ACM vs Aluminium: A Guide to the Best Materials for Road Traffic Signage

When specifying materials for permanent signage, there’s often a choice between solid aluminium and Traffic Grade ACM (Aluminium Composite Material). Both offer durability and outdoor performance, but each has unique characteristics that may make one more suitable than the other, depending on the project requirements.

At Ashby Trade Sign Supplies, we manufacture signs and sign components from both materials. This guide explores the benefits and limitations of each, helping you make an informed decision for your next installation.

Why We Prefer Aluminium for Many Sign Applications

Aluminium remains our preferred material for its balance of durability, fabricability, and recyclability.

• Durability: Unlike steel, which rusts and flakes, aluminium forms a stable oxide layer that resists corrosion and extends product lifespan, making it ideal for exposed or long-term signage.

• Versatile Finishing: Aluminium is compatible with powder coating, offering virtually limitless options for colours and textures.

• Flexible Fabrication: It can be laser cut, folded, curved, and welded, making it suitable for bespoke signage and complex shaping.

• Recyclability: Aluminium is nearly infinitely recyclable. Although its primary production is energy-intensive, recycling uses just 5% of that energy and involves no material degradation — aluminium retains its quality with each cycle.

• Sustainable Sourcing: We go further by sourcing billet from hydro-powered plants, helping reduce the environmental footprint of our supply chain.

Where Traffic Grade ACM Excels

While aluminium has long been the UK standard for traffic signs, Traffic Grade ACM is increasingly popular for its cost efficiency and reduced weight, without a compromise in performance.

• Purpose-Built for Road Use: This newer ACM variant is engineered for signage, offering excellent compatibility with reflective sheeting and reliable corrosion resistance.

• Lighter & Easier to Install: Its reduced weight simplifies installation and lowers transport-related emissions, this is especially valuable in high-volume or remote projects.

• Cost Advantage: ACM panels offer similar visual and structural performance at a lower price point than solid aluminium.

• Sustainability Measures: We’ve partnered with a specialist supplier who have developed a closed-loop system for their composite - all our off-cuts are collected and taken to their dedicated recycling facility for reprocessing into new materials.

• Anti-Theft Benefit: ACM’s low scrap value and harder-to-recycle nature make it less attractive for theft. Unfortunately, this is a real practical bonus in some environments.

While some local authorities still prefer solid aluminium for regulatory signage, many are now turning to Traffic Grade ACM for permanent signage in both urban and rural settings — especially where cost and logistics are key considerations.

Summary: Which Material Should You Choose?

Choose Aluminium if you need maximum structural strength, high-end finishes, or are working on bespoke or complex signage.

Choose Traffic Grade ACM when weight, budget, or anti-theft concerns are more pressing.

Both aluminium and composite road traffic signs can be found in our Component Shop. Please contact us for bespoke manufacture, or fill out an enquiry form on our Sign Systems pages.

If you’re unsure which is right for your project, our team is happy to advise. We have decades of experience supplying the UK sign trade, we can help you find the balance that best fits your needs.