Secondary dwelling? Auxiliary Unit? Dual Occupancy? They all look the same but what are the key differences?
Generally, a ‘secondary dwelling’ or more commonly known as a ‘grannyflat’ is a self-contained unit ancillary to a Dwelling house usually for a member of the household group (e.g. direct blood relatives of the primary dwelling house). A Secondary Dwelling cannot be rented separately to the primary dwelling and should genuinely be used as a ‘grannyflat’.
An Auxiliary Unit is restricted by similar provisions to a Secondary Dwelling but rented separately to the primary Dwelling house. The majority of Local Government Areas in South-East Queensland allow Auxiliary Units without any infrastructure charges but it is always good to check with your Local Council or a town planner. An Auxiliary Unit cannot be strata-titled or sold separately to the primary dwelling.
A Dual Occupancy is a completely separate household to the Dwelling House that is already on the site. It can be rented separately from the primary dwelling house on the same title and also strata-titled and sold off separately to the primary house. Think of a Dual Occupancy as a Multiple Dwelling development but only 2 units instead of 3+. Infrastructure charges are applicable, Council approval is required…etc.
Some general differences between the above uses:
| Secondary Dwelling | Auxiliary Unit | Dual Occupancy | |
| Crossovers | One vehicular crossover | One vehicular crossover | Two crossovers may be allowable |
| Cars | One additional car park may be required | Two additional car parks may be required | Two additional car parking bays will be required |
| Functions | No limitation | One/Two bedrooms, No more than one kitchen, One living space | No limitation |
| Rentable or sellable? | Must be occupied by the same household group as the primary dwelling | Can be occupied by a separate household group and independently rented out | Can be occupied by a separate household group and independently rented out or sold |
| Services | No separate services are required. | Can have separate meters installed if desired. | Separate services and meters are required. |
| Letter Box | No separate letterbox is allowed | A separate letterbox may be allowed. | A separate letterbox is required |
| Fire separation | Fire separation is optional | Fire separation is mandatory | Fire separation is mandatory |
| Council rates | No extra rates apply for a secondary dwelling | Additional rates apply | Additional rates apply |
| Infrastructure charges? | No infrastructure charges are applicable | Some Council regions require infrastructure charges to be paid. | Infrastructure charges are payable. |
| Rubbish bins | No additional bins are required. | No additional bins are required. | Separate bin storage and services are required. |
Feature image: http://projecthabitation.com.au/
This article has been written by Alexander Steffan from Steffan Town Planning.
