Suburb guide · 2041
Can I build a duplex or granny flat in Balmain?
Balmain sits in Inner West Council's area under Inner West Local Environmental Plan 2022. We ran 25 real Balmain addresses through the checker: the typical block is 247 m² with 7.6 m of frontage, 0 of the 25 could add a granny flat, and 19 could carry two separate homes today.
Thinking of building or selling in Balmain?
Tell us what you have in mind and we'll read your block and come back to you within a day. Free, no obligation.
The typical Balmain block
The middle block of the 25 we checked is 247 m² with 7.6 m of street frontage. The smallest was 91 m² and the largest 684 m². Zones in the sample: R1 (19), E1 (6).
The 25 blocks we checked, by land size.
What homes sell for in postcode 2041
Median sale prices for the whole of postcode 2041, January to March 2026. These cover every suburb sharing the postcode, not Balmain alone, and they are not a value for any one block.
- Houses: $2.79m (36 sales)
- Units and apartments: $1.73m (11 to 30 sales, a small sample)
Source: NSW Government Rent and Sales Report (Department of Communities and Justice), sales tables by postcode, NSW Government. Updated each quarter.
A granny flat
0 of the 25 blocks we checked could take one. Inner West LEP cl 5.4(9) — the greater of 60 m² or 35% of the house’s total floor area, parking excluded. Separately, the state Housing SEPP allows a granny flat of up to 60 m² through the ten-day complying-development route on a lot of 450 m² or more with a 12 m frontage, where the land is not flood, bushfire or heritage constrained.
Dual occupancy (duplex) rules in Balmain
19 of the 25 blocks we checked could carry two or more separate homes today.
Inner West LEP sets no minimum lot size or frontage for a dual occupancy — in R2 the land use table permits anything it does not expressly prohibit, and dual occupancies are not prohibited there, so it is judged on Council's DCP; the Lot Size Map governs any split into two titles
Low and Mid-Rise
None of the 25 blocks we checked fell inside the state Low and Mid-Rise area, so in this part of Balmain the LEP minimums are what count. The boundary is a walking distance from a listed centre, so it can cut through a suburb — the checker reads which side of it your own address sits on.
What else turned up
25 of 25 carried a heritage listing or conservation area. Any of those takes a block out of the fast-track routes and into a full DA, so it changes the answer more than the lot size does.
How we got these numbers
We took 25 real Balmain street addresses from the NSW geocoder and ran every one through the same engine this site runs for you, reading the planning controls live. Nothing here is modelled or estimated.
It is a sample, not a census. The addresses are a spread across what the geocoder returns, so treat these as "of the 25 blocks we checked" rather than a figure for every block in Balmain. Your own block is the only one that answers for itself — that is what the box on the right is for.
Enter the address — lot, frontage, zone, constraints and what it can carry.