Tongue & Groove, Australia’s leading producer of solid-engineered oak flooring, honours and classifies the inherent beauty of European oak through a unique grading system.

Every piece of timber Tongue & Groove engineers carries a unique story narrated through its knots, grain, sapwood and heartwood – all natural characteristics of oak. Grading is used to categorise the prevalence of these natural features, giving designers the creative freedom to enrich fitouts with a specific aesthetic. Their briefs could call for a clean finish that showcases the refined grain of natural European oak, or a richly textured surface replete with individual character. 

The Tongue & Groove grading system

Tongue & Groove sources timber from plantations throughout Europe that practise sustainable forestry and are recognised by the Forest Stewardship Certification (FSC). This provenance – alongside each tree’s age, height, and health when harvested – gives every piece of timber a unique character.

It’s important to note that features such as knots, grain and medullary rays are not impurities or imperfections. They are beautiful aesthetic features that are testament to the life and journey of the tree from which the timber is sourced.  

In keeping with this, grade is not a reflection of quality, stability, structure or longevity but rather a way to categorise the abundance of these organic features. The grading of engineered timber flooring is not governed and each supplier establishes their own unique system based on different levels of natural expression. 

Tongue & Groove organises its boards into three grades: Natural, Classic and Prime. Each category offers a higher standard than equivalent grades on the market.

Natural Grade 

Natural Grade celebrates the organic essence of European oak, with a richly textured grain and ample knots. These boards are the same quality as Tongue & Groove Classic and Prime Grades, but are derived from the majority of the tree, making them more widely available. 

Tongue & Groove Natural Grade aligns aesthetically with the industry’s Classic Grade equivalent. 

Classic Grade 

Classic Grade are the most widely used Tongue & Groove boards. This versatile finish features fewer knots than our Natural Grade yet retains the naturally dynamic grain and character of European oak. This grade of timber brings a natural elegance and tactile yet refined quality to interiors. 

Prime Grade 

Prime Grade features a refined finish with minimal knots, showcasing the natural grain of European oak and bringing a clean and minimalist look well-suited to contemporary interiors. This elegant timber is considered premium as it can be sourced from just five percent of the tree, making it a scarce and precious resource.

Raising the industry standard 

The ability to specify Grade, Finish, Colour, and Format of Tongue & Groove engineered European Oak boards gives Australia’s architecture and design community unprecedented choice and the ability to create consistently beautiful interiors. The clear definition between each grade in the Tongue & Groove grading system allows designers to make informed decisions about specification and achieve a consistent finish.  

Read more about Tongue & Groove grading on the website.