Granny Flats Unlock New Homes

Australia’s existing suburbs may have room for millions of additional homes without requiring new housing estates.

Analysis by property platform Archistar found that 44% of suburban properties could accommodate another dwelling or duplex under current planning rules. In total, Australia’s suburbs may have capacity for another 3.6 million homes.

Granny flats offer one of the quickest and most affordable ways to use that capacity. Around 2.5 million residential lots could hold at least one granny flat, including 800,000 sites within two kilometres of a train station and 755,000 near hospitals.

The approach could help several housing challenges at once. Families can create accommodation for ageing parents, adult children or siblings, while downsizers can remain in familiar communities. Adding a smaller dwelling may also free up larger homes for growing families.

For investors, granny flats can provide strong rental returns because their construction cost is relatively low compared with the rent they generate. However, feasibility depends on planning rules, access, services, building costs and the configuration of the existing block.

The research also highlights Australia’s “missing middle”: established suburbs dominated by detached homes but lacking duplexes, townhouses and other medium-density options.

Land capacity alone will not solve the shortage. Faster approvals, consistent planning rules and viable construction costs are still required. Nevertheless, better use of existing blocks could add housing in locations where infrastructure, employment and community services are established.

Rather than relying solely on outer-suburban expansion, Australia may have a part of its housing solution potentially sitting in its backyards.