RECLADDING, REFURBISHMENT AND RECTIFICATION OF EXISTING COMMERCIAL BUILDINGS:THE SOLUTION FOR NON-COMPLIANT WALL SYSTEMS

Significant cause for alarm regarding the state of building façade standards has been raised in recent years, after a series of internationally notable, catastrophic events regarding both building occupant safety and structural integrity. The Grenfell Tower fire of 2017, along with the Lacrosse Tower (2014) and Neo200 building fires (2019) in Melbourne are three examples of such events,all of which utilised Aluminium Composite Panels (ACPs) to some extent.1 Most critically, the types of ACP specified in these buildings contained a combustible polyethylene core.2

In Australia, the release of the 2019 National Construction Code saw the overhaul of building standards related to fire resistance and stability, including the continued inclusion of section C1.9 after it was originally introduced as an amendment to the NCC 2016 in March 2018. Most critically to the aforementioned events, and in an effort to prevent similar occurrences in the future, Section C1.9(a) specifies that all external walls of TypeA or B construction (all Class 2, 3 or 9 buildings greater than 2 storeys, and all Class 5, 6, 7 or 8 buildings greater than 3 storeys) must be non-combustible, applied to materials as defined by AS1530.1, or as applied to a system “constructed wholly of materials that are deemed non-combustible.”3 Furthermore, all external wall componentry, including “the façade covering, framing and insulation” is included within this requisite as per clause (i).4

Such events have affected all stakeholders within the building

industry. From the bottom up, there has been a marked loss in consumer trust, while insurers are raising premiums or limiting their own liability from the top down.5, 6 As such, there is significant room for improvement – not only through smarter, code-compliant specification moving forward, but also through the recladding, rectification and refurbishment of existing buildings that may utilise combustible cladding systems. Insulated panels made from an aluminium, zinc or copper outer-material with a polyethylene (PE), polystyrene (XPS/EPS), polyurethane (PUR) or polyisocyanurate (PIR) core should be avoided for façade specification in Type A or B construction,7 but alternative insulated panels, such as those containing a rock wool (also known as mineral wool) are valid prospects, as are solid sheet materials such as solid aluminium or ceramics. The potential exists not only to correct a hazardous specification decision, but also to improve passive envelope performance across a wide range of considerations.

In this whitepaper, we take a look at the rising demand for insulated panels and the related circumstances that led to the current crisis, along with the ratified conditions for building compliance. Now more than ever before, Australian designers and specifiers must be able to relay relevant information back to their clients, concerning the new requirements of the NCC 2019 and the opportunity to upgrade building stock and improve energy efficiency.

THE CHANGING LANDSCAPE OF CLADDING COMPLIANCE

COVER IMAGE: Latrobe University Sports Stadium. ASKIN Metric Roof & ViviD Walls with Volcore®, Colorbond skins with Bronze Rosanna RibsABOVE: Alamanda College. Recladding - ASKIN Exteriors - Non-combustible façade system with Copper Penny Alfrex solid aluminium

AUSTRALIA’S CURRENT POSITION

The popularity of lightweight cladding systems is attributable to their high functionality and relative affordability, ultimately leading to a pivot away from heavy masonry systems that characterised much of Australian architecture prior to their introduction.Nonetheless, lightweight cladding systems still come under regulatory scrutiny. As with any chosen cladding system, there are specific performance requirements that must be met in regards to weatherproofing, structural integrity, thermal performance and a range of fire-related considerations.

Audits that followed the recent events have uncovered more than a thousand buildings with combustible cladding issues in Victoria alone.8 Even the Neo200 building was deemed to be “safe for occupation” with “no further action required” in a 2016 audit,9 considering that only 10 per cent of its façade was combustible aluminium composite material.10

That fact alone should signal more needs to be done, and stems from the nature of the NCC’s deemed-to-satisfy provisions – or rather, the emphasis that is often placed on active deemed-to- satisfy solutions (such as a smoke alarm) over passive equivalents (such as a non-combustible façade system), which represent a more significant initial cost output.

Ensuring occupant safety and building integrity is not only dependent upon compliant products, but also compliant specification and installation. Certain aluminium composite panels, for instance, may still be compliant for use in specific circumstances despite being unsuitable for use in multi-rise

commercial, medium and high density building (also known as Type A or B) construction – their use is dependent not only on their individual properties, but also on their role in a greater system. One study into the Grenfell tower fire noted, “the qualitative demonstration of PIR ignition by flaming drips of PEfrom [aluminium composite material],” thus serving as a warning for such, “since one component can interact synergistically or antagonistically with any other.”11 In addition to Grenfell, Lacrosse and Neo200, the inadequate specification and installation of ACPs caused or contributed to eight out of ten international external- cladding fires between 2010-2016.12

While the affected buildings have been mostly multi-residential, the audits taking place locally have extended beyond multi-res to encompass buildings in any Class 2, 3 or 9 building, and anyClass 4 portion of a Class 9 building.13 These Classes, determined by the ABCB, encompass multi-res properties in addition to other forms of long or short-term residences and buildings of a public nature, such as hospitals and stadiums.

