The National Construction Code (NCC) is a performance-based code which sets out the requirements for the construction of buildings, including plumbing and drainage.
The NCC has two different mandatory requirements:
- Performance Requirements outline certain criteria which must be met, and
- General Requirements which cover other aspects of applying the NCC. This includes its interpretation, reference documents, the acceptance of design and construction (including related evidence of suitability/documentation) and the classification of buildings within the NCC.
The NCC has both guidance information and compliance requirement. The Performance Requirements of the NCC being the minimum level that buildings, building elements and plumbing and drainage systems must meet. A building, plumbing or drainage solution will comply with the NCC if it satisfies the Performance Requirements.
Compliance Pathways
The key to the performance-based NCC is that there is no obligation to adopt any particular material, component, design factor or construction method.
This provides for a choice of compliance pathways. The Performance Requirements can be met using either a Deemed-to-Satisfy (DTS) Solution, or a Performance Solution (Alternative Solution).
Deemed-to-Satisfy Solution
A DTS Solution follows a set recipe of what, when and how to do something. It uses the DTS Solutions from the NCC, which include materials, components, design factors and construction methods that, if used, are deemed to meet the Performance Requirements.
Performance Solution
A Performance Solution is unique for each individual situation. These solutions are often flexible in achieving the outcomes and encouraging innovative design and technology use. A Performance Solution directly addresses the Performance Requirements by using one or more of the Assessment Methods available in the NCC.
Essentially, if you are building or designing a standard home, it will likely utilise a DTS Solution. If you’re building or designing something a little outside the box, a Performance Solutions might be used. Generally, a DTS Solution is the most common pathway to compliance with the NCC.
Documents available for consideration as part of a Performance Solution
The majority of NCC referenced documents, such as Australian Standards, form part of the Deemed-to-Satisfy Provisions of the NCC. Therefore, use of a version of a document other than the one referenced in the NCC requires the use of a Performance Solution.
The ABCB has established an initiative to promote revised or amended documents that are not referenced in the NCC, but have been accepted as being suitable for referencing in a future edition of the NCC, and therefore may be suitable for consideration as part of a Performance Solution. Remember, practitioners have choices about which NCC compliance path they wish to follow, but are responsible for demonstrating compliance through adequate documentation of the Assessment Methods used.
How do I know if compliance is achieved?
If a DTS solution is used, compliance is achieved through meeting the requirements of the DtS solution. These are outlined in the NCC and may utilise a other documents referenced by the NCC.
If a Performance Solution is used, compliance is achieved using the NCC’s Assessment Methods. Any combination of the four Assessment Methods can be used to determine that a building or plumbing and drainage solution complies with the Performance Requirements:
- Evidence of Suitability requires evidence, to support claims that a material, form of construction or design meets the Performance Requirements or DTS Provisions.
- Verification Methods are tests, inspections, calculations or other methods, which determine whether a proposed building or plumbing and drainage solution complies with the relevant Performance Requirements. Verification Methods are not limited to using those in the NCC. Another Verification Method may be used if the appropriate regulatory authority is satisfied that it establishes compliance with the NCC.
- Comparison with the DTS Provisions allows a comparison between the DTS Provision and a proposed building or plumbing and drainage solution. If it can be demonstrated to the appropriate authority that the solution complies in an equivalent or superior way to the DTS Provisions, then it can be deemed to meet the relevant Performance Requirements.
- Expert Judgement is the judgement of a person who has the qualifications and experience necessary to determine whether a building or plumbing and drainage solution complies with the Performance Requirements. Where physical criteria are unable to be tested or modelled by calculation, the opinion of a technical expert may be accepted.