Steel vs Aluminum Long-Span Truss — 5 Key Points to Help You Choose

Some say aluminum trusses are lightweight and premium, while others argue steel trusses are cost-effective and durable. In fact, there is no absolute "better" option — only what fits your application best. Below we break down the differences between the two truss types across 5 core dimensions: load capacity, self-weight, cost, corrosion resistance, and transportation & assembly.

1、Load Capacity: Significant Gap in Heavy-Duty Scenarios

Steel Truss (Q355B)：Ideal for heavy-duty long-span applications. All our steel trusses come standard with Q355B low-alloy steel pipes, delivering 40% higher load capacity than ordinary carbon steel trusses. For single spans of 20–40 meters, they can simultaneously support LED video walls, line array speakers, and a full set of stage lighting fixtures — no extra support columns needed to compensate for load limits, ensuring unobstructed stage views and complete presentation effects.

Aluminum Truss (6082-T6)：As a high-strength grade in the aluminum alloy family, 6082-T6 trusses in standard sizes can support medium-to-large stage lighting and medium audio equipment, making them the mainstream choice for small-to-medium span events. However, limited by the inherent properties of aluminum alloy, for high-density heavy-duty requirements such as spans over 20 meters, heavy LED video walls, and multiple line array speaker sets, the truss cross-section must be significantly enlarged or intermediate support columns added, leading to higher costs and more site constraints.

2、Self-Weight & Site Requirements: Lighter Is Not Always Better

Steel Truss：With the same specifications, the self-weight of steel trusses is approximately 3 times that of 6082-T6 aluminum trusses, imposing certain requirements on ground load capacity. They are more suitable for sites with sufficient ground conditions, such as outdoor flat ground, ground-floor venues, and stadiums. On the flip side, the greater self-weight brings higher overall rigidity and wind resistance stability. In strong outdoor winds, the sway amplitude is far smaller than that of lightweight aluminum trusses, providing a higher safety margin.

Aluminum Truss：Light weight is its core advantage. With the same specifications, it weighs only about 1/3 of steel trusses, placing almost no stress on ground load capacity. It is almost always the first choice for sites with limited ground load capacity, such as upper-floor exhibition halls, high-rise hotels, and indoor ceiling installations.

3、Overall Cost: Up to 50% Savings for Equivalent Load Capacity

Steel Truss：The cost advantage of steel trusses becomes even more pronounced in heavy-duty projects with spans over 20 meters. No extra support columns or oversized truss upgrades are required, resulting in substantial budget savings for the complete system.

Aluminum Truss：As a high-strength aluminum alloy, its raw material cost is inherently higher than standard aluminum grades, leading to higher unit prices for both purchase and rental. For long-span heavy-duty projects, costs will rise further as oversized truss specifications and additional support columns are required to meet load requirements.

4、Corrosion Resistance & Service Life: Different Solutions for Different Needs

Steel Truss：Carbon steel is inherently prone to rust and requires professional anti-corrosion treatment, but this does not mean a short service life. Our steel trusses adopt a **sandblasting + powder coating** anti-rust process. With regular indoor use and proper maintenance, the service life can reach 8–10 years; for outdoor open-air use with regular touch-up painting, it can last 6–8 years. For long-term fixed outdoor use, a custom hot-dip galvanized version is available with a service life of over 15 years, fully meeting the reuse needs of most projects.

Aluminum Truss：Aluminum is naturally rust-resistant and requires no additional anti-corrosion treatment. It has low wear and tear after long-term repeated use, works both indoors and outdoors, and is hassle-free for daily maintenance.

5、Transportation & Assembly: Lightweight Does Not Equal Higher Efficiency

Steel Truss：Individual sections are heavier, but our beam trusses adopt a single-piece modular segmented design that allows tight stacking on trucks, delivering high loading efficiency for long-haul logistics. This makes them more cost-effective for large projects and long-distance transportation. On-site assembly uses bolt-on connections with no hot work required. Paired with our servo electric cylinder lifting system, there is no need to rent a mobile crane, ensuring high overall assembly efficiency while saving on hoisting costs.

Aluminum Truss：Individual sections are lightweight and easy to handle manually, making them suitable for small projects and short-distance transportation. However, due to their structural design, stacking loading efficiency is low, and volumetric shipping costs are not favorable for large projects with long-distance transportation.

If your project involves small-to-medium spans, upper-floor indoor venues, and mainly light equipment like stage lighting, 6082-T6 aluminum trusses are a suitable choice.

However, for spans over 20 meters, heavy LED video walls / line array speakers, outdoor open-air events, or projects aiming to control overall budget, Q355B steel trusses offer higher cost performance and greater reliability.