Trench boxes, also known as trench shields, are invaluable resources for construction crews handling excavation projects. These robust structures comprise sturdy plate walls and bars installed within trenches to protect workers in the event of a collapse. Trench boxes can also improve the stability of the trench walls using adjustable spreaders that you can modify according to the size of the trench. 

You can find trench boxes in various materials, though the most common are steel and aluminum. These box types are popular due to their weather resistance, preventing them from corroding or warping. Aside from this characteristic, steel and aluminum trench boxes have many differences.

This guide will discuss the two types of trench boxes and the differences between them to help you decide which to use.

Differences of Steel and Aluminum Trench Boxes

When choosing a trench box for your job site, it’s essential to select the one that best serves your project needs. You can determine the top choice for your company by assessing the differences between aluminum and steel trench boxes.

1. Durability

While aluminum and steel are both strong materials, steel is the more durable of the two due to its high carbon levels. Steel is exceptionally rigid, making it less likely to bend or dent when met with force or pressure. Aluminum is more malleable than steel, meaning it can easily bend into different shapes without cracking or breaking. However, it is more likely than steel to scratch or dent. 

Despite steel’s position as the most robust metal, it’s worth noting that aluminum has a better strength-to-weight ratio that makes it easier to handle.

2. Size

While trench boxes are available in various sizes, you can typically find specific heights and lengths to fit common needs. It’s crucial to consider your project specifications and trench size to ensure the box you choose is capable of supporting it.

You can usually find steel trench boxes in heights of 4, 6, 8 and 10 inches. Aluminum solutions are typically only sold in 6- and 8-inch-tall configurations, making steel trench boxes more versatile for protecting workers in both shorter and taller trenches.

Steel trench boxes can range from 8 to 24 inches long in increments of 2 inches. They also come in 28- and 32-inch-long varieties for longer trenches. Aluminum boxes usually go from 6 to 16 inches in increments of 2 inches. That means you might want aluminum trench boxes for smaller excavations and steel boxes for longer ones.

3. Weight

Aluminum trench boxes are known for their lightweight structures, making them easier to handle and less expensive to ship. Steel is a much heavier metal, getting its weight from its high carbon concentration. It is over twice as dense as aluminum, which makes it more durable.

4. Applications

Because aluminum trench boxes weigh significantly less than steel, they’re better suited for light-duty applications like small-scale trenching and excavation projects. Aluminum trench shields are also useful for shallow-earth applications and projects involving lightweight equipment like compact excavators and backhoes. They work well in tasks that require upward digging, such as pipe laying, cabling and manholes.

Steel trench boxes are the stronger and denser of the two, making them useful for large-scale projects like heavy-duty excavations. Their weight also makes them an excellent solution for jobs with challenging or uneven terrain. 

5. Cost

Price is always an important factor to consider when choosing a trench box for your job site. Steel is typically less expensive than aluminum per pound, though the cost of material is constantly fluctuating based on factors like supply and demand, material availability, and fuel costs. 

Though aluminum is the more expensive material, these trench boxes are faster and easier to install without the use of heavy machinery, so they may be more cost-effective in that regard. 

6. Resale Value

Because of their durability, steel trench boxes typically have longer life spans than aluminum boxes. As a result, they hold their value for longer, meaning you can earn a higher return on investment (ROI) if you ever choose to sell them. However, despite their tendency to dent and bend, aluminum trench boxes have greater corrosion resistance than steel, so these trench shields still have a good chance of lasting in the long term.

Rent Durable Trench Boxes at The Cat® Rental Store

You can rent steel or aluminum trench boxes for your next construction project at The Cat® Rental Store. We support our customers by offering an extensive selection of top-quality rental equipment featuring some of the industry’s latest technologies. We also deliver exceptional customer support, and our massive dealer network means we can provide on-demand rentals for all your last-minute product needs. 

Find your nearest location of The Cat Rental Store or reach out online to request a quote on one of our trench boxes.

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