NCC 2022 and AS 3600 updates have several implications for the design and use of permanent formwork in areas including combustibility, concrete design and detailing for ductility.
A new edition of the National Construction Code (NCC) is issued every three years and usually contains a range of amendments to industry standards and regulations that engineers need to quickly familiarise themselves with, because compliance becomes mandatory for all future building projects.
The changes introduced last year, however, were some of the most far-reaching in the code’s history and covered everything from fire safety, waterproofing and the number of exits required to a new consistent volume structure, plumbing and energy efficiency.
The sweeping NCC 2022 changes have meant that the CodeMark Certification Scheme, a voluntary third-party compliance scheme run by the Australian Building Codes Board, has had to revise its criteria accordingly.
New CodeMark to NCC 2022
One company that has already updated its CodeMark is AFS, a leading supplier of load-bearing permanent formwork in Australia for external and internal reinforced concrete walls in apartments, offices, warehouses and a range of other buildings.
Its innovative walling systems have been integrated into thousands of projects nationwide and can be installed much more rapidly than conventional alternatives:
- Logicwall is a lightweight fibre cement-steel stud permanent formwork system ideal for stair shafts, balustrades, blade walls, internal party walls, corridors, façades and boundary walls.
- Rediwall is a versatile system made from prefabricated PVC panels and interconnecting components that snap or slide into place. It’s suitable for both above- and below-ground applications such as basements, blade walls, columns, party walls, retention tanks, retaining walls, landscaping walls, foundation walls, and service and stormwater pits.
“The changes to the NCC are certainly substantial and we have obtained new CodeMark certificates for our products to confirm that they are fully compliant,” said Stephen Nash, Senior Building Systems Engineer at AFS, a CSR brand.
“CodeMark Certification is recognised throughout the construction industry and provides greater confidence to the certifier that the product compliance requirements of the NCC lists prove that it’s been fully tested to achieve the required performance.”
The NCC stipulates that building materials used as internal lining needs to comply with fire hazard standards.
NCC 2022 provides clearer provisions regarding the fire performance of a range of materials based on feedback from stakeholders. The additional concessions include thermal breaks, masonry wall components, reinforcing bars encased in concrete and weather sealing materials.
The code stipulates which materials are deemed non-combustible in particular situations. Combustibility is defined by how easily a product catches fire from a fire source, whether the fire is likely to spread from that fire source.
“Rediwall has been fire tested to AS 5113 and passed the flame-spread criteria. The Rediwall product did not promote fire spread beyond the test specimen and self-extinguished once the fire source was removed,” Nash said.
“For Logicwall, the product is a completely deemed-to-satisfy, non-combustible wall solution.”
One consequence of NCC 2022 referencing the further updated AS 3600-2018 Amendment 2 may be a reduction in unnecessary expenses related to ”ductility” of reinforced concrete walls.
The term refers to the degree to which a material can sustain changes in shape under tensile stress.
It’s particularly important when assessing the potential impact of seismic actions. Buildings over eight storeys generally need more ductility to cope with any ground movement.
All proposed new buildings are rated for ductility, but previous definitions have led to confusion and an overcautious approach.
“There are now two categories in AS 3600-2018, ‘limited ductile’ and ‘non-ductile’,” Nash said. “For buildings under eight storeys, non-ductile design is usually completely safe and is adequate to cater of the expected design seismic actions.
“Non-ductile design is also a more economic option, but until now many engineers were using higher degrees of ductility to be compliant because the standard was unclear.”
AFS has design and reinforcement detailing provisions for both non-ductile and limited ductile wall options, as its products are suitable for either. AFS also has provisions for the design and detailing for Rediwall columns and blade walls.
“We can explain and provide technical support to our customers to show exactly the ways NCC 2022 will affect them and provide engineering guidance to the optimal reinforced concrete wall design utilising Rediwall and Logicwall,” Nash said.
“There are so many updates to AS 3600 in a relatively short period of time that it can be confusing to try and understand them all. That’s why we’ve fully revised and updated our AFS design and installation manuals and secured all the relevant CodeMark certifications to confirm our compliance to the NCC.”