With so many properties potentially affected by improper specification, rectification and refurbishment is by-and-large the correct way forward – at-risk buildings cannot remain as they are, and demolition is an unviable option from both a cost and an environmental perspective. Rectification allows building owners to safeguard their property and tenants in regards to the newly established performance requirements of the NCC 2019, while also adding value in the long term.

Melbourne Arena. ASKIN ViviD Walls with Volcore® Cladding system and Colorbond Metallic colours

CODE COMPLIANT FAÇADE AND WALL SYSTEMS

One of the primary issues identified by the ABCB’s regulation impact statement into the circumstances leading to the specification of non-compliant cladding is a simple lack of understanding: “For designers, information provided by suppliers may not be conclusive in demonstrating compliance with the NCC, compromising their ability to choose appropriate cladding products.”14 Given the prevalence of deemed-to-satisfy testing and reports, building owners and specifiers should look for products and or complete wall systems that are clearly labelled as having passed AS1530.1. If a manufacturer has labelled a product only with ‘limited combustibility’, then it has not passed the Australian Standards for non-combustibility and should not be treated as such when attempting to meet the requirements set out in C1.9. These instances do not necessarily occur out of malicious intent; they more typically derive from a product having passed a set of standards outside of Australia that do not translate to the Australian market.

As previously mentioned, combining elements that individually may pass AS1530.1 may not result in a combustion-proof façade after taking into account the complementary elements that the end façade is composed of. AS5113:2016 was introduced as a means by which to test whole façade systems against their ability to limit the spread of fire, and should be considered as a means of certification useful in further ensuring occupant safety and building integrity.

Beyond combustibility, recent enquiries following Grenfell have also focused on the toxicity and amount of smoke produced by combustible materials in the event of a fire – the primary cause of death for building occupants. While specifiers cannot control the materials or personal effects that owners and occupiers will bring into a building, they can control what goes into a building’s construction. Self-education on the matter is important for all specifiers who are designing spaces fit for occupancy: studies have shown the significant non-combustibility of glass wool and stone wool equate to very low fire toxicity, while polyurethane foam based products are highly toxic and require only 1kg to burn in under-ventilated conditions to be lethal for anyone within a 100m3 space.15

In Australia, C1.9(e) dictates that the Smoke-Developed Index of any bonded laminate material does not exceed 3 (as determined by AS1530.3), although specifiers should keep in mind this represents the minimum standard.

Furthermore, designers and specifiers must still ensure their building envelope meets the performance requirements for weatherproofing (as specified by NCC FP1.4 and FP1.5), as well as energy efficiency. With the updates to the NCC,construction systems that were sufficient only a few years ago may no longer be appropriate for new construction regarding thermal performance, selection of colour, thermal bridging or air tightness. For those that did meet previous compliance, it is worth considering the benefits of bringing them up to date, improving safety, passive performance and increasing building value in the long run.

Latrobe University Sports Stadium. ASKIN Metric Roof & ViviD Walls with Volcore®, Colorbond skins with Bronze Rosanna Ribs

MINERAL WOOL INSULATED PANELS AND SOLID ALUMINIUM PANELS

ASKIN | PERFORMANCE PANELS

Education is the most critical step towards ensuring market compliance with the NCC requirements and correct install methodology for façade systems. Any chosen system, whether it is a solid aluminium system or insulated panel system, must pass all compliance requirements to do with fire performance, installation, energy efficiency and weatherproofing.

In this light, insulated panels remain a simple and cost- effective way to meet the NCC requirements given adequate specification and installation. To avoid the pitfalls of combustible ACPs, mineral wool insulated panels are a proven alternative given they; meet the NCC 2019 DTS provisions in C1.9(e) for non- combustible building elements in Type A and B construction; are capable of achieving a Group 1 fire rating in accordance with AS5637 as required by NCC 2019 C1.10; and release minimal levels of smoke and toxicity during a fire.

As a lightweight construction, mineral wool insulated panels also remain a highly viable option for thermal performance, wind loading and weatherproofing. This simplifies the design and construction process for added security and time savings, making recladding and refurbishment a significantly simpler process than it would be otherwise.

Many issues associated with facades go unidentified until the damage has already been done. Specifiers must take the utmost care with products and systems included from the outset in order to ensure occupant safety and building integrity, and work with companies that are invested in both developing new technology and in the development of projects, from concept to completion.

