During the summer your decking dries out. The sun dries up any mildew and mould and the surface provides a decent grip. But the minute it gets wetter and colder, that lethal slipperiness comes back.
If you’ve ever almost killed yourself sliding around on slippery, slimy garden decking you’ll understand how important it is to know how to make decking non-slip. It’s a question we’re asked regularly, and we thought it’d be useful to write a post on the subject.


How to Stop Slippery Decking?
How does one achieve safe non slip decking? There are several anti slip decking products available.
- Anti slip decking paint
- Non slip decking varnish
- Anti slip decking oils & stains
We highly recommend antislip decking oils. Non-slip decking paints and varnishes tend to be prone to cracking, flaking and peeling off over time, whilst anti-slip decking oil and oil-based decking stains do not. In addition, anti-slip decking oils and oil-based stains are also very easy to apply, maintain and patch repair if areas become worn or stained.
Our favourite is the excellent Osmo Anti-Slip Decking Oil,which contains special compressed organic particles evenly dispersed throughout the oil. The product dries to a clear satin-matt finish to deliver a reliable anti-slip surface. It’s made from natural oils and also contains active ingredients designed to protect against mould, algae and fungus.
The great news is that this oil can be used as a top coat over Osmo and many other brands of decking oil, clear and coloured, to add an anti-slip finish. It’s perfect for exterior wooden decking and steps and works wonders on all sorts of woods including Douglas Fir, Bangkirai, Garapa, Massaranduba, Larch and common or garden Pine. And it’s ideal for any kind of decking, from the ribbed and grooved versions to the flat and smooth stuff.

Where to use Osmo Anti Slip Decking Oil?
Osmo Anti Slip Decking Oil is perfect for your home garden decking and equally good for making decked steps safe. But it’s also a great product for commercial decking in places like pubs, cafes, nightclubs and restaurants.
If someone slips on your garden deck at home, it’s unlikely they’ll sue you. But if you run a commercial operation anti-slip decking might prove your undoing, so it’s better to be safe than sorry. It might be a condition of your commercial insurance to make sure your deck is safe, and if it isn’t your insurer might even refuse your claim, leaving you liable for compensating people who have injured themselves because your deck is dangerous.
When is the Product Suitable?
Osmo anti-slip deck oil can be used on new, previously untreated decking. But you need to weather it first, leaving it untreated for 2-4 weeks in the case of softwood decking and 3 months for hard and exotic woods, and after applying 1 coat of your chosen decking oil, be it coloured or clear. This excellent product is also perfect for decking that has been previously oiled. If your deck features an oil-based finish, you’ll need to clean it thoroughly before you begin.
Bear in mind that you can’t use an anti-slip oil on top of painted decking and it won’t work over varnished or coated decks either, including many types of decking stain. If your decking has an existing finish like a varnish or a stain you need to remove it completely, which will involve either stripping, sanding or a bit of both.
When NOT to use it? Osmo Anti Slip Decking Oil isn’t suitable as a stand-alone product. You should always use it with a wood preserver and a primary decking oil.
Anti Slip Decking Stain Preparation in 8 Simple Steps
- Always carry out a test first in an area that doesn’t show, so you know how the products you’ve bought work on your particular deck. It makes doing the real thing so much easier when you know what to expect
- First clean your deck, sweeping it to get rid of every speck of visible surface debris, dirt and dust
- If there’s mould or algae present, you MUST get rid of it first. Jet washing is always a good option before treating the surface with a good quality mould and mildew cleaner
- Allow the deck to dry thoroughly
- Once treated by the mould and mildew cleaner, apply a good quality exterior wood preservative to help prevent future biological growth. 2 coats of preservative is the norm for exterior wood
- Add a single coat of good quality decking oil, either clear or tinted
- Apply one coat of anti-slip decking oil, following the instructions on the pack as well as checking those we’ve provided on our product page
- Clean your brushes and other equipment with white spirit straight away
The drying time for Osmo Anti Slip Decking Oil is 10-12 hours under normal weather conditions, longer if it’s cool or humid.
Anti Slip for Decking – Upkeep and Maintenance
You want the areas of your deck that get particularly heavy foot traffic to stay anti-slip. To stop the effect wearing off we recommend you renovate areas of wear as soon as they start to look tatty, without delay. Luckily it’s really easy – just brush-apply another coat to the worn patch.
Alternative anti-slip decking treatments
Any questions about anti-slip decking?
Need our help with your decking project?
For more information about decking treatments and their uses, contact our team of resident experts who are always on hand to help with project advice and product recommendations.
We love to see before, during and after photos of any decking, project. If you would like to share your pictures with us and our followers, send us your photos or share on our Facebook, Twitter, Pinterest or Instagram pages.
