NCC 2019 Volume Three
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Part A1 Interpreting the NCC
This Part explains important concepts on how the NCC must be interpreted and applied. There are certain conventions and approaches that need to be taken into account when using the NCC. This includes interpreting specific language and terms. This is critical in understanding the intended technical and legal meaning of the NCC. This Part also explains the difference between the mandatory parts of the NCC and parts that are only explanatory or guidance in nature.
The following components of the NCC are non-mandatory and informative:
Content identified as “explanatory information”.
For Volumes One and Two, the “Introduction to this Part or Section” information, located at the beginning of each Part or Section.
For Volume Three, the “Introduction to this Section” information, located at the beginning of each Section.
Words in italics must be interpreted in accordance with—
definitions provided in Schedule 3, unless the contrary intention appears; and
additional definitions in State or Territory appendices, as appropriate.
For Volume Three, if a word is not defined in Schedule 3, the meaning (if any) attributed to it under AS/NZS 3500.0 Glossary of Terms should be used unless the contrary intention appears.
The NCC must be interpreted and applied in accordance with the following:
A reference to a building is a reference to an entire building or part of a building (as the case requires).
A reference to a plumbing or drainage solution, or product in Volume Three is a reference to an entire installation, system or product, or part of an installation, system or product (as the case requires).
A reference in a Performance Requirement to “the degree necessary” means—
that consideration of all the criteria referred to in the Performance Requirement will determine the outcome appropriate to the circumstances; and
that in certain cases it may not be necessary to incorporate any specific measures to meet the relevant Performance Requirement.
For Volume Three the “Introduction to this Part” information, located at the beginning of each Part, is mandatory and is provided to specify where each Part applies.
An “Application” statement is mandatory and is provided to specify where and when a requirement or provision applies.
A “Limitation” statement is mandatory and is provided to specify where and when the application of a requirement or provision is limited to a certain circumstance.
An “Exemption” statement is mandatory and is provided to specify where or when a requirement or provision does not need to be complied with.
A “Note” is part of a provision or requirement and provides additional mandatory instructions.
Figures in the NCC are used to illustrate specific issues referenced in the associated text. They are not to be construed as containing all design information that is required for that particular building element or situation.
The defined symbols and abbreviations listed in Schedule 2.
A reference to a building class is understood to be a reference to all the sub-classifications of that class.
The following sub-classifications apply:
Classes 1a and 1b are sub-classifications of Class 1.
Classes 7a and 7b are sub-classifications of Class 7.
Classes 9a, 9b and 9c are sub-classifications of Class 9.
Classes 10a, 10b and 10c are sub-classifications of Class 10.
A reference to a sub-classification is solely to that sub-classification.
Explanatory information and Introduction to this Section information contained in the NCC or Introduction to this Part information contained in Volumes One and Two of the NCC are non-mandatory and are provided for guidance purposes only. This informative material should be read in conjunction with the technical provisions of the NCC. Any statements made in the informative and guidance components of the NCC should not be taken to override the NCC. Unlike the NCC, which is adopted by legislation, the informative and guidance components are not called up into legislation and they do not cover State and Territory variations and additions. Because informative and guidance components of the NCC do not have regulatory force, the ABCB accepts no responsibility for its contents when applied to specific buildings or any liability which may result from its use.
Defined words provide the precise meaning and expressions of key words used for understanding and complying with the NCC. Where a word is not defined in the NCC, the relevant common meaning of the word should be used.
Generally, a reference to a building is a reference to the whole building, regardless of classification. However, when a provision is applicable to a specific class or classes of building, that reference to a building may be a reference to the whole building or part of the building depending on how the building is classified.
Whether a provision applies or not depends on the circumstances of the case and the circumstances in which the reference is made. For example, where a building has a single classification, a reference to a building in the NCC is understandably a reference to a whole building. However, where a building has parts of different classification, unless the contrary intention appears (i.e. there is a specific reference to the whole building), a reference to a building in the NCC is a reference to the relevant part of the building. This means that each part of the building must comply with the relevant provisions for its classification.
A number of the Performance Requirements of the NCC use the expression “to the degree necessary” or “appropriate to”. These expressions provide flexibility by allowing appropriate authorities to determine the degree of compliance necessary in a particular case. Therefore any part of the NCC that uses these expressions should be referenced against the requirements of the appropriate authority. For example, an appropriate authority might judge that an item need not be installed, or a particular level of performance be achieved.
Application, Limitation, and Exemption statements are used to identify provisions that may or may not apply in certain situations, to varying degrees.
Classes 1a and 1b, 7a and 7b, 9a, 9b and 9c, and 10a, 10b and 10c are separate classifications. In the NCC, when the designation 'a', 'b' or 'c' is not applied, the reference is to all buildings of the general class. For example, 'Class 9b' refers only to Class 9b buildings, but 'Class 9' refers to Classes 9a, 9b and 9c.
Figures are used to explain the requirements of a particular clause. To ensure the context of the requirement is clearly understood, adjacent construction elements of the building that would normally be required in that particular situation are not always shown. Accordingly, aspects of figures that are not shown should not be interpreted as meaning these construction details are not required. Therefore a figure must not be used as an indication of the full construction requirements in a given situation, as the only available option, or a substitute for referencing appropriate construction requirements (in other sources) for a given clause.