Welcome to part 2 of our series on wood types. This week I’ll be discussing oak & oak wood treatments. If you haven’t already read part 1, feel free to go check it out here: All about Pine Wood.
A Little History of Oak
Oak (or quercus as it is known in Latin) is a hardwood with some 400 known species. It has always been a popular wood in the UK, but in recent times it is even more widely used in construction and also as internal fixtures in clubs and gyms etc. For furniture construction, oak has become ever more the wood of choice, a trend expanding year on year since the year 2000 when China, India and Indonesia substantially increased their export markets. Pine has been the wood to suffer from oak’s popularity as it is more widely available in the Far East.
The flowers of many oak trees are known as catkins and they are produced by oaks when they reach their reproductive age, which is typically around 20 years. They are triggered by rising temperatures in spring. Ultimately it is the catkins of many oaks that turn into the acorns, so maybe that popular phrase… ‘mighty oaks from little acorns grow’ should be ‘mighty oaks from little catkins grow’, although it doesn’t quite have the same ring, does it?
Acorn of the mighty oak tree.
Treating Oak Wood
With regard to finishing and treating oak, there are numerous possibilities, but there are certain requirements that are asked for time and again… Often we are asked how external oak can be kept looking natural. Whilst the question is easy, the answer is not so straightforward. These are the necessary considerations:
- When water penetrates oak, it reacts with the high tannin content within oak, resulting in ‘blackening’.
- The sun’s UV rays will turn the oak to a silvery hue over time.
- Clear products are inevitably not completely clear, so they tend to ‘bring out’ the natural colours of the oak, normally making it a bit darker and warmer.
- The levels of rain, wind and sun will make a difference to how quickly the oak changes colour.
Oak turned grey/silver by UV rays & water damage.
Oak barrels traditionally used for whisky and beer.
If the requirement is to keep the oak looking as natural as possible, whilst preventing blackening or silvering as much as possible, then the following is the best system we know of:
- 1 coat of clear wood preservative
- Followed by 2 coats of Osmo UV Protection Oil 420 Extra
Osmo 420 Extra offers UV resistance and also contains biocide which is important for external timbers as it prevents the wood from becoming diseased with wet rot, dry rot and blue stone etc. The oil also repels water, thus preventing it from going black.
If the requirement is to protect the oak whilst keeping the silvery appearance, then the following is the best:
- 1 coat of clear wood preservative
- Followed by 3–5 coats of high-quality tung oil such as Morrells Tung Oil
Tung oil is one of the clearest oils on the market and doesn’t offer UV resistance.
If the exterior oak needs to be coloured, then the following system is recommended:
- 1 coat of clear wood preservative
- Followed by 1 coat of your chosen colour of Osmo Natural Oil Woodstain
- Followed by 1 coat of clear Osmo UV Protection Oil 420 Extra
If blackening on exterior oak needs removing, then scrubbing with a fungicidal wash such as Barrettine Mould and Mildew Cleaner is recommended. On the other hand, it may be the silvering that needs removing. If so, a scrub with Osmo Wood Reviver Gel (which contains oxalic acid, amongst other active ingredients) is recommended.
Unfinished oak.
Treated oak.
One of the most common enquiries we get is how to keep internal oak looking natural. This is not just a case of simply applying ‘clear products’ as they bring out the natural colours of the wood, thus making it a little darker and more golden. A very good indication of how your oak will look once it has been finished with a ‘clear’ coat is to dampen an area by applying some water with a clean cloth or sponge. The look achieved when the wood is damp/wet is very close to how it will look once a clear varnish or a clear oil has been applied.
Some customers like the way oak colours when clear coatings are applied to it, whilst others want it to be as close as possible to how it looks in its natural state. A more natural look can be achieved by using wood oils that have been specifically formulated to retain the natural appearance of interior oak. These products include:
- If an oiled finish is preferred, then apply two thin coats of Fiddes Hard Wax Oil Natural or Osmo Polyx Oil Raw.
