By Engineer Arnon Kfir, April 13, 2021
Since the beginning of the COVID-19 pandemic in April 2020, we have seen a sharp and relatively rapid increase in aluminium prices, rising from around $1,480 per tonne to approximately $2,300 per tonne.
Many believe that the main factors behind the rise in metal prices, particularly non-ferrous metals, have been labour shortages, increased transportation costs, especially sea freight, reductions or interruptions in global production, and speculative market activity focused on the limited stock that remained available.
The global uncertainty during the first months of the pandemic, together with reduced production output, caused a significant decline in inventory levels held by manufacturers and suppliers. The shortage of readily available raw materials was felt almost immediately, not only in the metals market but across many industries.
China is one of the world’s largest consumers of metals. In recent years, China has also become highly influential in global industrial metal trading. One of the best-known international metal trading centres is the London Metal Exchange, or LME.
As a result, developments in China can have a significant effect on the global economy.
At the time this article was written, the outlook was not particularly encouraging. China was among the first countries to recover from the COVID-19 crisis and was reporting expected economic growth of more than 2% during 2021.
This meant that a large proportion of what China produced could also be consumed domestically. That situation was already contributing to increasing global demand, rising prices, reduced inventory levels, and longer delivery times.
The Situation in Israel
At the beginning of the pandemic, Israel still had sufficient inventory levels of both ferrous and non-ferrous metals, including aluminium and copper, through the spring of 2020.
However, uncertainty regarding the future of the Israeli economy caused importers to reduce their stock levels.
From the early summer of 2020 onward, the Israeli market began experiencing price increases in both ferrous steels and non-ferrous metals.
So what happens in Israel when global prices rise but customers are unable or unwilling to pay more?
In many cases, suppliers offer a different material that is cheaper and more readily available in order to avoid losing the sale.
In Israel, as is often the case, people are quick to find an alternative solution. If material X is unavailable, a substitute such as X1 or Y may be offered, often accompanied by the phrase:
“It doesn’t matter, as long as it’s similar.”
Importers began searching for available stocks of aluminium coils and sheets that could be sold as flat material, as had been done previously.
Indeed, several suppliers managed to find such alternatives.
What Does This Mean for Building Cladding?
Recently, I have received complaints from customers, developers, and manufacturers who purchased aluminium sheets or coils for processing and manufacturing exterior building cladding components.
The complaints have been fairly similar.
Customers report that the material does not behave the way they are used to, particularly during processing on rolling, bending, and cutting machines.
Following checks I carried out at the end of March 2021, I found that aluminium sheets, coils, and cladding products were being imported into Israel using alloy series that had not previously been commonly used in the Israeli cladding market.
Examples include aluminium alloys from the 1050 and 5005 series, sometimes supplied at a thickness of only 2.0 mm, with approximately 1% magnesium.
In my view, these alloys are less suitable for manufacturing certain cladding components at a thickness of 2.0 mm because their material properties are inferior to aluminium alloys such as 5052 or 5754 ALMG3.
Using aluminium that is too thin or made from an alloy that is unsuitable for the intended product can affect:
- Appearance
- Structural strength
- Dimensional stability
- Long-term durability
- Overall performance of the finished cladding system
What Is the Problem with These Alloys for Roofing and Cladding?
For many years, Israel’s aluminium cladding market maintained relatively high standards and generally followed European practices.
Manufacturers usually selected aluminium alloys according to their intended use.
For example, when producing aluminium cassette wall cladding, it is extremely important that the aluminium sheets remain flat over time.
The material should also be:
- Free from excessive internal stresses
- Dimensionally stable
- Suitable for Mediterranean environmental conditions
- Properly coated or painted
- Appropriate for long-term external use
For cassette cladding, the aluminium should ideally be supplied in a stress-free condition to reduce the risk of distortion after fabrication.
The Importance of Magnesium Content and Material Thickness
For example, alloys such as 1050 and 5005 have a relatively low magnesium content.
These alloys were also used in cladding applications in the past, but when they were used, the minimum material thickness was often around 3.0 mm.
By comparison, with the more advanced alloys commonly used in Israel in recent years, a thickness of 2.0 mm can often be sufficient when the correct alloy and engineering design are used.
For FALZONAL roofing systems, aluminium from the 3003/3005 alloy series should continue to be used.
For aluminium cassette wall cladding, the recommendation is to continue using 2.0 mm pre-painted aluminium with a magnesium content of at least approximately 3.0%, where this is appropriate for the design specification.
Why the Correct Aluminium Alloy Matters
In Israeli construction projects, using composite materials or aluminium alloys that are unsuitable for the intended application can quickly become visible in several ways.
Problems may appear both in the appearance of the cladding and in the physical behaviour of the material itself.
Over the past decade, the Israeli market has become accustomed to relatively high-quality aluminium products for building cladding.
This has not always been the case with steel cladding products.
For this reason, particular care should be taken during periods of supply shortages to avoid using lower-grade substitutes simply because the preferred material is unavailable.
If an unsuitable material is installed and fails, the result may eventually be removal and complete reinstallation of the cladding.
How Can You Make Sure You Receive the Material You Ordered?
The first step is to ask the supplier to provide a Certificate of Conformity, or COC, together with the delivery documentation.
When dealing with a new supplier or dealer, it is advisable to request not only the COC but also a signed declaration confirming that the supplied material matches the information stated in the certificate.
Where appropriate, the information should also be verified and confirmed in Hebrew so that the material specification can be clearly compared with the actual supply.
If there is any doubt, both the material itself and the accompanying documentation can be inspected and verified.
Our Recommendation
During periods when high-quality materials are frequently replaced with substitutes because of availability and price pressures, do not install even a single panel before confirming exactly what the panel is made from.
The cost of checking the material in advance is far lower than the cost of dismantling and replacing an unsuitable cladding system after installation.
About the Author
Arnon Kfir is an engineer and specialist in roofing systems and building envelopes. He conducts engineering arbitrations and prepares professional expert opinions for court proceedings. He is registered on the list of court-appointed experts.
Contact: 052-3564892