Yellow Tongue Flooring Sizes And What The Other Colours Mean

As soon as you start researching what type of structural particleboard flooring you need for a flooring project, the first thing that stands out is the multiple colors the pvc tongue insert comes in, quickly followed by the question – ‘what colour means what?’ So what is the difference between the different colours such as Yellow, Green, Orange and the rest?

Quick Takeaway

  • Yellow Tongue flooring is a versatile material with many different uses.
  • Yellow Tongue flooring is designed for subfloors, but can also be used for suspended multi-stories as well.
  • There are different types of Yellow Tongue flooring for different weight requirements.
  • Yellow Tongue flooring is moisture-resistant and can withstand being outside for up to three months.
  • Yellow Tongue flooring is heavy and has sharp edges, so handling with care is important.
  • If you’re interested in what other DIY projects you can use structural flooring for, check out this article.

Yellow Tongue, Red Tongue, And The Rest Of The Particleboard Flooring Colours

The various coloured tongue flooring is structural grade particleboard commonly used for subfloors in Australia and NZ, where the coloured PVC strip is used as the tongue component of a tongue and groove (t&g) arrangement. In this blog post, we will discuss what to look out for when trying to tell them apart from one another so that you can make an educated decision with ease based on various material qualities and settings. We also go over the performance requirments for the installation of structral particleboard and AU/NZ specifications for particleboard flooring which are acceptable.

Yellow Colour Tongue Particleboard Flooring: What It Means

Getting straight to the point if you’re in a hurry and haven’t got time to drill into the mysterious depths of coloured tongue structural flooring in Aus and NZ, here is the short answer:

  • It is a 19mm thick structural grade particleboard manufactured by Australian Panel Products (formerly Borg Manufacturing) under the brand STRUCTAFlor.
  • It is intended for interior use in domestic construction and is particularly suited to platform construction, primarily used for subfloors with a joist spacing of no more than 450mm prior to the erection of walls.
  • In terms of sizes, it is available in widths of 3600×800 and 3600x600mm.
  • In regard to waterproof status, it is designed to withstand a short period (a few months) of intermittent rain exposure during the construction process, so it is more a case of resistance.
  • Weight is approximately 30kg per sheet.

As far as an alternative to this STRUCTAFlor option, there are similar 19mm thick structural grade particleboard alternatives manufactured by D & R Henderson (orange tongue), and Laminex (green tongue – see next section). Also, see Table 1 below for more details and specifications.

Keep on reading if you want to find out how its specifications fit in with all the other colours and brands of structural grade particleboard sheet flooring.

What Is Green Tongue Flooring?

Green tongue flooring is one of the popular alternatives to the yellow option:

  • Green tongue flooring is a 19 mm thick structural grade particleboard product manufactured by Laminex in Australia.
  • It is intended for interior use in domestic buildings, primarily used for subfloors with a joist spacing of no more than 450mm.
  • It is available in widths of 3600×900.
  • While it is manufactured to comply with the same AS/NZS 1860.1:2017 specification as the yellow option, it is generally considered by the industry to have better long term moisture-resistant properties, so is often used in situations where there is higher humidity and a likelihood of increased moisture exposure.
  • It is also a termite-treated version available.

There are similar 19 mil thick structural grade particleboard products manufactured by D & R Henderson (orange tongue), and Australian Panel Products (STRUCTAFlor Yellow). See Table 1 below for more details.

What Is Red Tongue Flooring?

Again, the short answer for red tongue flooring:

Red tongue flooring is a 22mm thick particleboard sheet flooring for use in domestic and residential construction. The product is manufactured by Australian Panel Products (formerly Borg Manufacturing) under the brand STRUCTAFlor. It is intended for interior use in domestic construction, primarily used for subfloors with a joist spacing of no more than 600mm. It is available in widths of 3600×800 and 3600x600mm. It is also available as a termite-treated version called TERMIFlor and as a foil backed termite treated version called R-Flor.T

There are similar 22mm thick structural grade particleboard products manufactured by D & R Henderson (burgundy tongue), and Laminex (beige tongue). See Table 1 below for more details.

Country Differences

T&G chipboard for subflooring does exist in the UK, but is not commonly available with the coloured PVC tongue – instead, the tongue is a milled down section of the chipboard.

OSB or plywood is typically used in the United States for structural flooring, so the whole coloured PVC tongue structural particle subflooring thing is pretty much an Aus / NZ thing.

