The Australian Building Codes Board (ABCB) produces and maintains the National Construction Code (NCC) on behalf of the Commonwealth and State and Territory Governments. It provides the minimum mandatory requirements for safety, health, amenity, and sustainability for building works of both new and existing buildings throughout Australia.1 Building work is defined broadly in the NCC and includes the following activities:
- construction
- alteration
- extension
- restoration
- repair
- demolition
- dismantling
- installation of fittings such as heating, lighting, sanitation, ventilation, power supply, drainage, etc.
- any operation to prepare for or finish the activities mentioned above, including site clearance, laying of foundations, provision of access works, etc.
If you are unsure about how your building should be classified, it is best to consult with an Appropriate Authority.
What is an Appropriate Authority?
As defined by the NCC, an Appropriate Authority is an individual or entity with the statutory responsibility to approve building and plumbing works and enforce relevant regulations. State and Territory building and plumbing regulations determine who is considered an Appropriate Authority. Generally, a person with an interest in building work cannot be appointed.
An interest includes:
- legal or equitable interest in the land where the building work will be carried out;
- financial interest in the construction or completion of the work; or
- intention to carry out any of the building work, including the planning and design.
An Appropriate Authority is typically a building certifier, building surveyor, or plumbing inspector.
NCC and building classifications
The NCC incorporates all building work requirements into a single code containing three volumes. The Building Code of Australia (BCA) is Volumes One and Two, and the Plumbing Code of Australia (PCA) is Volume Three. Copies of these codes and amendments can be accessed at the NCC website upon free registration.
This 5-minute video explains NCC and how it classifies buildings:
The NCC is given legal effect through the respective state/territory legislation. Any NCC provision may be overridden by or subject to the legislation of the state or territory. As such, they must always be read in conjunction with each other.
Construction plans, working drawings and specifications
Construction plans and working drawings are documents containing relevant information about a building's construction. They are used to convey technical details.
Construction plan
A construction plan, also known as the project plan, represents the site of a project and all project-related activities. The plan covers the location of the project site, the structures and other facilities, the grading operations, the implementation schedules, and other specific details relating to the site of the project.
Working drawings
Working drawings refer to accurate visual descriptions of what will be built, where the building will be situated, the size of the rooms and the relationship of the elements within.
Construction plans and specifications must follow the Australian Standard 1100 (AS 1100), which provides the standards for technical drawings, diagrams, charts, and tables.
At the minimum, construction plans, working drawings, and specifications should include the following information:
- a drawing title that indicates what the drawing relates to
- a drawing number and version
- the date the plan was completed
- the block, section, and division of the land
- the project street address
- the names of the landowners
- the name of the entity who prepared the plans, including the individual responsible for other relevant design work.
They must also:
- clearly differentiate between the proposed building and other existing structures using colours, shadings, or codes with associated legends;
- include dimensions of elements such as timber, windows, or structural beams;
- present information clearly and legibly;
- use appropriate drawing scales; and
- use drawing sheets appropriate to the type of drawing and its details.
There are different types of working drawings that show the different aspects and perspectives of building work. These types are summarised in the table below. Simple examples of each of these can be found on this Designing Building website.
| Description | Types of working drawings |
|---|---|
| Location Plan |
|
| Site Plan |
|
| Elevation |
|
| Detail Drawing |
|
| Section |
|
| Floor Plan |
|
| Reflected Ceiling Plan |
|
| Demolition Plan |
|
Specifications
Specifications (or informally, specs) are usually developed during the design phase and provide detailed descriptions and conditions for the materials, work, and product required for the project. They do not include quantities or illustrations and must be reviewed together with other construction documents. They may include the process for determining if the requirements of the specifications are met. They must also be specific to the project.
Specifications perform different roles, including:
- a document showing compliance with relevant building codes and standards
- a written record of design decisions as well as required materials and standards to be met
- a tendering document
- a legal document
- an onsite working document
- a project management tool.
The following are some examples of specifications that you may use in a proposed project:
- earthworks
- erosion and sediment controls
- concrete works
- fencing
- building works
- roads
- electrical systems
- water reticulation systems.
Construction specifications can be classified into three different types: Performance Specifications, Prescriptive Specifications, and Direct/Proprietary Specifications.
Performance specifications
- Specifies how the final component should perform after installation
- Allows more freedom to innovate and adopt cost-effective methods
Prescriptive specifications
- Shows the details of the materials to be used
- Indicates the required workmanship and installation
- Provides more certainty regarding the final product compared to performance specifications
Direct/Proprietary specifications
- Used if a project requires a specific product.
