What Treatment Can I Use On Oak?

Oak is one of the most low maintenance woods used in construction, although when used for exterior purposes oak still reacts to the elements. Wind, rain, and sun all effect the wood in different ways, they can bring out the natural beauty of the wood but they do change the look of the wood over time. Many people don’t want their wood to change too much and depending on the mix of the elements depends on what colour your wood will turn.

More exposure to sun will create a silvery look of the oak, which can be pleasing to the eye, whereas prolonged exposure to rain, will give the oak a blackened look as oak has a very high tannin content which as it weathers mixes with the rain resulting in a black look on the oak, tannin is what colours wine in oak wine barrels, and is also used for dying leather, it gives the wood that warm colour.

Some people don’t mind what the weather throws at their external oak, most feel it makes their building naturally beautiful and unique, but as we are often asked how should I treat my oak? What will stop my oak from blackening and going grey? We thought we’d give you some answers;

To try protecting the oak while keeping it a natural looking colour is quite hard as most clear treatments you would ‘paint’ onto oak will slightly darken its natural look (try painting oak with water this will show you roughly the colour it will turn with any ‘clear’ product. Nether the less, stick to a clear wood preserver / preservative.

For the oak to remain natural but prevent both blackening & the silver look from sun exposure you also need in addition to the above something that has a UV blocker, not unlike the sunscreen we use on ourselves! Oil based UV sealers not only block out the UV sun so preventing the silvering of your wood but also the oil will stop the water penetrating it too.

If you don’t mind mixing it up a bit and like your oak with a little colour, then these products can come in different stain colours, from natural to grey to green. You could even make your oak look like mahogany? Why you would want to beats me?

If you want to protect your oak but like the ageing silver look then you can go with a more natural approach, using an oil can nourish your wood bringing out the natural grain but most will have no sun protection so the sun will still silver the wood but the oils should prevent the water penetrating and causing the blackening. You will need to apply a wood oil more often than you would a sealer and again a lot of these products will say they do not alter the colour of the wood, they all do slightly, if you are really attached to the colour of your wood, please always test a small area first.

But what can I use on my old oak to make it look better?

If your old oak building is suffering with blackening or silvering there are many products available to remove this build up on the surface of your exterior timber. The blackening is a fungus so a fungicidal wash would be recommended. Silvering removal will need a bleaching agent, oxalic acid can be used with care, it very harsh it can tarnish metals and clean grout and needs to be tested to see what it will do to your wood, once you have it to the desired effect you will then need to treat with both the above preserver & a sealant with a UV blocker to prevent it happening again.

Please always test your product choices before applying it to your beautiful wood, also read the bottles carefully as to how to apply & what safety gear you need, some of the product are quite toxic.

These are just a few options, there are many others out there but it’s totally down to personal taste. After all of the above if you think you like it ‘au naturel’ your green oak should last you at least your lifetime, just the way it is!