54 comments
Hi Samantha, (same as my daughter)
I intend to have a short pathway made as an extension to a patio. I will only be 1000mmx1500mm long and made from pretreated softwood with a 12- year guarantee for rot and fungal attack.
Please advise the correct procedure to follow and what quantity of anti- slip I will need of your Anti-Slip treatment.
Very Best Regards Ian
Reply to Ian Mitchell:
Hello Ian,
The Osmo Anti Slip Decking Oil (https://www.wood-finishes-direct.com/products/osmo-anti-slip-decking-oil) is an ideal product for an area that needs that bit extra protection. It is a top coat product and so you will need to add a coat of decking oil first, if you have some already, just check for compatibility of the two oils, by carrying out a test area.
If you do not have any then the Osmo Decking Oil (https://www.wood-finishes-direct.com/products/osmo-decking-oil) is ideal and the good news is for such a small area you will just need the 125ml sample tins of each product.
If you have a look at the recommendations and I am happy to help further should you have any further questions.
Kind regards Samantha.
Where can I get the non slip oil in Dublin
Regards
Pat
Reply to Patrick Scully:
Hello Patrick,
We are able to deliver to Ireland. For any orders under £50 it will be £14.95. If you go over £50 then delivery comes down to £8.95. It usually takes 2-3 working days for delivery and for more information you can call and speak to one of our friendly advisers (https://www.wood-finishes-direct.com/pages/contact).
For internal Anti Slip we have Osmo Polyx Oil Anti Slip (https://www.wood-finishes-direct.com/products/osmo-polyx-oil-anti-slip-3089-r11) and for external wood Osmo have an Anti Slip Decking Oil (https://www.wood-finishes-direct.com/products/osmo-anti-slip-decking-oil).
Kind regards Samantha.
Hi, I’m just about to put down around 30m2 of new treated softwood decking and this time we are laying it smooth side up to give a contemporary look. I’m worried about the decking being slippery so would like to use your anti-slip decking oil.
Reading the other posts, would we still need to use a wood preservative first given that our wood is treated? We also want to colour the wood, so can we use a tinted decking oil first and then put the anti-slip oil on top? Originally we were going to use a deck stain but it looks like this will not work with your anti-slip oil, so we are now considering the Ronseal Decking Oil in teak. Also, is there any advice on leaving treated wood for a period before carrying out all of this?
Thank you.
Reply to Belinda Lewis:
Hello Belinda,
Thank you for your inquiry. We do tend to advice a coat of preserver, even if the wood is ‘treated’ as it is not always known what the existing treatment protects against. Barrettine Premier Wood Preservative (https://www.wood-finishes-direct.com/products/barrettine-premier-wood-preservative) will protect from mould, mildew and rot and is a good option should you choose to apply a preservative first.
The combination or the Ronseal Decking Oil (https://www.wood-finishes-direct.com/products/ronseal-decking-oil) and the Osmo Anti Slip Decking Oil (https://www.wood-finishes-direct.com/products/osmo-anti-slip-decking-oil) would be ideal. Test areas are always recommended and if you have any further questions please do not hesitate to let me know.
Kind Regards Sam.
Hi,
If I’m applying preservative to a new deck followed by the cuprinol anti slip decking oil as suggested above, would you recommend going with a clear preservative followed by a coloured anti slip decking oil?
Reply to Matt Brown:
Hello Matt,
As long as the preservative is wax free such as the Barrettine Universal Premier Preservative (https://www.wood-finishes-direct.com/products/barrettine-premier-universal-preservative) then it will be suitable, clear or coloured essentially would be fine but the base colour will have an effect on the top coat oil, so it is probably easier to stick to a clear preservative and a coloured oil. Feel free to let me know if you have any further questions.
Kind Regards Sam.
My decking becomes incredibly slipping after rain, snow or any other way coming into contact of the wood. Would to osmo anti slip oil prevent this? or at least improve the conditions of the decking’s slipperiness?
Reply to Megan Brown:
Hello Megan,
Yes for sure the Osmo Anti Slip Decking Oil (https://www.wood-finishes-direct.com/products/osmo-anti-slip-decking-oil) will help prevent your deck from getting slippery. But you also need to keep mould and mildew at bay as this is mostly what causes your wood to get that slippery.
Keeping your deck clean and swept will greatly reduce the dangerous effects, to remove existing mildew you could use the Barrettine Mould and Mildew Cleaner (https://www.wood-finishes-direct.com/products/barrettine-fungicidal-wash-multicide). I hope that helps and feel free to get back in touch (https://www.wood-finishes-direct.com/pages/contact) if you have any other questions.
Kind Regards Sam.