Confusion On What The Coloured Tongues Represent

To say there is some confusion about what the different coloured PVC strips indicate is an understatement. The reason for this confusion is that there is no overall standard for the various colors of the tongues across the three main Australian companies that manufacture them. If you do research online about the issue, you will find numerous definitive statements about that state of things in woodworking forums, etc, but when you drill down into the daisies, it turns out that the answer you think you found is not definitive, and doesn’t completely make the issue clear.

Different System For Each Company Based On Thickness

The only way through this is to understand that the three different manufacturers use various colour tongues to differentiate their own range of structural particleboard, but the ‘system’ one company use is not the same system as a competitor does.

The trick is to look at what the different colour tongues mean per manufacturer and why and how they are differentiating their particleboard offering with tongue color. Although each manufacturer uses a different tongue colour system, they assign a single colour to one of the three different particleboard thick profiles commonly available (19 mm, 22mm, 25mm). In some cases, they will use a coloured wax edge strip on the board to indicate other treatments – mostly associated with termite resistance.

Joist Spacings Based On Particleboard Thickness

The difference in thickness changes the allowable joist spacing. So a 19ml particleboard can have a maximum floor joist spacing of 450mm, while a 22mm thick board can have a 600mm joist spacing.

Australia / New Zealand Structural Particleboard Standard

Table 1: Structural Grade Particleboard Sheeting In Australia

The standard that governs the manufacture of particleboard flooring is AS/NZS 1860.1:2017 and sets out the minimum performance requirement. It specifies two classes. Class 1 flooring is for use in Australia where during construction, prolonged exposure to an ambient temperature above 25°C under moist conditions can occur. Class 2 is not suitable for Australian conditions.

What Are The Similarities Across All Colours?

All t&g structural particleboard have some basics in common, all based around the AS/NZS 1860.1:2017 standard.

It is all manufactured from particleboard. The t&g feature allows boards to be laid flat without gaps or overlapping. The grooves on one board align with the tongues from an adjacent board, forming perfect seals when nailed together. For any of the water-resistant versions, this feature goes a long way to maintaining a water-tight seal when laying a subfloor. This tongue-and-groove approach interlocks at every joint to create a seamless surface that’s perfect for high-traffic and high moisture areas such as kitchens or bathrooms.

Moisture Resistance Qualities Of Structural-Grade Particleboard Sheeting

Structural-grade particleboard sheeting can be exposed to the elements for up to three months, but it’s always a good idea to enclose a building as soon as you finish installing it. You should get rid of any ponded water as soon as possible. If there’s ponding on the floor, you can get rid of it by drilling holes 3mm maximum diameter at least 1 meter apart and sweeping water away.

Keep packs off the ground when storing them outside. Cover the product with waterproof sheeting so that air can circulate freely.

So while the material will tolerate some weather, it should be covered as soon as possible. If you peer through the fence at a residential building site while taking a weekend walk through the suburbs, you will often see it laid as subflooring before the roof is on, but sure enough, not long after, the roof will be on, protecting the subflooring for anything more than the odd passing shower during the building process.

Where To Buy Structural-Grade Particleboard Sheeting

Onsite Timber in Sydney Sheets supply sheets of 3600 x 800 x 19mm. They originally sold it at a width of 900mm but changed to 800mm in late 2019. They also sell two other different coloured tongue products that are the same size but have different thicknesses. Blue Tongue has a thickness of 25mm, Red Tongue is 22mm along with their Yellow option is 19mm. So this is a case of different colours being used to denote different thicknesses.

Bunnings and others sell STRUCTAflor, manufactured by Borg Manufacturing. STRUCTAflor uses the same coloured tongue system as what Onsite Timber sells, where the different colours represent different thicknesses of the same product. However, STRUCTAflor uses another coloured coding system based on wax applied on the edges of the product to denote other qualities. The edge is coated with coloured wax to indicate other treatments other than thickness. A yellow edge wax represents general purpose use, a light blue wax edge indicates H2 termite treatment and a blue wax edge indicates termite treatment with the addition of a foil backing to improve insulation (this product is marketed as R-Flor).

What Does It Look Like?

The boards have an off-white coloration that becomes yellow when the sheets absorb water or humidity causing them to swell up.

This yellow color is a result of the wood pulp in the sheets reacting with moisture.