- If a varnished finish is preferred, then 1 part Manns Classic Wood Dye can be mixed with 50 parts Manns Extra Tough Interior Varnish.
Clear wax polish is the one exception to the above… If a clear wax polish is applied to bare oak (or just about any other wood for that matter), then the colour is kept very natural indeed. It’s just a question of whether a wax polish is going to be durable enough. Internal doors, for example, are considered, by most people, to be ideal for finishing with wax, whereas a floor will look nice once waxed but regular maintenance is required, so most people don’t opt for wax for this reason.
If the oak needs to be made darker, then Osmo Polyx Oil Tints or Fiddes Hard Wax Oil Tints are ideal because they colour and protect the wood in the same application. It is always good to try and finish with a clear coat if possible because if the wood gets scratched, it is the clear coat that scratches before the coloured coat and therefore the scratch is not as noticeable.
Oiling Consideration
If oak is being oiled, it is a good idea to sand it with sandpaper that is no finer than 150 grit. The reason for this is that the pores of the wood are more open, thus allowing the oil to sink into the wood better. Better absorption equals greater protection.
Interesting Oak Stats
- Oak bark is rich in tannin and is used by tanners for tanning leather.
- Acorns can be used for making flour or they can be roasted for making acorn coffee.
- Tannin dissolves and escapes from the wood. Wine barrels are made from oak and it is the tannin that helps to give the wine its colour.
- Sessile oaks of Europe can reach heights of up to 40 metres.
- Oak trees regularly live to be 500 years old, although 1,000-year-old oaks are also known.
- A mature oak tree can produce up to 50,000 acorns!
Need help finishing a project made with oak?
For more help and advice on how best to finish oak, contact our team of resident experts who are always on hand to help with project advice and product recommendations.
We love to see before, during and after photos of any wood finishing project. If you would like to share your project pictures with us and our followers, you can either send us some photos or share on our Facebook, Twitter, Pinterest or Instagram pages.
469 comments
You mention Osmo and Fiddes for an oil finish for internal use, but looking into these they are both high in VOCs and as such not something I’d want to use internally. Do you have any low or no VOC alternatives? I know Osmo do their 2K but that only comes in matt and I’m currently looking for satin.
Reply to Andrew:
Hi Andrew, All of the Osmo & Fiddes products have high VOC content as they are solvent based. Please consider the Polyvine Wood Oil which is ultra low VOC
https://www.wood-finishes-direct.com/products/polyvine-wood-oil
hope that helps – Alison.
Hello, I have no idea whether this thread is still live but this post has been THE most helpful thing on the internet!
We have just bought a new dining set. I would usually view anything like this in person but have bought end of line/ second hand (online) with the purpose of working on them. I went for solid oak to give myself the best start…however I’m getting intimidated by the overall glossy, orange look. The spindle back chairs are more varied and orange/peachy than the table. Almost like beech wood in places.
We generally prefer things to look more natural and worn in. Is there anything I can do to help this along?! Perhaps starting by sanding off the clear finish and seeing the more natural colour of the wood? I now fear I’ve bitten off more than I can chew! Any advice would be greatly received. Thank you :-)
Reply to Vic:
Hi Vic – Thanks for your message – Any clear product always enriches the natural colours in the grain and Oak can sometimes appear a bit orange/yellow. Using a product that contains a tiny amount of white pigment counteracts this darkening effect. Please consider this penetrative oil which will have a much more natural finish than any varnish/lacquer. https://www.wood-finishes-direct.com/products/osmo-polyx-oil-raw-3044 I would recommend ordering a sample.
You will have to sand the Oak back to bare wood to use this product. – Please come back to me if required – Alison
Hello, thank you for the article.
