Oak Wood

The Legacy of Oak Wood in Britain

Oak is a timber species deeply rooted in British culture. Known for its history, strength, and longevity, Oak wood has long symbolised durability and tradition. Many of us see our own values reflected in its character – steadfast, reliable, and resilient.

At Cocking Sawmills, this connection is more than symbolic. English Oak wood (Quercus robur) is central to our operations. For over 30 years, we’ve milled Oak timber for joiners, framers, foresters, and furniture makers who share our deep appreciation for this remarkable hardwood.

Oak is so familiar that we often overlook its unique properties and potential. Let’s take a closer look at this extraordinary wood.

What Is Oak Wood?

Oak belongs to the Quercus genus. In Britain, our woodlands are home to Quercus robur (pedunculate Oak) and Quercus petraea (sessile Oak). Together, they’re commonly referred to as European Oak, a term that also includes French and Eastern European varieties.

Though these Oaks share a name, their timber characteristics can vary significantly. Understanding the different types of oak wood is essential when selecting material for specific projects. That’s why we document the specific origin and provenance of our British Oak, including the exact woodland it came from.

Oak Wood: Characteristics & Appearance

Oak trees are deciduous and widely distributed across Britain and Europe. Most Oak timber is sustainably sourced from well-managed woodlands. The heartwood is pale yellow-brown with a medium to coarse grain. It tends to be straight but can vary with different cutting methods.

Oak is workable by both machine and hand tools, although the grain pattern may affect ease of use. Its natural moisture and acidity make it hard to treat, but it takes glue, stain, and polish exceptionally well. As a hardwood, Oak is strong, durable, and exhibits moderate moisture movement.

Oak Wood: Technical Info from TRADA

Wood Type: Hardwood

Mechanical Strength: High

Durability: Durable

Treatability: Extremely difficult

Moisture Movement: Medium

Texture: Medium to coarse

Density (12% moisture): 720 kg/m³ (±20%)

Oak Timber: A Closer Look

Oak is best known for its golden, yellow-brown hue. Colour varies depending on origin and grade. The contrast between the creamy sapwood and darker heartwood adds visual interest to projects.

Quarter sawn Oak reveals medullary rays – a shimmering flame pattern highly prized by woodworkers. Oak grain may be tight and straight or broad and wild, influenced by the tree’s age, soil, and climate.

Size and Dimensions

Oak trees can grow up to 30 metres tall with trunks reaching 1.5 metres in diameter. These dimensions make Oak wood ideal for structural uses like beams and mantelpieces.

British Oaks often have shorter boles than their European cousins. However, estate-grown trees in the UK can produce very wide sections due to uninterrupted growth. In contrast, managed European forests yield long, straight logs – perfect for wide boards.

Thanks to modern investment in drying and handling, we can now stock longer and wider boards than ever before.

Oak Timber Stock

We hold Oak stock across all product areas. Every week, we produce fresh sawn beams and Oak cladding. Logs are milled into boules, which are then air dried and turned into waney edge boards.

We also carry square edge boards from France, Croatia, Serbia, and other certified suppliers. These are available in Character, Prime, and Super Prime grades, with feature grades like Pippy and Burr Oak regularly added.

Available Thicknesses

18, 20, 27, 34, 41, 54, 65, 80, 100, and 120mm
Square edge boards go up to 150mm.

Typical Widths

300–500mm (occasional boards exceed 1 metre)

Lengths

Start at 2.0m and can exceed 8.0m – though longer boards are rare, they are increasingly popular.

Download our Oak wood pdf which gives a good overview of the Oak wood types we stock

Where Oak is Used

Oak wood is suitable for a wide range of projects thanks to its strength, durability, and beauty. Green Oak framers, joiners, furniture makers, carvers, turners, garden designers, and landscapers all use it.

Homegrown Oak offers exceptional strength and weather resistance due to its tannins and density. It weathers gracefully outdoors, developing a silvery patina over time.

