Building Class

Building Classifications and Classes

When you talk to professionals in the industry, they will refer to your building by its classification or class. A classification groups together buildings of a similar use so that the rules that apply to a class, apply to all the buildings in that class. So, it really pays to know the category your proposed building will be under. We have put together a quick list that will help you to easily identify your building project.


Residential Construction normally deals with Class 1 and 10 and Commercial Construction is Class 2 to 9.

These buildings are classified as follows:

Extract from the Building Code of Australia (BCA) – Part A

Class 1: one or more buildings which in association constitute—

(a)          Class 1a — a single dwelling being—

(i)            a detached house; or

(ii)           one of a group of two or more attached dwellings, each being a building, separated by a fire-resisting wall, including a row house, terrace house, town house or villa unit; or

(b)          Class 1b —

(i)            a boarding house, guest house, hostel or the like—

(A)          with a total area of all floors not exceeding 300 m2 measured over the enclosing walls of the Class 1b; and

(B)          in which not more than 12 persons would ordinarily be resident; or

(ii)           4 or more single dwellings located on one allotment and used for short-term holiday accommodation, which are not located above or below another dwelling or another Class of building other than a private garage.


Class 2: a building containing 2 or more sole-occupancy units each being a separate dwelling.


Class 3: a residential building, other than a building of Class 1 or 2, which is a common place of long term or transient living for a number of unrelated persons, including—

(a)          a boarding house, guest house, hostel, lodging house or backpackers accommodation; or

(b)          a residential part of a hotel or motel; or

(c)           a residential part of a school; or

(d)          accommodation for the aged, children or people with disabilities; or

(e)          a residential part of a health-care building which accommodates members of staff; or

(f)           a residential part of a detention centre.


Class 4: a dwelling in a building that is Class 5, 6, 7, 8 or 9 if it is the only dwelling in the building.


Class 5: an office building used for professional or commercial purposes, excluding buildings of Class 6, 7, 8 or 9.


Class 6: a shop or other building for the sale of goods by retail or the supply of services direct to the public, including—

(a)          an eating room, café, restaurant, milk or soft-drink bar; or

(b)          a dining room, bar area that is not an assembly building, shop or kiosk part of a hotel or motel; or

(c)           a hairdresser’s or barber’s shop, public laundry, or undertaker’s establishment; or

(d)          market or sale room, showroom, or service station.


Class 7: a building which is—

(a)          Class 7a — a carpark; or

(b)          Class 7b — for storage, or display of goods or produce for sale by wholesale.


Class 8: a laboratory, or a building in which a handicraft or process for the production, assembling, altering, repairing, packing, finishing, or cleaning of goods or produce is carried on for trade, sale, or gain.


Class 9: a building of a public nature—

(a)          Class 9a — a health-care building, including those parts of the building set aside as a laboratory; or

(b)          Class 9b — an assembly building, including a trade workshop, laboratory or the like in a primary or secondary school, but excluding any other parts of the building that are of another Class; or

(c)           Class 9c — an aged care building.


Class 10: a non-habitable building or structure—

(a)          Class 10a — a non-habitable building being a private garage, carport, shed, or the like; or

(b)          Class 10b — a structure being a fence, mast, antenna, retaining or free-standing wall, swimming pool, or the like; or

(c)           Class 10c — a private bushfire shelter.

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I am a Director of Devcert and have been a Building Surveyor since 1989. I have a bachelor degree in building surveying and I am a qualified carpenter. I have been in the construction industry since 1981. I have a real passion for the building certification profession as I believe building certifiers are the general practitioners of the construction industry. Our role is not only to know building law and apply it, our role includes assisting in the development of the knowledge of all in the industry by sharing our knowledge and experience.