💦 Yellow tongue flooring is a substrate that many builders use, but it’s not recommended for external flooring.
💦 Yellow tongue flooring is a treated particle flooring that can absorb water, so precautions need to be taken.
💦 Before waterproofing, ensure that the yellow tongue flooring is screwed and glued to the joist.
💦 Gripset’s express lay sheeting is the number one system for waterproofing yellow tongue flooring.
💦 The express lay sheeting acts as a decoupling sheet system and a waterproof membrane.
💦 If express lay sheeting is unavailable, use the BRW tape or elastic B50 joint band over the joints before applying a liquid membrane.
💦 The GRIPOp or GRI SP is the best primer in the range for yellow tongue flooring.

Green Tongue Flooring

There is no certain differences between Green and Yellow per se, because manufacturers tend to use color differentiation for their own purposes in different countries.

In Australia, green tongue flooring is particleboard made to protect against damp and humid conditions. and the flooring is normally 800mm as opposed to 900mm thick.

In the US, some manufacturers call termite-treated particleboard green tongue flooring, while like Australia, others add degrees of water-resistant treatments to it. In this case, you will hear Green Tongue Flooring it called “aquatech” or “aquatight”. It uses water-resistant glues and is mostly used for wet areas. The pricing of green tongue flooring is more than the yellow, but it’s also used for areas that need to be waterproof.

Differences Between Yellow And Green Tongue Flooring

have tongues that help keep boards together tightly when installed, the green tongue uses water-resistant glue while the yellow does not. This allows them to install as an option on surfaces where water might come into contact with the surface such as pool decks or kitchens with leaking pipes above countertops. The pricing can vary depending on the amount you are installing (more if just doing one area) and what your needs are (green is better at resisting moisture).

The yellow version has a lower price point than its green counterparts which makes them excellent for first-time installers who may need to replace some boards if something comes up during installation; however, this means that water damage is a risk.

Frequently Asked Questions For Coloured Tongue Structural Flooring

What is an alternative to this structaflor flooring?

Any 19mm tongue and groove structural particleboard that meets Aus and NZ standards AS/NZS 1860.1 can be substituted. This includes orange tongue manufactured by D&R Henderson, or green tongue manufactured by Laminex. If a thicker board can be accommodated, then a 22mm thickness red (STRUCTAFlor), burgundy (D&R Henderson) or beige (Laminex) could be used instead.

Is yellow tongue flooring waterproof?

This type of flooring is not waterproof. It is designed to withstand moisture for a few months during the building process but then requires a dry environment once in place for the long term.

Red tongue flooring vs yellow tongue flooring – which is best?

Yellow is 19 millimeters thick and requires a maximum joist spacing width of 450mm. Red is 22mm thick and can be used at joist spacing widths of 600mm. Both are manufactured under the brand of STRUCTAFlor and comply with Australian and New Zealand standards AS/NZS 1860.1.

What are the available flooring sizes?

Yellow tongue flooring is available as 3600 x 800mm and 3600 x 600mm. It was previously available in 3600 x 900mm but is no longer made in that size. If 3600 x 900 mm is required for 19-millimeter structural tongue and groove particleboard flooring, orange tongue (D&R Henderson) or green tongue (Laminex) should be substituted.

Structural flooring: which side up?

It is raw on one side and greasy on the other. Glue is used to attach the raw surface to the floor. The greasy wax side faces upward to protect the surface from moisture.

Can structural particleboard floors get wet?

Although the yellow has a waxy surface on one side to help protect it from moisture, it is made from particleboard. In wet areas, particleboard should not be used for a subfloor. Instead, use FC sheeting. So it can withstand moisture for a short period of time during the initial building process, but it isn’t designed to withstand moisture over the long term.

What is the difference between yellow and orange tongue flooring?

Yellow tongue flooring is a 19 mm thick structural particleboard flooring made by STRUCTAFlor in Australia. It is specified for a maximum joist spacing of 450mm. It is available in 3600mm x 800mm and 3600mm x 600mm.

Orange tongue flooring has the exact same specifications other than it is manufactured in Australia by D&R Henderson and is also available in 3600m x 900mm.

What is Yellow Tongue Flooring?

Yellow Tongue Flooring is a type of particle board flooring that is commonly used in construction where the floor is laid prior to the erection of the walls.

What are the sizes available for Yellow Tongue Flooring?

Yellow Tongue Flooring is available in sizes of 3600 x 800mm.

What does the specification “19mm” refer to in Yellow Tongue Flooring?

The specification “19mm” refers to the thickness of the Yellow Tongue Flooring.

Can Yellow Tongue Flooring be used for general purposes?

Yes, Yellow Tongue Flooring is suitable for general purpose applications.

What are the other colors available in Yellow Tongue Flooring?

