Your Ultimate Guide to YELLOWtongue®, BLUEtongue® and REDtongue® Flooring

When choosing structural flooring, understanding the differences between tongue colours is essential. Each option within the STRUCTAflor® range is engineered for a specific purpose, providing strength, stability and performance to suit residential, commercial and light industrial applications.

STRUCTAflor® is an Australian-made, structural-grade particleboard flooring designed for both platform and fitted construction. It’s manufactured to meet AS/NZS 1860.1 standards and is trusted by builders nationwide for its durability, strength and ease of installation.

Available in general-purpose, termite-treated and radiant barrier options, STRUCTAflor® offers a complete solution for flooring systems that need to perform in real-world conditions.

STRUCTAflor® Colour-Coded System

STRUCTAflor® panels are easily identified by their colour-coded tongues and coated edges. Each colour indicates the thickness of the board and its load capacity, helping builders choose the right option quickly and accurately.

• YELLOWtongue® (19mm): Suitable for residential flooring with joist centres up to 450mm.
• REDtongue® (2 mm): Ideal for larger spans up to 600mm, perfect for residential and light commercial builds.
• BLUEtongue® (25mm): Designed for heavy-duty flooring applications in residential, commercial and industrial environments.

The thicker the board, the greater its load-carrying capacity and stability. Reduced joist spacing also increases the strength of the overall flooring system.

YELLOWtongue® Flooring

YELLOWtongue® is an all-purpose structural flooring option for residential applications. It supports general imposed loads as outlined in AS/NZS 1170.1:2002 and is suitable for both platform and fitted flooring systems.

Each panel is moisture-resistant and treated with a wax coating on the edges and surface for added protection. It’s guaranteed for up to five months of weather exposure and available in multiple sizes, including 1800 x 600 mm, 3600 x 600mm and 3600 x 800mm.

REDtongue® Flooring

REDtongue® is designed for projects requiring higher load capacity or wider joist spacing. At 22mm thick, it supports joist centres up to 600mm, making it suitable for residential and light commercial construction.

Available in 3600 x 800mm and 3600 x 600mm panels, REDtongue® provides flexibility and strength for subfloors in homes and light industrial spaces. It is also available in termite-treated and foil-backed versions for extra protection and performance.

BLUEtongue® Flooring

BLUEtongue® is the heavy-duty option for large-scale residential, commercial and industrial applications. At 25mm thick, it supports greater loads while maintaining structural integrity over wider spans.

When installed over joists at 300mm maximum centres, BLUEtongue® flooring can support live loads exceeding 6.7kN and uniformly distributed loads up to 31.5kPa, making it ideal for gyms, warehouses and other high-load environments.

Choosing the Right STRUCTAflor® Flooring

When selecting the right STRUCTAflor® board, consider:

• Load requirements: Thicker boards for higher loads or wider joist spacing.
• Environment: Termite-treated or radiant barrier options for extra protection.
• Moisture exposure: STRUCTAflor® Ultimate for enhanced moisture resistance and thermal performance.
• BAL rating: STRUCTAflor® Ultimate also meets BAL 29 for bushfire-prone areas.

For damp or humid subfloors, STRUCTAflor® Ultimate is recommended, offering up to 80% less moisture uptake compared to other common wood subfloor products. It also significantly reduces the risk of mould growth during and after construction.

If you are installing timber flooring above your subfloor, STRUCTAflor® Ultimate provides the ideal base: stable, smooth and strong, ensuring a perfect finish every time.

Why Builders Choose STRUCTAflor®?

STRUCTAflor® offers versatility and reliability across the entire range. From residential homes to large-scale commercial builds, each product delivers the same level of quality, compliance and peace of mind.

Proudly Australian-made from sustainably sourced plantation pine, STRUCTAflor® products are built for strength, longevity and environmental responsibility. Whatever the project, STRUCTAflor® has a colour-coded solution ready to perform.

STRUCTAflor®. Trusted by builders. Designed for Australian conditions.