Building permit for a granny flat.
What most people call a granny flat is a small second dwelling under the Building Regulations 2018. Many no longer need a planning permit, but every one needs a building permit.
What counts as a small second dwelling
The Building Regulations 2018 define a small second dwelling as a self-contained Class 1a building with a gross floor area of 60 m² or less, on the same lot as an existing single house.
The planning rules add that it must have a kitchen, bathroom and toilet, it cannot be subdivided or sold separately from the main house, and it cannot be connected to reticulated natural gas.
Planning permit
A small second dwelling does not need a planning permit in most residential areas. One is still needed where the zone or an overlay requires it, for example flooding or environmental controls. Your planning property report shows which controls apply to your land.
Building rules that apply
- It must be set back behind the front wall of the existing house that faces the front street, and porches, verandahs, eaves, decks over 800 mm high and similar items cannot extend into that setback (regulation 74A). A design that does not meet this needs the council's report and consent.
- The other Part 5 siting rules apply, including rules written for small second dwellings on private open space and accessibility (regulations 86A and 86B).
- It needs a house energy rating, like any new home.
- It is inspected at each mandatory stage, and needs an occupancy permit before anyone lives in it.
Request a quote
Request a quote online, or email what you have to info@cortekgroup.com.au, and we will quote a fixed fee for your building permit. For the permit itself we will need:
- The certificate of title and plan of subdivision, with any covenants or section 173 agreements
- The council's property information under regulation 51(2), and its legal point of stormwater discharge
- Drawings and specifications issued for construction
- A soil report, and the engineer's drawings, computations and design certificate
- A house energy rating report with the energy endorsed drawings
- The planning permit and endorsed plans, if the project needs one
- A bushfire assessment, if the site is in a bushfire prone area
- A septic permit from the council, if the site is not sewered
- If a builder is doing the work, the contract extract and, where it applies, the domestic building insurance certificate
- If you are an owner-builder, your certificate of consent from the BPC, where one is required
The full list is in our building permit documentation checklist.