Yellow Tongue Flooring is typically available only in yellow color, as the name suggests.

What is the difference between sheet flooring and board flooring in Yellow Tongue Flooring?

In Yellow Tongue Flooring, sheet flooring refers to large sheets of flooring material, while board flooring refers to planks of flooring material.

Is Yellow Tongue Flooring a type of particleboard flooring?

Yes, Yellow Tongue Flooring is a type of particleboard flooring commonly known as Particleboard Flooring Part 1 or Structaflor®.

What are the building supplies needed for laying Yellow Tongue Flooring?

The building supplies needed for laying Yellow Tongue Flooring include adhesive, screws, and underlay.

Is Yellow Tongue Flooring produced to meet any specific standards?

Yes, Yellow Tongue Flooring is produced to meet specific construction standards and requirements.

What is the recommended construction application for Yellow Tongue Flooring?

Yellow Tongue Flooring is recommended for construction where the floor is laid prior to the erection of the walls.

Red Tongue Flooring vs Yellow Tongue: Pros And Cons

Overall, red tongue provides superior stability but comes at a higher price. Yellow tongue is the affordable standard. Professional installation is key to success with either product.

Green Tongue Flooring vs Yellow Tongue Flooring: Pros And Cons

  • Green tongue suits eco-conscious builds, yellow tongue remains the cheaper option
  • Yellow tongue is better for high-traffic areas; green tongue can dent easier
  • Both require seasoned timber and proper acclimatisation before install
  • Prefinished options like laminate flooring avoid refinishing limitations

The choice comes down to eco-friendliness vs cost and hardness. Proper install and protecting from moisture is key for stability of both. Seek advice from flooring suppliers to pick the better option for your specific build.

Is There A Good Alternative To Yellow Tongue Flooring?

Here are some good alternatives to yellow tongue flooring to consider:

  • Plyfloor: Plyfloor is made from layers of hardwood veneer pressed together. It is strong, stable and less prone to swelling or shrinking than yellow tongue. Plyfloor can be sanded and refinished multiple times. The plywood construction provides a smooth subfloor for installing floor coverings.
  • Hardwood flooring: Solid tongue and groove hardwood can be installed directly over joists instead of using a single layer subfloor. This provides a beautiful hardwood floor surface that can be sanded and refinished over time. Popular hardwood choices include spotted gum, blackbutt or tallowwood.
  • Laminate or engineered flooring: These flooring types provide the look of timber with greater stability. Laminate flooring has a hard wearing surface layer while engineered floors have a top layer of quality timber. Both lock together over underlay without requiring a sheet subfloor layer.
  • Concrete: A concrete slab foundation can act as the finished subfloor ready for floor tiles, carpet or other finishes. Concrete provides levelness, stiffness and stability without using sheet flooring. Expansion joints are required to prevent cracking.
  • Ceramic or stone tiles: Tiles offer a durable, water-resistant flooring solution. They can be laid directly onto the concrete slab or screeded floor leveling compound. Tiles avoid the need for a yellow tongue subfloor layer.

The right choice depends on the flooring look you want to achieve, budget considerations and whether an existing subfloor requires replacement. Seeking advice from a builder or flooring company is recommended to ensure you select the best yellow tongue alternative for your project.

What is a good alternative to yellow tongue flooring?

Here are some good alternatives to yellow tongue flooring:

Particleboard Flooring

  • Red tongue flooring is a thicker 22mm particleboard that allows wider joist spacing of 600mm[2]. It has enhanced moisture protection with wax coated edges[2].
  • Blue tongue flooring is similar to red tongue but with added termite and moisture resistance[1].


  • Plywood subflooring provides a smooth and stable surface for floor finishes[3].
  • It is a sturdy material that can span joists spaced up to 600mm apart[4].
  • Marine grade plywood has waterproof glue and is very moisture resistant[5].

Fibre Cement

  • Cement sheet flooring like Hardiflex is termite resistant and fire retardant[4].
  • It can span joists spaced up to 450mm apart[3].
  • Cement sheet tiles are an affordable tile underlay option[4].


  • Plywood and fibre cement are more expensive but provide better moisture resistance than particleboard[3].
  • Particleboard is the most economical option but requires sealing cut edges to prevent moisture damage[5].
  • Red or blue tongue particleboard provides added durability over standard yellow tongue[2].



So which one should you go for? Ultimately, depending on your needs, you can decide which option will work best for you. Yellow has a lower cost point but does not offer as much protection from water damage while green costs more initially but offers excellent resistance to moisture.

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