ASKIN Performance Panels are the largest manufacturer and installer of insulated, fire rated and architectural façade systems across Australasia. Their Volcore panel range is a non-combustible insulated panel system, comprising a non-combustible mineral wool core sandwiched between two steel layers. The ASKIN Volcore Panel has been certified as non-combustible to the performance requirements of Volume One of the NCC 2019, section C1.9(e). Its mineral wool core makes it extremely thermally efficient, with R-values up to 5.2, whilst providing significant sound absorption levels. Quick to install, Volcore is available in lengths up to 13.5m and in a range of profiles, finishes and colours.

For more information, visit ASKIN’s website below.www.askin.net.au

ABOVE: Maribyrnong Secondary College. Recladding works - ASKIN Volcore® ViviD Panels in Colorbond sparkling white and matching Alfrex solid aluminium façade system

Melbourne Girls College. Rectification - ASKIN Exterior Volcore® Panels in Colorbond Citi and matching Alfrex solid aluminium façade system

REFERENCES1 Koob, Simone. 2019. “How Hundreds Of Lives Were Thrown Into Chaos When Neo 200 Caught Fire”. The Age. https://www.theage.com.au/national/victoria/how-hun-

dreds-of-lives-were-thrown-into-chaos-when-neo-200-caught-fire-20190429-p51i62.html.2 Hanmer, Geoff. 2019. “Cladding Fire Risks Have Been Known For Years. Lives Depend On Acting Now, With No More Delays”. Architectureau. https://architectureau.com/

articles/cladding-fire-risks-have-been-known-for-years-lives-depend-on-acting-now/.3 Australian Building Codes Board, 2019. NCC 2019 Building Code of Australia – Volume One, Commonwealth of Australia and the States and Territories of Australia,

Canberra, p. 656.4 Australian Building Codes Board, 2019. NCC 2019 Building Code of Australia – Volume One, Commonwealth of Australia and the States and Territories of Australia,

Canberra, p. 67.5 Longitude Insurance. n.d. “The Past, Present And Future Of External Cladding”. Accessed October 27, 2019. https://www.longitudeinsurance.com.au/images/content/

longitude_insurance_the%20past_present_future_cladding.pdf.6 Chubb Insurance Australia Limited. 2018. “Aluminium Composite Panels July 2018 Update”. Risk Bulletin. https://www.chubb.com/au-en/_assets/documents/

chubb-risk-bulletin--aluminium-composite-panels.pdf.7 “Combustible Cladding Regulation”. 2018. NSW Department of Planning, Industry and Environment. https://www.planning.nsw.gov.au/Policy-and-Legislation/Buildings/

Combustible-cladding.8 Lockrey, Simon, and Trivess Moore. 2019. “Flammable Cladding Costs Could Approach Billions For Building Owners If Authorities Dither”. The Conversation. https://the-

conversation.com/flammable-cladding-costs-could-approach-billions-for-building-owners-if-authorities-dither-118121.9 Koob, Simone, Robyn Grace, and Liam Mannix. 2019. “’Same As Grenfell Tower’: Cladding Fears As Fire Rips Through Melbourne CBD Apartment Building”. The Age.

https://www.theage.com.au/national/victoria/same-as-grenfell-tower-cladding-fears-as-fire-rips-through-melbourne-cbd-apartment-building-20190204-p50vgl.html.10 ABC News. 2019. “Melbourne Apartment Tower Fire Fuelled By Combustible Cladding On Spencer St High-Rise”, 4 February. https://www.abc.net.au/news/2019-02-04/

spencer-street-apartment-fire-melbourne/10776018.11 McKenna, Sean T., Nicola Jones, Gabrielle Peck, Kathryn Dickens, Weronika Pawelec, Stefano Oradei, Stephen Harris, Anna A. Stec, and T. Richard Hull. 2019. “Fire

Behaviour Of Modern Façade Materials – Understanding The Grenfell Tower Fire”. Journal Of Hazardous Materials 368: 115-123. doi:10.1016/j.jhazmat.2018.12.077.12 Australian Building Codes Board. 2016. “Non-Compliant Use Of External Cladding Products On Buildings”. Regulation Impact Statement. Australian Government, States

and Territories of Australia. https://www.abcb.gov.au/-/media/Files/Resources/Consultation/RIS-External-Cladding.pdf.13 Environmental Planning And Assessment Amendment (Identification Of Buildings With External Combustible Cladding) Regulation 2018. 2018. https://www.legislation.

nsw.gov.au/2018-499.pdf: NSW Government.14 Australian Building Codes Board. 2016. “Non-Compliant Use Of External Cladding Products On Buildings”. Regulation Impact Statement. Australian Government, States

and Territories of Australia. https://www.abcb.gov.au/-/media/Files/Resources/Consultation/RIS-External-Cladding.pdf.15 Stec, Anna A., and T. Richard Hull. 2011. “Assessment Of The Fire Toxicity Of Building Insulation Materials”. Energy And Buildings 43 (2-3): 498-506. doi:10.1016/j.

enbuild.2010.10.015.

All information provided correct as of March 2020