We stock Oak in all forms: round, sawn, planed, air-dried, kiln-dried, or profiled. From English and French to Eastern European Oak, you’ll find everything from pippy and burr to quarter sawn and crown cut.

Bonus: Oak is non-toxic, so it’s safe for children’s play areas.

Considering Alternatives

If you’re exploring alternatives, American Oaks (Quercus rubra and Quercus alba) are often used in joinery and furniture making. We don’t stock them but can advise where to find them. Environmentally speaking, we prefer suggesting closer options with a lower carbon footprint.

For tough internal timber, Beech or Sweet Chestnut are good substitutes. For structural uses, consider Sweet Chestnut or Douglas Fir. In terms of visual contrast, Ash offers a light, cool tone, while Walnut provides a deep, rich warmth.

Exploring Alternatives

Looking beyond Oak? Here are some options:

• American Oak (Quercus rubra, Quercus alba): Often used for joinery and furniture. We don’t stock these but can point you in the right direction.
• Beech or Sweet Chestnut: Great for tough internal timber.
• Douglas Fir: A solid alternative for structural uses.
• Ash: Offers a light, cool tone.
• Walnut: Deep, rich warmth for contrast.

Understanding Tannins in Oak

Tannic acid (or quercetinic acid) is a natural compound in Oak that adds to its durability. However, it can leach when exposed to moisture, leading to brown stains – similar to tea marks.

This is common with fresh sawn Oak and external projects. If you’re working on an outdoor build, it’s worth discussing tannin staining with us first.

See our blog on tannin for more details.

Oak Grading Explained

We use three main grades to meet project needs:

• Character Oak

• Prime Oak

• Super Prime Oak

Let’s explore each one.

Character Oak

Technically, as documented by Making the Grade, this refers to a relatively low grade of timber that exhibits a mix of inter-grown knots, pin knots, heart shake, or colour variations.

We use the term Character Oak to describe a very broad grade that includes anything that falls below Prime, 1st grade Oak standards with exceptions only for our feature grades. It represents one of the most expressive types of oak wood we stock.

This then means under the term Character, our boards include 2nd Grade Oak and incorporated subgrades plus may include pin knots, splits, cracks, heart shake, insect attack, bark pockets, areas of rot, sapwood and colour variation.

As an overview, we don’t put restrictions on boards in this grade, provided the appearance and mechanical properties of the particular timber are suitable for its intended purpose. In this way, our character grade should not be confused with sub grade, rustic timber which may well be technically usable but doesn’t meet general serviceability requirements and isn’t able to be graded.

Our actual stock then incorporates particular selections within the grade of Character Oak.

Waney Edge Character Oak stock will generally sit in original boules and we select and measure from the stack depending on each customer’s requirements, preferences and the particular use for the board.

Square Edge Character Oak stock is a different thing altogether. Here a more sophisticated, applied grade selection has been carried out, and boards are stocked in packs of similar grade qualities.

These packs tend to contain the higher qualities of Character Oak wood, the 2nd grades which exclude more rustic features and, in terms of appearance, are more representative of real Oak with good grain patterns, sound knots, lovely honey colouring… everything one normally expects from real Oak.

This means by selecting from packs it’s possible to get a consistent grade and overall ‘look’. This speeds up selection and is useful for flooring projects, cladding projects, bespoke kitchens, door manufacture and furniture range manufacture, where all boards need to have similar colouring, knot sizing and grain pattern. By selecting from graded packs of Square Edge Oak you get reassuring consistency, even in Character grades.

Prime Oak

The term Prime has always been used to indicate the top grade of timber.

Its criteria is used to verify the mechanical properties of a board by visual means and seeks to differentiate Prime graded boards as boards that are fit for specific purpose, namely joinery, cladding, cabinetry, furniture making or highly machined timber products.

In this way, the grading of Prime timber is about what is allowed within a board outside of straight grain, even colouring and good quality wood husbandry.

