There are many factors one considers before selecting a material, product or system for any building project. Budget, compliance and product suitability are some of the important considerations in this decision-making process.

Unfortunately, the price becomes the most important consideration in many decisions. Is that the key factor that should influence your selection?

In this article we set about providing a detailed comparison of aluminium and steel when used in the manufacture of stair and platform systems.

Aluminium Vs Steel - Cost

1. Material Costs

As it happens with the manufacture of any product, the cost of raw materials has a direct impact on the price of the finished item. With COVID-19 adding even more volatility into the equation, the price of aluminium and steel is continually fluctuating with many factors such as global supply and demand, fuel and shipping costs, and labour shortages creating the highest raw material costs the industry has ever seen.

In the manufacture of metal stairs and platforms, typically aluminium and steel are the preferred material options. Stainless steel, although highly corrosion-resistant and strong, is very expensive compared to both steel and aluminium, and is, therefore, rarely chosen in industrial applications such as these, based on the high cost.

When comparing the production costs of aluminium versus steel, aluminium does almost always cost more, simply because of higher raw material pricing.

However, as you will see, this slight difference in material cost is actually a very small factor when it comes to fabricating stairways and platforms in either aluminium or steel.

2. Labour/ Installation/ Time Costs

In the example below, we have used the installation of an average sized platform (approx 2.4m x 2.0m) manufactured to gain access to lifts or HVAC units.

Even though KOMBI systems can be assembled by non-specialist trades, we have assumed the same hourly cost. In both scenarios we have allowed extra time taking into account breaks, placement of goods into location and other miscellaneous factors.

Note: These costs are based on real numbers from completed projects.

Cost comparison

The table above only represents labour costs. Please see ‘Additional Costs’ below, which may need to be considered for the final costing.

So, why is there such a huge difference in the time to install KOMBI modular systems compared to traditional steel stairways and platforms?

In a typical steel stairway and platform install, on-site cutting and welding is required. The steel components would also need either painting or treatments applied to them to protect them from rust and corrosion. All of these processes add hours of time onto the installation.

With KOMBI modular stairs and platforms, there is no on-site welding. The systems are simply and easily assembled using basic hand tools. As the systems do not require specialist trades, they can be assembled by your own personnel, which can also significantly reduce total labour costs.

These savings in labour time is where KOMBI modular aluminium stair and platform systems will more than make up for slightly higher material costs.

3. Additional Costs

Apart from the cost of labour, there can also be additional costs that may need to be factored in for steel stair and platform installs. Due to their weight, the majority of steel parts cannot be safely handled manually. This necessitates the need for heavy lifting machinery to be brought onto site, an extra expense which often gets overlooked during budgeting.

KOMBI components are lightweight aluminium, weighing approximately a third of steel, and can be easily manoeuvred into place without requiring any additional machinery.

Another cost saving area in regard to aluminium versus steel is delivery. The lighter the weight, the less you pay in transportation fees, which is particularly attractive if you are located in remote areas.

Aluminium Vs Steel - Corrosion

Aluminium is significantly less corrosive than steel. It requires no painting or coating for protection and it will last for many years exposed to the elements. A natural property of aluminium is a self-repairing oxide layer that protects the metal inside. This oxide layer prevents aluminium from rusting or developing a thicker oxide layer as some metals are prone to do.

On the other hand, steel is extremely corrosive, requiring regular and ongoing painting or treatment to protect it from rust and corrosion, and ensure longevity.

This adds to the lifetime cost of the steel system, far in excess of the original supply price.

Aluminium Vs Steel - Strength

While steel is 2.5 times denser in is composition, providing a higher degree of strength, aluminium still has a very impressive strength to weight ratio and, when used in stair and platform applications, offers far above the required amount of strength.

Aluminium can also be engineered to provide high strength components that weigh much less than steel. Interestingly, if you were to manufacture stairs from a lighter form of steel such as mild steel, aluminium would produce a much higher strength product.

Note: All KOMBI systems are engineered industrial strength and very durable. They are built to withstand a live load of 2.5kPa and manufactured to Australian Standard AS1657.

Aluminium Vs Steel - Weight

Steel weighs approximately 2.5 times more than aluminium. This is due to its high density construction which, while offering a higher strength product, means that it is harder to handle, often increasing install times and incurring additional machinery costs.

Aluminium Vs Steel - Engineering

On every building and every project, compliance is supreme. When installing any system, it must be shown to meet the relevant Standards and Guidelines.

If installing traditional steel stairs and platforms you will still need to provide documentation to ensure compliance with Australian Standards. This will require the appropriate authority to inspect and certify that these systems are installed correctly and that their construction is suitable. Yet another expense!

With KOMBI systems, we have already done the hard work for you. All KOMBI stairs and platforms are pre-engineered to comply with Australian Standard AS1657.

You can also rest assured that even if custom designs are required our Design and Technical Teams can ensure you are supplied with compliant systems.

Aluminium Vs Steel - Lifetime Costs

While highlighting the many benefits of aluminium compared to steel in stair and platform applications, it is also very important to ensure you concentrate on installing fit for purpose systems and products that will pass the test of time.

Rather than focusing purely on initial cost, you must be sure the systems you install are compliant, robust and effective. In this competitive world, pricing is quite often the major driver in decision-making but this can frequently prove to be of short-term benefit.

Make sure this is not your only consideration and you factor in the other associated costs that all contribute to the lifetime cost of the system.

Summary

While steel may be inherently strong, and often assumed to be cheaper, aluminium is an extremely practical and cost-effective material in the application of platforms and stairs. As we have set out, there are a number of factors, beyond the initial supply costs that have a significant impact on the final total cost of the system, both upfront and throughout its lifetime.

Aluminium is lightweight, modular, strong and durable, and for these reasons, remains the standout choice of material for all of our KOMBI stair and platform systems.