Aluminium Composite Panels

Back in 2014 a fire started in Melbourne’s Lacrosse tower that took less than 15 minutes to rise several stories due to the cladding used on the building. After investigations it was decided that the main reason for the fire spreading so quickly was due to the aluminium composite panels used for cladding the building.

 

What is an aluminium composite panel?

An Aluminium Composite Panel, or ACP, is a type of sandwich panel, that consists of a lightweight core and has two aluminium sheets coating the outside. These sandwich panels have a large variety of applications including aircraft, other transportation vehicles and building and construction. They allow for high quality, low weight designs which are essential is many modern-day constructions. An aluminium composite panel consist of two thin coil-coated aluminium sheets bonded to a non-aluminium core and is mainly used for architectural cladding in buildings, but it does have other uses in the industry.

What kind of ACP was used on the Lacrosse tower?

The exact material used in the Lacrosse tower is known as Alucobest, a Chinese aluminium composite panel that uses a polyethylene centre. The product has won many awards for excellence in terms of being lightweight and is far less expensive than their competitors similar products.

However, while the product is incredibly cheap compared to other products due to its polyethylene centre it is highly flammable. Back in 2010 CSIRO conducted combustibility tests on Alucobest only to find it burn up in less than 2 minutes of test commencement. In order to pass for eligibility on high rise buildings composite panels must burn for at least half an hour to ensure fires spread slower and there is more time for occupants to react and get to safety. Therefore, Alucobest was never suitable for the Lacrosse building and never should have been approved. This isn’t to say the material should never be used, as it is suitable for smaller dwellings and is a cost effective option.

What alternatives are there for high rise buildings? 

There are so many substitutes available ranging from quality and price, however, it is important that for high rise buildings aluminium composite panels to be classified as either Fire Retardant (difficult to ignite) or Non-combustible and pass the AS1530.1 test to be certified by the Australian Standards.  One such product includes an Australian owned product called AlucobondPLUS. It is one of the leading products in aluminium composite material for fire performance, meeting all Australian fire safety requirements as well as European requirements and achieving Group 1 results in the international organisation of standardization’s ISO9705 test. However, it only JUST meets the requirements as long as it is used under stringent conditions, including sprinklers etc. ALCDEX A1 is another example of a composite panel that is AS1530.1 Certified as a ‘Non-Combustible Aluminium Composite Material’ and can be used where a non-combustible material must be used as per the Building Code of Australia (BCA).

Other products include those with fire retardant cores, which is a mineral filled thermoplastic core between the two sheets of aluminium. It offers similar benefits to polyethylene core composite panels with the exception that it offers compliance with many worldwide fire codes.

It is important to note that no aluminium composite panel is completely fire proof, only code compliant. Eventually all aluminium will melt if exposed to fire long enough, however being deemed fire-rated approved means it’s suitable to live in. So, if you’re planning to develop or live in a high rise building in the future be sure to enquire as to the cladding type used (as well as materials used in other aspects of the building) and ensure it passes Australian Standards and complies with Building Codes of Australia.

 

 

Further Information Can Be Found:

https://www.engineersaustralia.org.au/portal/news/investigation-combustibility-breach

http://www.architectureanddesign.com.au/news/builders-investigate-use-of-flammable-aluminium-cl

https://www.sgi-architectural.com.au/news/pe-polyethylene-vs-fr-fire-retardant-core/

https://certmark.org/articles/2017/06/cmi-advisory-note-aluminium-composite-panels-acp-fire-risk-australia-new-zealand/

http://www.alcadex.com.au/images/tabs/catalogue.pdf