Should I Oil My Deck?

To oil or not to that is the question… The answer is “whatever the client wants”

“If you want your deck au natural that’s fine, if you want to look as new as it did on first installation then that’s fine too”.

It is clear that in many cases, products are being selected and applied to timber that is either not protecting it from the elements, not performing as end-users had expected or at worst both!  There is an ever-increasing requirement to apply penetrative coatings onto timber, especially hardwood species, as these not only preserve the longevity of the wood but also provide a very aesthetically pleasing appearance too.

Common issues that are presented on a regular basis:

My deck is made of Hardwood and I have been told that it does not need treating, is this true?

Certainly not! Whilst hardwood is of course denser than softwood, it still transforms moisture content and therefore will move when exposed to the elements.  You should always treat timber hardwood or softwood.

What is the best finish to apply to my deck?

Should I Oil My Deck?

The best way to treat decking is to use a product that does not film-form.  The majority of products in the market today produce a micro-build on the surface of the deck and as this is a timber structure that has to cope with high traffic in the majority of cases, these types of products will simply wear and peel off.  Owatrol solutions such as Deks Olje D1 & D1 ProTextrol Oil and Aquadecks are all penetrative products meaning that they saturate the timber and therefore cannot peel or flake, providing the timber has no mill glaze, prepared and the oil correctly applied. It also makes maintenance a much less laborious task as you do not need to remove the previous coating.

What is “Mill Glaze”, do I need to remove it before treating my deck?

New timber frequently has mill glaze (a shiny finish caused by a combination of timber planning, wood oils, resins etc. during manufacturing ), which prevents the proper penetration of practically any finish.  In effect then the pores of the timber are closed by the planer blades and may take several months of exposure to the elements to open again.  By the time this has happened though, the rainwater will have penetrated and without protection, the wood will move and become distorted.

A simple and effective way to ensure that the mill glaze is removed before treating the wood is by using a 50-50 dilution of Prepdeck and water and scrubbing this into the deck.  Rinse it away after 30 minutes and then apply a 25-75 mix of Net-trol to water respectively to neutralise the surface and the timber is ready to be treated with a penetrative coating.  In some cases, this may not be necessary and many professionals will not have removed mill glaze, however, our advice, especially on hardwood and exotic hardwood species especially would be to always clear mill glaze before applying and Owatrol coating.

Can I prevent my deck from going grey from the weather?

You can but to do so you will have to apply a product that does film-form.  Any penetrative solution, be it from Owatrol or other manufacturers, will always be prone to weathering.  With Owatrol products, this is not something to worry about in terms of damage to the deck.  It is a natural phenomenon caused by exposure to UV Rays and is only affecting the surface of the deck.  Owatrol products protect the wood from the moment you apply them and as long as you maintain the deck as directed, it will continue to do so for as long as you have the deck in situ.

My finish is flaking and it has not been applied for very long ago.  What can I do?

Sadly this is a common call that we receive and in many cases from referrals from key manufacturers to the end-user to strip the finish and start again.  The fact is that the only way to resolve this issue is to remove the old finish in readiness for the new and you have two options.  First, you can spend many hours sanding the surface until you have completely removed the coating and brought the deck back to the bare wood.  Or a more simple solution is to use a stripping agent such as Owatrol Prepdeck followed by Owatrol Net-trol.

Prepdeck will remove coatings such as stains, varnishes, paints etc. in a single application and you have to then apply Net-trol to neutralise the effects of Prepdeck before applying the new finish coat.  Once the old coat is removed, it is then recommended that you apply Owatrol Textrol Oil to the point of saturation.

What can I do to prevent my deck from splitting and moving?

When sawn timber is first exposed to the external elements, it expels its natural moisture content rapidly, whilst absorbing and releasing the moisture that it receives from the environment.  This is called ‘transformation of moisture’ and is what causes the wood to expand and contract, leaving you with the damaging effects that it causes.  Owatrol Seasonite is a unique solution that is designed specifically to regulate the transformation of moisture in timber and minimise the risk of movement occurring.

My external timber has been pressure treated so it doesn’t need another finish

Irrespective of whether your new deck is pressure treated or not, it is still possible that the new wood will crack, warp, split or cup.  Pressure-treating is designed to prevent rot and decay, not movement in the wood.

My deck was treated last year but has started to peel so should I sand it back?

Of course, you can sand the timber and this will remove the previously applied coating, but this is hard work and if you’re into applying a penetrative coating, you will need to clean the dust from the pores of the timber. 

Using Prepdeck and then Net-trol will negate the need to sand your deck and cleanse the pores in readiness for the application of a penetrative coating such as Textrol Oil.

There seems to be a growing trend in having deck boards pre-stained so is this the way forward?

This depends on both the user preference and the application.  In certain cases, it will be very beneficial to have the timber pre-stained as it will save time and ensure that the wood is coated effectively.  There is a word of caution however as many of the products in the market that are used for pre-staining are micro-film building coatings which are not ideally suited to decking.  Owatrol can offer Industrial coatings and have arrangements in place for the spraying of these as well.  Our range offers penetrative coatings so far more suited to decking applications.


The range of products that can be applied to timber is vast and ever-increasing.  Penetrative coatings such as those from Owatrol, Osmo and other professional products are certainly becoming ever popular as they provide a much easier maintenance process than film forming products.

Owatrol solutions are manufactured from the highest quality raw materials and are the Professional’s choice for wood care today.  Companies such as Decking Décor are solely recommending the use of Owatrol solutions and this is a virtue of the quality that they provide.

The overriding statement, therefore, is that whilst you may be inclined to apply lower costing solutions than the likes of Owatrol, Osmo and other higher-end solutions, this will probably not be cost-effective in the medium to long term.  Delivering the right solution from the outset will deliver the best results and for the Professionals looking to develop their reputation and ensure repeat business in the future, it is the best way to guarantee this.

owatrol decking oil advice

This page was printed in Spring 2013 Timber and ecoConstruction Magazine on page 18. Whilst this page is 10 years old, the information is still current…

Ready to oil your decking?

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