Home / Guides / Corflute vs Foam Board: What Corflute Is and When to Use Each

Corflute is a lightweight, waterproof fluted polypropylene board made for outdoor signage. Foam PVC is a solid, rigid board better suited to indoor displays. Compare thickness, weight and durability to choose the right option Corflute for outdoor signs, foam PVC for indoor presentation.

Corflute is a twin-wall corrugated polypropylene sheet, typically 5 mm thick, with hollow flutes between two plastic faces. It is lightweight, waterproof and affordable, making it ideal for real estate, election, event and construction signs.

Foam PVC (Foamex) is a solid, smooth PVC board with no flutes, giving it a cleaner, more polished finish. Choose Corflute for outdoor, temporary or staked signage, and foam PVC for indoor signs where appearance and a smooth finish matter most.

• Corflute is corrugated polypropylene sheet: two plastic skins with hollow flutes between them, usually 5 mm thick.
• Corflute is fully waterproof and will not swell, rot or delaminate, which is what makes it the default short-term outdoor sign board.
• Foam PVC is solid and smooth-faced, so it prints flatter than corflute and shows no flute shadow under raking light.
• A 5 mm corflute sign takes an H-stake or an A-frame directly; foam PVC splits at the stake and is not made for it.
• Corflute costs roughly half what foam PVC costs per square metre at the same thickness, so budget outdoor runs go to corflute nearly every time.

Corflute is the Australian trade name for corrugated polypropylene sheet two thin plastic skins separated by hollow flutes. It is available in 3 mm, 5 mm and 10 mm, with 5 mm being the most common for signage. Lightweight, waterproof and resistant to rotting and delamination, it is widely used for outdoor signs. Overseas, you may see it sold as Coroplast, Correx or fluted board.

A printed corflute sign exposed to full Australian sun will typically show visible fading and UV wear within 6–12 months. Signs kept in shade or under cover can last considerably longer. For signage expected to remain outdoors for more than a year, aluminium composite is a more durable choice.

It depends on the material. Foam PVC, sold under names such as Foamex, Palight and Forex, is closed-cell and waterproof, making it suitable for signage. Paper-faced foam core, commonly used for presentations and artwork, is not waterproof and can delaminate when wet. In sign production, “foam board” generally refers to foam PVC.

Each material has different strengths. Corflute is stiff along the flute direction but more flexible across it, while foam PVC has consistent rigidity in both directions but is heavier and can bow in high heat. For staked ground signs, 5 mm corflute is usually the practical choice. For flat wall-mounted panels, 5 mm foam PVC provides a cleaner, more rigid finish.

For most signs, run the flutes vertically. This is especially important for ground-staked signs, where the stakes need to align with the flutes for secure fixing. For other installations, run the flutes along the longest unsupported span to improve rigidity. Flute direction must be specified before production.

Choose corflute for outdoor, temporary or staked signage where low cost and weather resistance matter such as real estate boards, event signs, construction notices and wayfinding. Choose foam PVC for indoor displays, wall-mounted signage and close-up applications where a smooth, professional finish is more important. For long-term outdoor signage, aluminium composite is the better upgrade.