Behaviour of structures under stress
Building structures should be designed using materials to withstand different forces such as compression, tension, bending, torsion, shear and combinations of these forces.
This short video explains how physical loads can affect buildings and structures:
Australian Standards and other documentation will contain provisions and requirements on ensuring that buildings remain water-resistant and can withstand elements such as stress and exposure.
Section A6.11 of NCC Volume 2 states that a building or part of a building may have multiple purposes and, therefore, multiple classifications. Therefore, all the relevant requirements that apply to each of the classifications for that building must be met by a building (or part of a building). If a building has more than one classification, the more stringent class requirements will apply. Stringency is based on several factors, including but not limited to the closest resemblance of the building to a specific building class, fire load, and risks to the safety, health, and amenity of the people using the building, and are ideally decided by the relevant authority with statutory responsibility to determine building classification. More often than not, requirements for Class 1 and Class 10 buildings override other requirements since Class 1, and Class 10 building requirements apply to buildings with permanent occupants or users.
Generally, if 10 per cent or less of the floor area of a storey is used for a purpose that could be classified differently from the remainder of said storey, that 10 per cent or less part may be classified as being the same as the remainder. For example, if a single storey factory (Class 8) has an office (Class 5) taking up 6 per cent of the whole factory's floor area, then the entire factory (including the office) can be classified as a Class 8 building. However, if the office's floor area covers 11 per cent of the floor area of the factory, the office must then be classified as Class 5 and the rest of the factory Class 8. This approach (i.e. using 10 per cent as a threshold to determine building classification) is likely to be taken by a contractor who is unaware about what the exact usage of a building would be after its sale or to optimise the versatility of the use of the house.
Australian Standards
Australian Standards (AS) are compiled by Standards Australia International Limited (formerly Standards Australia, SA and before that the Standards Association of Australia, SAA). These documents have been specifically created to outline the specifications that relate to building and construction procedures and products to make sure that they comply with safety and performance standards. Construction procedures are a series of steps followed in a regular definite order to accomplish a construction goal. An example of this is the procedure for cladding a window.
Australian Standards cover a wide range of process and quality requirements, including:
- Testing methods
- Installation methods
- Finishing standards and requirements
- Ratings and classifications
- Compliance with regulatory bodies.
With an AS reference, you must consider whether the AS is referenced in full or in part and if there are any new editions and amendments.
Some AS are referenced in their entirety, while some are referenced only in part. If the AS is only referenced in part, then the other parts that are not referenced are considered irrelevant and have no authority. In addition, new amendments and editions of the AS are not automatically adopted by the NCC. This means that you only need to comply with the edition of the AS that was referenced.
Performance hierarchy
The NCC is a performance-based code. Its fundamental principle is to develop innovative solutions by regulating building outcomes instead of providing quantitative measures of compliance.
This short video explains how the essence of NCC and how a building can comply with Performance Requirements using a compliance option:
This fundamental principle is guided by what you call a 'performance hierarchy' or a hierarchy of guidance and code compliance levels, as seen in the figure below:
The Governing Requirements (also known as General Requirements of the NCC) are outlined in Section A of Volume One, Section 1 of Volume Two and Section A of Volume Three. These provide the rules and instructions for using and complying with the NCC, including the following:
- interpretation of the NCC
- referenced documents such as Australian Standards
- acceptance of design and construction (such as evidence of suitability and other related documentation)
- classification of buildings
Building classifications determine the Performance Requirements that you must follow in any given project. Some of the Performance Requirements are only applicable to certain building classifications. Always check with the NCC or an Appropriate Authority if you are unsure which requirements you have to apply to your building.
The Performance Requirements sit at the top of the compliance hierarchy. These are requirements that state the minimum level of performance for buildings, plumbing, and drainage installations. Performance Requirements are qualitative statements that describe the needs of building occupants.
Codes of states and territories
Some states and territories also have their own codes relating to residential building and construction projects. Examples of these are the Queensland Development Code, South Australia's residential development code, and Western Australia's residential design codes.
Some of these codes are specific and only apply to the states and territories where they are written.
For example, in SA's code, residential development can apply to the following:
- single-storey upgrades to existing homes
- detached and semi-detached single-storey and two-storey houses
- verandas, rainwater tanks, carports, and sheds.
State and territory legislation
Depending on the state/territory that you are in and the classification of your building, there are different acts and regulations that you must follow for your project.
Before proceeding, you must first understand the difference between acts and regulations.
