Are you wanting to keep up with the latest NCC changes? Navigating how updates to the NCC affect cladding compliance can seem perplexing, but it is crucial to understand the most important parts for builders, designers and architects, to ensure they can be factored into new designs. This article summarises these relevant changes and what they mean to the architectural and construction industry.
The upgraded NCC requirements have provided options to make construction easier, creating a more accessible document and relaxing restrictions on which products are deemed to satisfy. This means a wider range of cladding products can be considered compliant with the NCC 2022 – but it also means specifiers, architects and designers should use discernment when choosing a product, checking it also adheres to other crucial Australian Standards for weatherproofing and non-combustibility. In addition, new changes include a new section on thermal efficiency to increase the holistic sustainability of the building.
The National Construction Code sets out requirements for cladding and façade designs that factor in safety, ease of maintenance, energy efficiency, occupant comfort and durability, ensuring new construction projects are safer, more durable and longer-lasting. The requirements set out by the NCC affect the design, development, and installation of façades, and this impacts which cladding systems and products are chosen, as well as the methods used to install them, factoring in
ventilation as well as a system that can withstand impact. By adhering with these requirements, specifiers ensure the façade contributes to the safety and quality of the building overall.
NCC Requirements for Cladding and Façade Design
General impressions from these changes are that the ABCB has taken a ‘how can we make construction easier?’ type approach, by significantly adding more Deemed-to-Satisfy clauses approving products and installation methods. Some of these are better and readily workable, while others may increase risks around common defects like weatherproofing.
Bonded Laminates
The bonded laminates clause has again been retained in the NCC and is not slated for future amendments. For Fairview, this reinforces full compliance of our relevant products including the popular Vitracore G2 panels.
There’s a key new provision that prevents fixing of certain bonded laminated cladding panels by adhesive only, but this is unlikely to have much impact as the installation recommendations of several main product suppliers already align with this new clause.
Weatherproofing Requirements
The addition of deemed-to-satisfy weatherproofing requirements is a first in NCC 2022, but as waterproofing is one of the most common defects in high-rise construction, some concerns are flagged by the new requirements – and it’s worthy of explanation below:
The advocated change of clause F3D3 implies that – where sarking is used in accordance with AS4200 – that ticks the box for weatherproofing. However we have concerns that under tall building/high wind loads [where sarking can readily tear] this could be problematic.
Moreover, regarding the approval of external metal wall cladding in line with AS1562.1 is – in our opinion – unlikely to enhance waterproofing performance. Waterproofing is the number one defect affecting high-rise constructions, so to assign weatherproofing of wall cladding to a standard designed for roofing performance under wind-loads – with no significant water or weatherproofing requirements – is perplexing. For absolute surety, compliance should be built around system-based weatherproofing testing, not on wind-load strengths or attributes. While not obvious in the code, the requirements of the standard means it is only really applicable for large format roof sheeting products, and not for the majority of metal cladding products used in high-rise façades.
Checking whether a cladding product or system complies with other Australian Standards can assist specifiers in determining which products will truly withstand harsh weather conditions and water damage. AS 4284 is a test for façade systems, assessing performance, energy efficiency and minimal maintenance, which can demonstrate that a product is compliant with NCC weatherproofing requirements while also ensuring a complete, system-based approach is taken to compliance.
Fairview’s range of cladding systems are tested and certified to AS 4284, illustrating their ability to withstand a variety of weather pressures and last longer on façades.
Fire Resistance Requirements
Approving more materials deemed as non-combustible (in terms of their fire resistance) simplifies the choice of construction products and materials and slightly reduces build and product certification costs. This applies to re-cladding and replacement of combustible cladding.
Fire resistance is of paramount importance to ensure occupant safety, so it is important to choose products from the range deemed suitable by the most recent NCC. In the past, use of noncompliant materials has led to the need for cladding removal and replacement on numerous high-rise residential and commercial buildings across Australia. Cladding materials such as Aluminium Composite Panels (ACP) with a combustible polyethylene core and expanded polystyrene (EPS) panels no longer comply with NCC requirements. However, products such as solid aluminium panels or bonded laminates/ACP with a non-combustible mineral or aluminium honeycomb core, are ideal for designers seeking a product that will comply. This being said, it is important to check the specific product to ensure it has been tested to and complies with Australian Standards surrounding combustibility, to truly ascertain whether it will be suitable for your construction project.
Fire testing carried out under AS 1530.1 and AS 1530.3 determine whether a product will not ignite or spread fire. Codemark certifications for non-combustibility also guarantee fire safety performance for a cladding product, making it suitable for use.
Fairview’s range of cladding options, such as Vitracore G2 bonded aluminium panels and Vitradual solid aluminium panels, are tested to AS 1530.1 and AS 1530.3, and have been Codemark certified as non-combustible. These certifications render them suitable for use in construction – even where the new NCC is concerned.
Section J: Energy Efficiency
Section J outlines requirements for energy efficiency for commercial buildings, and requires that a building uses energy at a suitable level to its purpose and without unnecessary wastage. It aims to improve the performance of buildings, while recent changes also look to pre-empt future changes and more stringent environmental requirements slowly making their way into the construction industry, such as the requirement for solar panels, battery systems and electric vehicle charging.
The thermal performance of a building envelope improves the energy efficiency of the entire building, allowing for improved airflow and temperature regulation, and therefore a more comfortable space for occupants. Another benefit of thermal performance is its ability to provide inbuilt temperature control without reliance on excessive use of power, therefore reducing the building’s overall environmental impact. Some of the significant changes slated for Section J will surround thermal performance, including allowable thermal energy loads, heating and cooling in buildings.
