ALPHA oak Framing Ltd
Materials and Finishing
All our oak, and weatherboarding materials, are sourced from FSC or PEFC certified suppliers. All the oak is inspected upon delivery for suitability. Any posts or beams not meeting our criteria are rejected for replacement.
Oak is a naturally durable timber, which requires no further treatment. It is an attractive, strong and sustainable material, which improves with age. As it dries it situ, it will blend into its surroundings, as it weathers to a beautiful silvery-grey.
The frame will continue to strengthen as time passes, giving you a building that will stand the test of time.
We ensure that the exterior envelope materials used are complimentary to the frame, and the natural surroundings.
Oak or Larch cladding will fade to a silvery-grey, blending seamlessly with the oak frame.
Glass panels used will reflect the environment around the building, and allow for beautiful sceneries on any day from within.
Finishing & Treating Oak
With regards to finishing and treating oak there are plentiful options, but there are frequently asked questions. Commonly, we are asked how external oak can be kept looking natural, when the build is finished. Whilst the question is easy, the answer is not so. These are the essential considerations :-
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When water penetrates oak, it reacts with the tannin naturally in oak, resulting in 'blackening'.
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The sun's UV rays turn the oak to a silvery grey over time.
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Clear products are inevitably not completely clear so they tend to 'bring out' the natural colours of the oak, making it darker and a warm golden colour.
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The wind, rain and sun will make a difference to how quickly the oak changes colour.
If the desire is to keep the oak looking as natural as possible, but to prevent blackening or silvering as much as possible, then the following is the best method we know of :-
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1 coat of clear wood preservative
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Followed by 2 coats of Osmo UV Protection oil 420 extra
Osmo 420 extra offers UV resistance and contains biocide which is important for external oak, 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 desire is to protect the oak whilst maintaining the silvery appearance then the following is the best :-
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1 coat of clear wood preservative
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Followed by 3-5 coats of Tung oil
Tung oil is one of the clearest oils on the market and doesn't give UV protection.
If you want the exterior oak to be coloured, then the following method is advised :-
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1 coat of clear wood preservative
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Followed by 1 coat of your chosen colour of Osmo natural oil wood stain
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Followed by 1 coat of Osmo UV Protection Oil 420 Extra
If blackening on exterior oak needs removing, then a wash with a fungicidal wash is suggested. If you wish to remove the silvering, a scrub with Osmo wood reviver, or an Oxalic acid is recommended. The crystal form is better, which dissolves in warm water. It is important to follow the instructions and advice from the manufacturer when using this. It is advised to have a practice with the Oxalic acid first, before attempting your frame.
Another common enquiry we get is how to keep internal oak looking natural. You cannot just apply "clear products", as this will bring out the natural colours of the wood, and make it darker and more golden. A good way to see how your oak will look once it has been finished with a "clear" coat is to apply water to an offcut. The look when the wood is wet is very close to how it will look with a clear varnish or oil applied.
Some clients like the way oak colours when clear coatings are applied, while others want it to look as natural as possible. This natural look can almost be achieved by adding some white to your chosen top coat, but a test on an offcut is a MUST, because each wood needs a different mix of clear top coat to white.Here are some guidelines :-
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If an oiled finish is preferred, then apply two thin coats of Hard Wax Oil Natural or Polyx Oil Raw.
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Alternatively, you could make your own mix, using white hard wax oil with 2 parts of the clear hard wax oil.
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If a varnished finish is favoured, then 1-part white dye can be mixed with 50 parts clear varnish.
Clear wax polish is the one exclusion to the above... If a clear wax polish is applied to bare oak, then the colour is kept very natural indeed, the only question is whether a wax polish is going to be durable enough. Internal doors are considered ideal for finishing with a wax, but a floor may look nice when waxed, but regular upkeep is needed, so most people don't go for that.If the desire is for the oak to be made darker, then hard wax oil is perfect, because it colours and protects the wood in one go. It's a good to finish with a clear coat, because if the wood gets scratched, then it is the clear coat that scratches first, and not the coloured coat, hence the scratch wood not be noticeable.
Oiling consideration:
If oak is being oiled then it is best to sand it with a sandpaper that is no finer than 150 grit. This opens the pores of the wood, and allows the oil to penetrate the wood better, giving a greater protection.