Acts
An act is legislation passed by the Parliament and amended only by another act. It sets out broad legal and policy principles.
Regulations
A regulation (together with rules, codes, etc.) is an example of a 'subsidiary legislation.' It contains guidelines that tell you how to apply the provisions of an act.
You can see some of the acts and regulations in each state and territory relevant to different building classifications on the map.
Environmental requirements
Construction methods that neglect to control pollution can cause lasting and permanent damage to land, groundwater, and their surrounding environment. The environmental risk is greater in construction projects near creeks, waterways, and coastal areas. Construction in metropolitan and built-up areas can lead to air and noise pollution in surrounding communities and neighbourhoods.
Project managers and builders need to adhere to all local, state, and federal environmental regulations. It is important to note that the table below does not show all environmental regulations in each state and territory. It is the responsibility of each project manager and builder to consult with each governing authority to ensure that all the relevant environmental regulations are followed.
Each state and territory is governed and regulated by an environmental regulatory authority with enforcement powers to impose sanctions, issue fines, and cancel licences. The map below outlines the environmental authority of each state and territory in Australia.
Work health and safety legislation
The work health and safety (WHS) legislation for each state and territory and the corresponding regulators are shown on the following map:
Construction code of practice
Each state and territory also have its own Construction Code of Practice. A Code of Practice provides practical guidance to principal contractors and other persons conducting building work on meeting the WHS legislation and requirements. The following map shows the relevant codes per state and territory with the links to their websites.
*As of the time of writing, Queensland, South Australia, Victoria, and Western Australia do not have a dedicated Code of Practice for Construction Work. In which case, you must refer instead to the code of practice relevant to building work, e.g. the state or territory's code of practice for demolition, excavation, etc.
Licences and permits
Before you can undertake your building work, you have to secure several licences and permits first. These may include the following:
- building licences
- plumbing licences
- gas fitting licences
- electrical licences
- development applications
- zoning approvals
- fire management and safety
- connection or work on sewerage/drains
- water usage or constructing a bore or well
- heavy vehicle licences
- protecting trees and wildlife
- permits to conduct high-risk work
- permits to work on heritage properties
- permits to handle, store and use of chemicals or dangerous substances
- permits to use blasting explosives.
Processes, procedures and techniques of construction
Construction involves several processes, procedures, and techniques. Listed below are some processes involved in construction and the procedures and techniques involved.
Zero-energy building
Zero-energy building is the construction of buildings that produce as much energy as they consume. It is called a 'zero-energy' building because, ideally, the difference between the energy produced by the building and the energy consumed by the building is zero. There are many ways to ensure that a building is built as a zero-energy building, integrating renewable energy sources that power the building. One of the more popular renewable energy sources, especially in hotter climates, is solar energy, which can be harnessed by installing solar panels on the roofs of buildings. Installing heat pumps, high efficiency windows and insulation may also be used to power the building using renewable energy sources.
Demolition
Demolition involves the destruction of building components that are considered obstacles in the building and construction project. Demolition comes in many forms, one of which is non-explosive demolition. Non-explosive demolition involves using techniques that do not require any explosives, such as using a wrecking ball or excavator to take down larger parts of a building or dismantling a building part by part.
Other techniques and terms used in construction
Many processes in construction involve the same techniques, and it will do you good to know some of these techniques. Listed below are examples of some of these techniques. You will find more techniques in the glossary of this module.
- Admixture (n.) – materials added to mortar or concrete to achieve particular modifications to the typical properties of the basic material
- Brace (n.) – a member, usually a diagonal, which resists lateral loads and movements of a structure
- Curing (v.) – treatment of concrete or cement rendering to facilitate hardening
- Gable (n.) – the triangular end of a house formed at the end of a pitched roof, from eaves level to apex
- Masonry (n.) – brick, concrete, stone, artificial stone or terra cotta laid in mortar
- Mortar (n.) – a composition of lime, cement and sand mixed with water in various proportions
- Nogging (n.) – a horizontal piece of timber fixed between studs in a framed wall
- Pilot hole (n.) – a hole drilled to receive a nail or a screw
- Plant (n.) – Tools and equipment used in building operations
- Plumb (adj.) – vertical or perpendicular
- Sanding (v.) – the smoothing down of visible timber or other surfaces with sandpaper
- Scaffolding (n.) – a temporary structure specifically erected to support access platforms or working platforms
- Strip flooring (n.) – flooring laid as separate boards, fitting together with a tongue on one edge and a mating groove on the other