In Prime Oak, we allow one intergrown knot* up to 20mm diameter or several small knots up to a 20mm combined diameter**. One small bark pocket is allowed. Small sap bands are allowed – we follow the French convention of ‘one in, one out’, the underlying principle being to provide a ‘fair measure’.

In selecting from Prime Waney Edge Oak boards to a cutting list or customer requirement, we would measure out the waney edges (re:sap), the heart cracks, large knots, shakes and other typical board features that are not allowed within the grade so the board measure (the bit you pay for) would only include what comes within Prime grade, although you may receive a whole waney edge board.

Prime Oak wood colouring is relatively even, but for particular consistency of colour, the best method of selection is to choose boards absolutely from the same origin and ideally from the same boule – particularly important when working with English oak timber.

In this way, Prime timber does waste more wood than other grades but it is how a single, unique waney edge board can be used to select for a multitude of grades and purposes which is one reason we love our waney edge timber.

Our Square Edge Prime Oak timber has been pre-selected into grades at the milling stage and is an easy, reliable, fast way to buy Oak wood, especially if you are self-selecting. These boards can be just taken straight from a timber stack and each board measure meets the stated grade on at least one face, if not both.

For homegrown waney edge Oak wood take a look at Making the Grade – Oak grade 1 for illustrations of Prime Oak

Super Prime Oak

Super Prime is a term that indicates a grade ‘above’ Prime.

It’s a grade that has been normalised as a timber grade in the UK for high-grade imported square edge Oak. It’s a description we use of a grade that goes above and beyond normal Prime Oak timber qualities and requirements.

Super Prime is a selection of the most pristine, the most clear, the most pale and evenly honey coloured, usually Eastern European, Prime Oak wood you will ever see. In most mills, it’s edged after kilning in a re-grading process. More labour intensive but definitely serves to refine the grade. I think we’ve called it ‘relentlessly clean’ before and that about sums it up.

Knots aren’t strictly excluded but if you see one it’ll be a small pin knot and only visible on one face. The other face will undoubtedly be clear. The same applies to sap. In Super Prime Oak there will not be a lot of grain pattern. There will not be a lot of variation of anything. There will be no dark colouring, No bark pockets, No wild grain, No splits, no cracks, no shakes. There may be a high proportion of Quarter Sawn boards. There may be a lot of very flat boards. There may be a lot of very straight boards.

If you have a large run of Oak doors and you need them all to look and behave the same, use Super Prime. If you need a quiet, understated solid wood for an interior surface use Super Prime. If you need simple elegance with embodied strength and durability for a feature staircase use Super Prime.

Feature Grades in Oak

Tiger or Brown Oak

Burr Oak

Quarter Sawn Oak

Oak Origin and Provenance

Oak species grow around the world, but Quercus robur (common or pedunculate Oak) is most common in Britain and Western Europe. Provenance affects timber properties, with soil, light, and weather influencing each log.

English Oak

Britain’s most iconic tree – strong, hard-grained, and full of character. Once used in Royal Navy ships, English oak wood remains a symbol of national pride.

English Oak is characterised as one of the strongest Oak wood species, with more interlocking grain than other European Oaks, creating a fine, hard surface. It can be difficult to work, but often also has a great deal of character. The term “English Oak” can refer to oak grown in England or the species Quercus robur, so be careful of the meaning when people refer to “English Oak”. They could mean Quercus robur that is not necessarily grown in England.

French Oak

Revered since Druidic times. High tannin content helps it absorb and retain stains beautifully.

Eastern European Oak

Particularly from Croatia’s Slavonia region. Known for stability and even colouring. A national symbol of Croatia.

How Will You Use Your Oak?

Whether you’re building, crafting, restoring, or designing, Oak offers reliability, beauty, and a story that spans centuries. Choosing the right type of oak wood ensures the best outcome for your project.