About oak

Oak grows naturally throughout Europe. Frøslev uses oak of German origin where the trees are up to 2-300 years old when cut down, and only the best of the stemwood is used. We only use certified oak.

Historically, oak was used for things like timber-framed houses, fence posts dug into the ground and for shipbuilding.


Oak has a nice, golden brown shade and is characterised by being a hard wood type and a durable material. The closed cell structure of the oak also prevents water from entering the cavities of the tree and thus also helps to protect the oak tree.

The biggest challenge with oak is dead/rotten knots that occur due to dead branches that remain on the trunk for a long time.

Tiller is also relatively common in oak and causes a decrease in value as irregularities are often not tolerated, especially not in the furniture industry, but also for e.g. façade cladding.

We mainly use oak for planks - long planks for tabletops and short lengths for shelves etc. Both are perfect for do-it-yourself projects. The planks are solid and rustic with a dressed bark edge.

Alternatively, oak can be used for structural timber and as posts where pressure-impregnated wood may not be used. Oak is also a good alternative to exotic woods.

The oak sapwood can be relatively easily impregnated whereas the heartwood is extremely difficult to impregnate. As the sapwood is most often cut off during production, oak is in practice not impregnated.

Sapwood, for example posts dug into the ground, will have a practical and expected durability of 15-20 years.

Processing and protection

Oak is naturally protected against rot and fungi and therefore does not require further treatment. The wood contains tannins, and the tannic acid has a corrosive effect on iron. Corrosion-proof nails and screws should therefore be used.

If oak is used for external cladding, a basic treatment with fungicides and a top treatment with a pigmented façade oil or the like is recommended.

To the greatest extent possible, all wood must be protected by 'structural protection' which means that you plan and build in such a way that the wood is ventilated and water is drained off so that the tree can dry out.

Wood is a natural material and will eventually turn grey. It is a good idea to protect the wood with suitable wood preservatives when dry - either with flat paint finish or transparent wood preservatives.