Yellow Tongue Particleboard Flooring

No. Yellow tongue is moisture-resistant, not waterproof. It is bonded with a moisture-resistant resin and the surface and edges are coated to handle weather during construction. In bathrooms, laundries and toilets it can be used beneath an impervious floor surface, but the floor must be fully waterproofed to AS 3740. It should not be left permanently wet or used as a finished wet-area surface on its own.

Yellow tongue is 19mm. The tongue colour signals the thickness. In the Laminex General Purpose range that Big River supplies, 19mm has a green tongue, 22mm a beige tongue and 25mm a brown tongue. Choose the thickness to match your joist spacing and load – 19mm suits joists at up to 450mm centres, which covers most domestic floors.

Use 19mm for standard domestic floors with joists at up to 450mm centres. Step up to 22mm if your joists are spaced wider (up to 600mm centres) or the floor carries heavier loads. The choice is driven by joist spacing and load, not preference, so check the span capacity for your framing before ordering.

Use a construction-grade adhesive made for particleboard flooring, run as a bead along every joist and along the tongue-and-groove joints. Gluing as well as fixing gives a stiffer, quieter floor. Fix the sheet down before the adhesive skins over and clean off any squeeze-out. Installation follows AS 1860.2.

Yes, beneath an impervious surface, provided the floor is waterproofed to AS 3740. The particleboard is the structural base, not the waterproof layer. Wet rooms should be fully waterproofed.

The tongue colour codes the thickness and span rating. In the Laminex General Purpose range Big River supplies, green is 19mm for standard domestic floors, beige is 22mm for wider joist spacing or higher loads, and brown is 25mm for heavy-duty, commercial and industrial floors. All three are the same General Purpose structural particleboard, rated for different spans. Colour coding varies by brand – the 19mm sheet is widely known generically as yellow tongue.

They are usually the same thing described two ways. Yellow tongue is the generic builder term for 19mm structural particleboard flooring; green is the actual tongue colour Laminex uses on its 19mm General Purpose sheet, which is what Big River supplies. Different brands use different tongue colours. In any wet area, particleboard flooring must sit beneath a waterproof membrane installed to AS 3740.