Decking oils protect, nourish and preserve wooden decking from weathering, foot traffic, stains, dirt and other surface contaminates. With many types of softwood and hardwood decking available, it’s worth taking the time to get the right oil for your garden deck.
Types of decking oil
Choosing the right 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.
Why use oil?
Softwood decking boards made from pine, larch, fir and spruce come from faster growing, evergreen or coniferous trees. These timbers are extremely durable but require oiling to provide long-term protection against weathering and water ingress. Hardwood decking is naturally more resistant to weathering but should still be oiled to waterproof and protect it from water ingress and the long term effects of weathering.
Oil-based decking treatments penetrate into the wood grain and dry to form a tough, durable, water and weatherproof barrier that beads rain and allows run-off, rather than allowing water to soak in and damage the decking boards. Other benefits include…
- Helping to prevent decking boards from cracking, splitting and warping by keeping them nourished and supple
- Helping to keep wooden decks clean by preventing dirt and grime from becoming ingrained in the surface grain of the timber
- Protecting decking from the bleaching effects of the suns UV rays with fade resistant pigments and UV filters
- Added slip resistance with anti-slip decking oils to help keep decking safe even when damp or wet
- The ability to change or restore new or old decking boards by staining the wood with a coloured decking oil or oil-based decking stain
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.
Top 3 clear (Natural) decking oil treatments
- Ronseal Decking Oil Natural (Clear): An all-in-one, solvent-based oil for all bare wood, preserved or pressure treated softwood and hardwood decking boards. Contains UV filters to protect against sun damage and helps to prevent mould, mildew and fungi growth
- Ronseal Ultimate Protection Decking Oil Natural (Clear): A water-based deck oil for all bare wood decking. Offers up to twice the resistance of standard oils with excellent water repellency and rainproof in just 90 minutes. Contains UV filters to protect decking from sun damage and colour fade
- Barrettine Nourish and Protect Clear Decking Oil: An advanced-formulation solvent-based oil that nourishes and protects decking and other garden wood. Contains a biocide preserver to protect against mould and added UV fade resistant pigments to protect decking from the sun’s damaging UV rays
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.
Pigmented or Coloured Decking Oils
Using a coloured oil or oil-based decking stain is a great way of changing or restoring the appearance and character of decking. Available in a wide range of colours, oil-based decking stains are a great way to restore the appearance of old, tired and grey looking decking. Coloured decking treatments offer better 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.
Available in both clear and coloured formulations, the following oil treatments are suitable for both softwood and hardwood decking.
Top 5 Oil-based decking stains
- Ronseal Decking Oil: A long established and proven product that offers excellent value for money and available in a range of colour shades
- Holzol Decking Oil: A trade quality, all-in-one decking treatment suitable for all wooden decking. Available in clear and a range of attractive wood-tone colours
- Osmo Deck Oil: A German manufactured, premium grade deck oil suitable for all softwood and hardwood decking. Available in a wide range of colours including grey and black
- Manns Premier UV Decking Oil: A multi-purpose exterior decking treatment. Unique UV formula resists the greying effects of the sun. Wide range of popular colour tinted finishes
- Barrettine Decking Oil: An advanced formula that nourishes, protects and stains wooden decking. A wide range of colours to enhance and protect wooden decking
Anti slip decking oil
Ideal for decking steps, slip-resistant or anti-slip decking treatments 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 treatments
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 Quick Dry Textured Decking Oil: A water-based, anti slip decking oil for use on composite, softwood and hardwood decking. Contains UV (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 oil to enhance the natural colour of the deck or a colour tinted 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.
When choosing a decking treatment, review each product to make sure that it meets your project requirements in terms of colour, price, coverage and application. Read independent customer reviews to get an indication of durability, value for money and any other points that will help you to make an informed decision before buying.
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.
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 oil-based decking treatments require just two thin 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 oil.
Before buying, 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 treatment 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