Decking oils preserve, nourish and protect wooden decking from weathering, foot traffic, dirt, stains and other surface contaminates. With so many decking oil products available, it can be difficult picking the one that’s right for your garden decking.
Types of decking oil
Choosing the right decking oil and the one that best meets your requirements can depend on the type of decking you have, the desired finish (clear or coloured), budget, performance and maintenance expectation. Decking oils have traditionally been solvent-based but more water-based versions are now available introducing even more choice.
Why use a decking oil?
Softwood decking made from woods such as pine, larch, fir and spruce comes from faster growing, evergreen or coniferous trees. Although these timbers are extremely durable, they do require added protection to make them waterproof and resistant to weathering. Although hardwood decking is naturally more resistant to the effects of weathering, it too should still be oiled to make it waterproof and protected from moisture and the long term effects of weathering.
Decking oils penetrate into the wood grain and oxidise to form a tough, durable, water and weatherproof barrier. Water and rain beads on the surface rather than soaking into the grain of the wood. Other benefits of using a decking oil treatment include…
- Keeps decking boards nourished and supple
- Helps to prevent the wood from splitting, cracking and warping
- Repels water so that it beads on the surface of the deck
- Helps prevent dirt and grime becoming ingrained in the surface of the timber
- UV resistant decking oils protect the natural colour of the timber for longer, resisting the bleaching effects of the sun
- Some decking oils are slip resistant to keep decking safe even when wet
Whilst softwood decking can be oiled from new, new hardwood decking boards often need to be allowed to weather for a time before applying a decking treatment. Dense exotic hardwoods are naturally oily and have a tight grain. If an oil is applied too soon, it may not penetrate into the decking boards. Allowing hardwood decking to weather for a time allows some of the natural wood oils to dissipate and for the grain to open.
Always read the instructions from the decking supplier as the ‘weathering’ period can vary depending on the type of decking and species of wood used for the decking boards. Once the grain opens up the boards will more readily accept the oil. Some types of exotic hardwood timber such as Ipe, Yellow Balau, Massaranduba Cumaru, Iroko and of course Teak may require a highly refined or extra thin oil such as Osmo Decking Oil for the best results.
Clear decking oil
Clear decking treatments are designed to nourish and protect garden decking whilst retaining the natural character of the timber. Clear products tend to darken the wood slightly, giving an almost damp like appearance, whilst enhancing the natural grain and character of the timber. To get an indication of how decking will look when oiled, simply wipe over a section of untreated decking with a slightly damp sponge.
Although many clear deck oils contain UV filters to help protect the deck from the greying effects of UV exposure, not all do. UV filters work much like suntan creams by filtering out and protecting the wood from harmful UV rays. Although they help to filter UV rays, they don’t stop them. This means that decked areas will naturally grey over time, albeit at a much slower rate than decking treated with a non UV resistant decking treatment.
Coloured decking oil
Using a coloured decking oil is a great way of restoring or changing the appearance and character of wooden decking. Available in a wide range of colours, coloured oils are a great way to restore the appearance of old, tired and grey looking decking. Coloured decking treatments tend to offer a higher UV resistance to sun damage because of the colour pigments suspended in the oil. As a general rule, the darker the colour, the more UV resistance the oil provides. As an example, an Oak or Cedar coloured oil will provide better UV protection than a clear or natural oil.
5 of the Best Decking Oil Products
The following oil-based decking treatments are available in both clear and coloured formulations and are suitable for both softwood and hardwood decking. Click on each to see full product details, decking oil reviews, buying option and more.
- Ronseal Decking Oil: An long established product that offers excellent value for money
- Holzol Decking Oil: A trade quality, all-in-one decking treatment suitable for all wooden decking
- Osmo Deck Oil: A German manufactured, premium grade deck oil suitable for all softwood and hardwood decking
- Manns Premier UV Decking Oil: A multi-purpose exterior decking treatment. Unique UV formula resists the greying effects of the sun
- Barrettine Decking Oil: An advanced formula that nourishes, protects and stains wooden decking
Anti slip decking oil
Ideal for decking steps, slip-resistant or anti-slip decking oil products contain small particles within the oil that bond with the surface of the wood to create a microscopic textured layer. These oils are perfect for raised decks with steps and especially ideal for commercial premises such as pubs, restaurants, garden centers and clubs where safety is a top priority.
Anti slip oils work because they contain fine particles within the oil that when dry, form a slightly textured surface. Although too small to see, the dried oil provides improved friction and grip between feet, shoes and the surface of the deck.
