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
Hi,
Would you please suggest what could be done to protect the table in the future considering we want it as close to natural as possible.we just bought a dining table which is untreated dry oak and already see how quickly it stains from everything.
Also, what could be done to remove already existing water and oil stains?
Thank you so much for your time.
Best Regards,
Nina
Reply to Nina Stepanenko:
Good Afternoon Nina,
Thank you for getting in touch with your enquiry. I can recommend a great product for you to have a look at that will maintain the natural appearance of the wood, Fiddes Hard Wax oil Natural (https://www.wood-finishes-direct.com/products/fiddes-hard-wax-oil-oak-lightening) this contains a minute amount of white pigment to counteract the darkening that you get with a standard clear oil.
This oil penetrates the surface of the wood with just two very thin coats being required for application. Sample sizes are available and I would recommend these as the wood you are applying to will impact on the colour and result that can be achieved. The oil dries hard and gives a protective, moisture repellent finish to the woods surface and it is easy to apply, clean and maintain over time. It will not peel and flake and can simply be topped up when you feel the wood needs it, depending on how much the table, this could be annually, but more likely 2 or 3+ years on.
If you have a read up of the product details and I would recommend visiting our You Tube Channel >>> https://www.youtube.com/channel/UC7-tgwbsUxm73aVnAjLGHRA for videos with helpful hints and tips on preparation and application.
Plus I am here to help if you have any further questions.
Kind Regards Samantha.
I had used hot water with a little Murphy’s oil soap and vinegar along with 0000 grit steel wool to clean oak adirondack chairs that had molded outside. It worked really well and got them clean. I then ingorantly used this same technique on my finished white oak banister to try and remove the oil and dirty from the hand rail. This was a complete failer. Some areas look clean and perfect while others have turned grey. I don’t know where to start…any help would be great
Reply to Erin Tackett:
Good Morning Erin,
Thank you for getting in touch with your enquiry. Whilst Vinegar is good for many things, I would not necessarily recommend it for cleaning wood, although it depends on the type of vinegar you use, as it can react with the wood. You can use it to clean if thinned down or simply add a small amount to warm soapy water if that is what you are using to clean your floor with. Undiluted Vinegar and steel wool are often used to create a treatment that ages the wood, giving a silvered appearance or a natural patina.
You may find that this is what has occurred on your banister and I would think that sanding may be the best way to restore the natural colour of the wood. If the effect has penetrated fairly deeply then Fiddes Oxalic Acid Crystals may also be worth considering, a test area is strongly advised.
I also would not advice using steel wool on oak, or other woods such as Iroko or Teak as often little particles of the steel get caught in the wood and over time react with the tannins in the wood and cause black or blue staining to the wood, that is difficult to get out.
I hope that helps and please do not hesitate to get back in touch via our contact us (https://www.wood-finishes-direct.com/pages/contact) page.
Kind regards Samantha.
Hi I am thinking of buying a deeply carved antique table and chairs made of oak. They have many years of dust buildup. The top of the table is deeply carved with glass sitting on top so it can be used. It is going to be very hard to clean and I do not know what finish is on it. It looks like it could use a high pressure cleaner on it to clean out all the crannies but I have been reading comments above and noticed that water will turn it black. I have no idea how I am going to clean this if I go ahead. Thank you
Reply to Kerry:
Good Morning Kerry,
Anything with a lot of detail and carving can be difficult to clean and not knowing what the current finish is makes it that little bit harder also. A pressure cleaner may be an option, however its not one that I would necessarily recommend as it could damage the current finish. And if the table is of value, then care will need to be taken and you may have to work by hand to get the wood clean.
We have a great range of cleaning products suitable for wood and wood finishes Cleaners (https://www.wood-finishes-direct.com/collections/wood-cleaner) but you will need to work out which is best for your project.
If you have any questions or need further advice please feel free to email direct via our contact us (https://www.wood-finishes-direct.com/pages/contact) page.
Kind Regards Samantha.
Hi
I have an old dark oak pot cupboard. I would prefer this to be a lighter or golden oak colour. How would I do this please?
Reply to Rachel:
Good Morning Rachel,
Oak is not generally a dark wood and so perhaps there is a finish or stain of some sort on it? Perhaps you could sand a small area to see what the result is, if the natural colour of the wood is lighter.
I would be happy to take a look at some photos, you can send then direct to wfd.advice@wood-finishes-direct.com and I will be happy to advise you further.
Kind regards Samantha.
Hi
We have had a 300 year old ish Oak beam from a Barn and have cut & smoothed it down for a mantel over a stove, we have treated woodworm we think successfully but we think any we have missed will die with heat from a stove which will now be on for 3-4 months daily.
Can you offer any advice on products to use to keep it looking a similar colour to original but will be safe and not dry out and look awful near heat.
Many Thanks
Reply to Doug:
Good Afternoon Doug,
It will be difficult to keep a piece of wood that age totally natural and unchanged, the age of the oak is highly likely to result in some considerable darkening when you apply a clear product to it. There are things you are able to do to reduce the darkening, use a water based product that sits on the surface rather than an oil that penetrates, or consider an oil with a minute amount of white pigment in it to reduce darkening, however until you try your test area it can be difficult to predict how this oak will react.
Manns Extra Tough Interior Varnish (https://www.wood-finishes-direct.com/products/manns-extra-tough-interior-varnish) is a water based product that may suit your needs, it comes in a range of sheens and in sample sizes to allow you to test first. It will withstand some heat, although direct or long term exposure may shorten the life of the varnish and increase the chance of flaking. Should flaking occur you are likely to need to sand back to bare wood to re apply an all over even finish again.
The alternate is Fiddes Hard Wax Oil Natural (https://www.wood-finishes-direct.com/products/fiddes-hard-wax-oil-oak-lightening) this is an oil that absorbs into the wood and dries hard to give a durable protective finish. I would expect this to darken slightly, even though it is designed not to, how much you will not know, again until you try a test area first. The benefit of oil application is the ease of maintenance, as the oil wears away you are able to top up with a refresher coat, with out the need to sand back, just ensure the surface of the wood is clean, dry, grease free and ready to take on and absorb more oil. Again heat may reduce the life of the oil, this depends very much on how close and how hot the exposure is.
I hope that helps and if you need any further guidance please do not hesitate to get in touch via our contact us (https://www.wood-finishes-direct.com/pages/contact) page.
Kind Regards Samantha.