns
Be careful with return figures you see quoted online. Rent for a granny flat depends on the suburb, the finish, the parking, the privacy from the main house, and the current rental market. A yield calculated on someone else’s block in another suburb tells you very little about yours.
The reliable way to estimate it is to look at what comparable granny flats and small units are actually renting for in your suburb right now, then work from that number rather than a generic percentage.
Frequently asked questions
Can I build a granny flat bigger than 60m² in NSW?
Only if another planning instrument applying to your land permits a greater floor area. The Housing SEPP caps a secondary dwelling at 60m² as the default, and that applies on both the complying development and development application pathways.
Is a three bedroom granny flat worth it?
It depends on why you want it. If you genuinely need three bedrooms for family, it can be the right call. If the goal is rental income, the extra rent usually does not compensate for the cramped living space and the smaller pool of tenants who want three tiny bedrooms.
Does a two bedroom cost much more than a one bedroom?
Less than the size difference suggests. The kitchen, bathroom and connections are the same in both, so the extra cost is mostly floor, walls, roof and one more room’s worth of finishes.
What size granny flat rents best in Sydney?
Two bedroom tends to have the broadest appeal because it suits couples, sharers and small families. What rents best in your specific suburb is worth checking against current local listings rather than a general rule.
Do more bedrooms need more parking?
Parking requirements come from the planning controls applying to your land rather than from the bedroom count in a fixed way. The Housing SEPP treats the number of parking spaces on the site as a non-discretionary standard. Confirm the position for your block with your certifier.
See how the layouts actually work
Floor area on paper and floor area you can live in are different things. The easiest way to judge is to walk through the plans.
Browse the floor plans, or call BlueGum on 1300 060 651 to talk through which size suits your block and your situation.
BlueGum Granny Flats is a licensed NSW builder, licence number 247388C. Cost ranges are drawn from published 2026 Sydney market guides and are indicative only. They are not a quote. Rental figures should be checked against current listings in your suburb.
