What is Yellow Tongue Flooring?
Yellow tougue flooring refers to a 19 mm-thick structural particleboard sheet, used as a subfloor over joists or bearers. It gets its name from the coloured strip along the edge, which helps builders identify sheet thickness easily during installation. These boards are designed to support general domestic and light commercial builds.
Where It’s Used
This product suits both platform flooring (where sheets are laid before walls go up) and traditional fitted flooring. Sheets have a tongue-and-groove profile, which allows them to interlock neatly and reduces movement between boards.
Typical specs include:
- 3600 x 800 mm sheet size
- 19 mm thickness
- Designed for 450 mm joist centres
- Can be nailed or screwed directly to framing
Moisture and On-Site Durability
Each board has a resin-coated surface and wax added throughout to help resist moisture. The edges are also wax sealed to help reduce moisture uptake at joins. While not waterproof, they hold up well under typical site exposure, especially when stored flat and covered.
Options for Different Conditions
In areas prone to termites, H2-treated variants are available (STRUCTAflor Terminator). These include a safe termite treatment that’s built into the board.
If thermal performance is a priority, R-flor® boards come with a reflective backing to improve insulation under suspended floors, particularly useful in cooler regions.
Trade Supply and Support
At Greenhill Timbers, we supply yellow tongue flooring across Melbourne and beyond. If you’re not sure which variant suits your project, or you need help with quantities, we can assist. We stock standard yellow tongue along with H2 and R-flor® options, all available for delivery.










03 9465 9875