I have purchased some European oak to use as shelves in an alcove as well as niches in the bathroom. The niches are in the shower/bath and will hold products such as shampoo and soap. They are not under the water stream per say but will get water almost everyday, especially with the wet product bottles being put back there. I am trying to find a finish that will not make the wood look too yellow. I have looked into your osmo polix oil but fear this may not be resistant enough for use inside the shower. If i can’t get as clear and matt a finish as possible i think i may prefer one that if darker does not bring out the yellow and dark veins of the wood too much. Crucially, i really want to avoid water rings and stains. That said if the best solution requires a yearly upkeep i can envisage doing that as as long as it is fairly easy. What would you recommend?
Reply to charlotte_paris@hotmail.com:
Hi Charlotte,
We’d suggest you apply Osmo Wood Protector (4006) first and then follow it up with Osmo Polyx Oil (3062), although you’ll need to keep on top of maintenance with this, otherwise water rings are inevitable unfortunately.
If you’d like to give us a call on 01303 213838, we’d be more than happy to give you further detail and advice around this.
Kind regards,
Samuel
Hi there,
I have just purchased 4 untreated oak spindle chairs. But I am not sure how to go about up-cycling (I.e. would they need to be sanded and oiled/ waxed). Please help!
Thanks!
Reply to Cach:
Good Afternoon,
Can you get in touch via our contact us (https://www.wood-finishes-direct.com/pages/contact) page, with details of the look you would like to achieve, clear or coloured? Transparent or opaque? And maybe some photos, and I can narrow down some options for you to consider.
I look forward to hearing from you.
Kind regards Samantha.
Hi There, I’m hoping you can help me…
…I’d like to re-condition an oak kitchen table, which is mostly solid oak but has some oak veneered MDF panelling in the centre. It has marks (biro scribbles, some etches) in the table top which I know I need to gently sand (emphasis on gently as it’s partly veneer!!), but I am not sure what varnish / oil I need to use to finish and re-waterproof it. It’s a warm oak at the moment and I don’t want to re-colour it, just give it a new lease of life.
Any tips on sanding also welcome!
Thanks, Anne
Reply to Anne Churchfield:
Hello Anne,
So yes, some gentle sanding is the best option, if you try with a 100 grit first to see if that works, if you are looking to remove current finish however you may need to go down to an 80 grit. It is always best to remove previous finishes before applying new ones. This helps to ensure an even all over result, the key to a great finish is always in good preparation. You are right to be cautious for the veneered areas, gentle sanding to avoid going through to the base wood.
Once you have sanded to remove the current finish and any marks, you can sand at a 100 grit and if filler is required this is the time to apply it. Then sand for the final time at a 150 – 180 grit sandpaper, always in the direction of the grain of the wood. I would also recommend a good wipe down with Methylated Spirits to clean and remove and resins or grease on the wood. Doing this can also highlight any flaws in the wood that may require further sanding before you apply a product.
Once you are ready to apply you could take a look at a varnish for durability the Manns Extra Tough Interior Varnish (https://www.wood-finishes-direct.com/products/manns-extra-tough-interior-varnish) is a great option, two coats of this will give a well protected and easy to clean surface. It will darken very slightly and sample sizes are available, which I would recommend for test areas first and to decide which sheen level you might want to consider.
If you would like a more natural appearance to the wood you could also look at a Hard Wax Oil, this soaks into the wood and become part of it. Drying to a hard finish that offers great protection, its not quite as durable as a varnish, however has the benefit of being easier to maintain over time. It is again available in sample sizes and will darken the wood slightly more than a varnish will, because it penetrates the surface of the wood. Fiddes Hard Wax Oil (https://www.wood-finishes-direct.com/products/fiddes-hard-wax-oil) is suitable for most wood types. And it well worth checking out our You Tube Channel >>> https://www.youtube.com/c/WoodFinishesDirect-Folkestone as this has lots of helpful videos with hints and tips for preparation and application methods.
For more help and advice please do not hesitate to get in touch via our contact us (https://www.wood-finishes-direct.com/pages/contact) page.
Kind Regards Samantha.