Recommended anti-slip decking oils
Although Anti-slip treatments tend to only be available in ‘clear’ formulations, they can be applied over a coloured deck oil once it has dried to provide a coloured finish with slip resistance properties.
- Rustins Textured Decking Oil: A high quality, clear anti slip oil for use on softwood and hardwood decking. Contains Ultra Violet light inhibitors to protect decking from sun damage
- Osmo Anti-Slip Decking Oil: A high quality, anti-slip decking treatment for all garden decking. Perfect for decking steps and decking situated in commercial areas such as pubs and restaurants
- Barrettine Anti-Slip Decking Oil: A premium quality deck oil for use on all types of wooden decking
What is the best decking oil?
Deciding on which is the best decking oil largely depends on the individual project, the desired look and performance. Some factors are straight forward such as whether to buy a clear decking oil to enhance the natural colour of the deck or a colour tinted decking oil to add character or to achieve a specific look. Other factors to take in to consideration are do you require UV resistance, protection against mould and algae or slip resistance.
How and when to apply decking treatments
Applying an oil to new, bare wood decking is quick and easy. Simply follow a few simple rules and your new garden decking will look amazing in no time.
- Sweep with a stiff broom to remove any lose leaves and other surface debris
- Ensure that the decking is clean and dry
- Treat any mould or algae (green or black patches) with a suitable decking cleaner. A second application may be required if the decking is heavily soiled
- Apply the oil thinly and evenly working it in to the grain of the timber – avoid pools of oil on the surface and wipe of any excess
- Wait the specified drying time on the tin before applying a second coat
Most decking oils only require two coats. Although there may be a temptation to apply three, four or more coats, this can actually cause a number of issues such as.
- Extended drying times of days instead of hours
- A sticky or tacky finish that will not fully dry
- A surface skin or film that is easily marked or peeled off
- Increased risk of dirt or debris stuck in the finish
If wooden decking hasn’t been treated for a number of years and is exceptionally dry, it may absorb 3 coats of oil. After applying the recommended amount stipulated on the tin, wait a couple of days and try a thin third coat on a small test patch. If the third coat is absorbed by the deck and dries normally, it’s probably OK to apply a thin third coat. If the oil on the test area beads or sits on the surface, does not dry or remains sticky after 24 hours, it’s an indication that the timber has taken as much oil as it can and is not ready for more.
When to apply a decking treatment
Ideally, oil treatments should only be applied when air temperatures are 10 degrees centigrade or above. It’s also best to wait until it is forecast to stay mild and dry for at least 24 to 48 hours. Although most deck oils are touch dry in just a couple of hours, most need several hours before they provide full protection against rain, foot traffic, dirt and liquid spillages. Spring, Summer and early Autumn are the ideal times to treat decking.
Autumn Decking Maintenance
In addition to applying a fresh coat of oil in spring, it is also recommended to apply a maintenance coat or 2 before winter sets in. Oiling a decking in Autumn will help to protect decking boards through the cold, wet, winter months when snow, ice and freezing rain can damage the wood.
When is a deck oil not suitable?
Wood oils work by penetrating in to the surface of the wood grain where it dries. This cannot happen if the decking has been treated with a decking paint or varnish like decking stain. These types of decking treatments seal the surface of the timber with a film-like coating therefore preventing the oil from penetrating into the timber.
Cleaning and preserving decking
Once oiled, decking should be routinely cleaned with a dedicated decking cleaner. These products are designed to clean the surface of the deck whilst preserving the decking finish. Household detergents and cleaners, including washing-up liquids should never be used on wooden decking as they are designed to break down and remove oil, stains and grease from surfaces. household cleaners will degrade and eventually strip the oil from the decking boards leaving the wood unprotected and exposed to water and dirt ingress.
For decking where the oil-based finish has degraded to such an extent where it no longer repels or beads water, it is recommended that the decking boards are thoroughly cleaned with a decking cleaners and restorer before re-treated with a suitable decking oil.
Before buying a decking oil, we always recommend that you read any decking oil reviews for a given product. Customer reviews often give more of an insight into the type of colour or finish to expect, how well it performs and an indication of value for money. Buying a cheap decking oil maybe a false economy as well established brands are likely to perform better and last longer.
For information on decking preservers, see our decking preserver page.
Other wooden garden fixtures
In addition to decking, garden sheds, fences and garden furniture also require care and maintenance to keep them mould and algae free, looking good and protected from weathering. Find out more about garden shed treatments, garden fence treatments and garden furniture treatments, including preservers, cleaners, varnishes, paints and oils at home-gardener.co.uk