Sometimes people need another room in their homes, often a bedroom. Instead of building an extension, many choose to convert their existing garage into a bedroom, living room, study or any other room considered a habitable room.
A habitable room as defined in Volume 2 of the National Construction Code (NCC - used to be called the Building Code of Australia BCA) is defined as:

"Habitable room means a room used for normal domestic activities, and— (a) includes a bedroom, living room, lounge room, music room, television room, kitchen, dining room, sewing room, study, playroom, family room, home theatre and sunroom;
(b) excludes a bathroom, laundry, water closet, pantry, walk-in wardrobe, corridor, hallway, lobby, photographic darkroom, clothes-drying room, and other spaces of a specialised nature occupied neither frequently nor for extended periods."


Why does it matter how a room is defined?

All buildings in Australia are defined by a Class. There are 10 classes in total, with some sub classes, and the reason the classes exist is to ensure the building is designed to meet the standard in the National Construction Code to comply with adequate:
Damp and Weatherproofing
Fire safety
Health and amenity
Safe movement and access
Energy Efficiency

A garage is a Class 10 building, specifically a Class 10a bulding, and an average free standing house is a Class 1 building. So coverting a garage to a habitable room as a part of a free standing house means you are changing the Class from a Class 10a to a Class 1. You might already realise that the requirements for a garage are not as strict as a house requirements in terms of the list above, so to make it a bedroom you legally need to address certain aspects to make the garage comply with the National Construction Code. There are quite a few considerations to take into account when deciding on utilising your garage as a habitable room. As every situation will be different, I will outline some things to consider, however, you should seek professional advice from a registered building pracitioner such as an architect, building designer or building surveyor.

Some of the most common things to consider are:

►Windows - Habitable Rooms must have access to suffiecient natural lighting
►Lighting - Electricty for at least one light fixture of at least 5 W/m2 of floor area
►Energy rating - Adequate walls and ceiling insulation will be required to meet minimum thermal performance compliance
►Ceiling Height - Ceiling must be a minimum of 2.4 metres high (non habitable rooms must only be 2.1 metres high)
►Siting - Location of garage of your property - this has quite a few factors to consider
►Fire Safety - Depending on the garage structure, it might not currently meet required fire ratings, especially if its a very old garage made of fibro or sheet metal and on the boundary.
►Fire Safety - Smoke Detectors, not a big issue usually, one will be required though. However, if you live in a medium to high risk bush fire designated area it could be potentially very expensive to get the garage up to standard if the house was built prior to 2009
►Waterproofing - Garage must be waterproof/damp proof to make it adequate for human healthy habitation - this can be a big issues in garage floor with no moisture vapour barrier below slab
►Pool Safety - If the existing garage opens to a pool area, a barrier or other methods will need to be adopted as so no person can enter the pool area without the use of safety systems as per NCC

These are just some of the main points to consider.

Each State & Territory may have variations to requirements to meet compliance. Another aspect to consider with a garage is to what sort of chemicals may have been spilt on the floor over years. Commonly oil and petrol soak into slabs over years, and habiting a space that has had a lot of exposure to these subtances could potentially cause a health risk to the occupier of the space over time.


The above information outlines requirements to do with building codes, however, your local municipality may also require you to apply for a planning permit as well depending on the extent of external works you may decide to undertake.

If you add windows to the garage, or change the roller door to a solid wall or a window, this may have an impact on streetscape amenity, or overlooking on your neighbours meaning you may need council approval with a planing permit on top of a building permit.

You can goto your local councils website and search for information about whether your proposed alteration needs a planning permit, or if you are not certain, call the planning department or go in and ask to speak to a planner.

Next Page I will go through some example scenarios:


In addition to the information I provide for designing and drafting your own house, I have another side project that tells you how long a house or land has been For Sale or Rent in Australia.
It is also Free to Use and also has a search to give you a price range indication of house and land for sale that doesn't have a listed price.
It is called Get House Date Mobile Friendly too.