When it comes to cladding compliance, cladding systems which can form a rainscreen or ventilated cavity will be ideal for meeting the NCC requirements. Ventilated cladding systems allow for airflow through a cavity behind the façade, effectively heating and cooling the building and reducing the need to use air conditioning systems, thus saving on power.
Fairview offers a range of solutions to improve energy efficiency and sustainability, and thus ensure cladding complies with the NCC. Fairview’s cladding products offer energy-efficient rainscreen systems, for improved energy efficiency of the building envelope. Fairview makes an additional contribution to sustainability with its ECOLOOP solution, which helps solve the environmental impacts of rectification works, recycling every part of ACP panels and repurposing the materials to divert 100% of product away from landfill. Learn more about ECOLOOP here.
Accessibility
For NCC 2022 more generally, our review confirms NCC 2022 adopts a new ‘consistent volume structure’ with a clause referencing system to create better consistency across all volumes. There are some clause name updates too; so, for instance, the performance requirement to prevent the spread of fire is now C1P2 rather than CP2. And although the NCC now looks different too, the re-organisation of content aims to improve the user experience, and make the Code more web-accessible.
Conveniently – as this transition to the new design evolves – the old clause numbers continue to be listed on the document’s right-hand side as an easy reference for code aficionados.
For those wanting to get into the granular detail of amendments specific to façade and wall cladding, please see our supplementary notes on Section C [Fire Resistance] and Part F3 [Roof and Wall Cladding] in the appendix to this article.
NCC 2022 Compliance Pathways
The NCC sets out a list of both all-encompassing and specific requirements surrounding the spread of fire, managing rainwater impact and weatherproofing, ventilation, sound transmission and energy efficiency.
To meet NCC requirements, products can either be considered a ‘Performance Solution’, a ‘Deemed to Satisfy Solution’ or, in some cases, a combination of both.
For a cladding system to be considered a Performance Solution, it must meet all NCC performance requirements and be verified to do so using expert judgement. Performance solutions factor in all possible outcomes for the building (for example, for a ventilated façade system, factoring in different temperature needs for different occupants).
Deemed to Satisfy Solutions still need to meet the NCC requirements, but by a more simple system in which they meet the specific criteria of the Deemed to Satisfy provisions, without considering the complexities of certain situations and how they may impact a product’s effectiveness. Deemed to Satisfy Solutions therefore allow for more compliance loopholes, but by discerning the durability and
safety of an individual cladding product, as well as which other standards it complies to, specifiers can still choose Deemed to Satisfy products that will effectively protect and sustain the building.
These performance requirements assess the whole cladding system and its ability to do its job – that is, protect and enhance the building it envelopes.
What about Cladding Compliance in 2023 and beyond?
The NCC continues to evolve as new industry issues or needs come to light, and to factor in shifting priorities, such as the move towards holistic sustainability. This means architects, specifiers and installers will need to watch closely for changes which may impact their use of certain cladding products. The cladding industry itself will also need to watch, learn and evolve along with the NCC to ensure products can be used on new projects moving forward. Specifiers will need to check the specifications of the cladding they use – both the material itself and the cladding as a complete system – to ensure it is suitable, and stay up-to-date with latest amendments to make sure they continue to use compliant products.
The NCC 2022 is now in effect as of May 2023, but more updates are anticipated beyond this date, so it is crucial to watch for these.
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Appendix:
Section C Fire Resistance
The non-combustible exclusions under C2D10(4) (previously C1.9d) have been significantly extended, including:
◦ Isolated packers, fixing accessories
◦ Waterproofing/weather sealing materials for concrete joints or weatherproofing 250mm up from ground level
◦ Wall ties, reinforcing
◦ Paint and the like
◦ Adhesives, including tapes, associated with stiffeners for cladding systems
◦ Fire sealing for penetrations
There is a new clause, which lists products defined as non-combustible C2D10(5). This list includes concrete, stone, terracotta, ceramics and most common construction metals.
Bonded laminate concession C2D10(6)(g) has been amended to include a fixing requirement C2D15, that:
◦ BLMs externally must have all layers of cladding mechanically supported or restrained to the supporting frame
Part F3 – Roof and wall cladding.
These changes are quite significant as they introduce Deemed to Satisfy Provisions for weatherproofing. Previously weatherproofing has relied on performance requirements only. Some of these new clauses that achieve the performance requirement are:
○ F3D3 – sarking type material used for weatherproofing of roofs and walls must comply with AS 4200.1 and AS 4200.2
○ F3D5 – external wall cladding must comply with … metal wall cladding: AS1562.1
To provide more detail on AS1562.1, this is primarily a structural and corrosion standard with some weatherproofing discussed in capillary action, minimum overlaps and flashings. The main content relating to cladding is:
○ Aluminium to comply with AS1734, be 5251 or 5052 grade and at least 0.7mm thick
○ Fastenings such as clips, brackets and washers shall be made from sheet aluminium in 3000 or 5000 series. No stainless screws.
○ Designed in accordance with AS1170.2 to resist wind actions
○ Design documentation to include profile, dimensions, spans, fasteners
○ Installation includes following design documentation, minimum end laps, and flashings around all projections through the cladding
○ Wind pressure testing to be conducted to AS4040.2 and 4040.3 for non-cyclonic and cyclonic zones respectively, and shall match the design documentation
○ Appendix B is informative having some helpful tips on minimising water penetration from wind driven rain
