How to Clean and Oil your Deck
A year ago I installed this deck for a new hot tub. It’s had everything thrown at it this year - mostly incessant rain, and a few extra surprises and was desperately in need of refurbishment. So in the video above I show you how I’ve got it looking brand new again. I’ll be running through the process of cleaning and oiling your deck, and putting some of the UK’s leading deck oils to the test in a head to head comparison to tell you which one I think is best for your deck.
But before I start, I’m always looking for ways to make this sustainable now I’m doing it full time (and particularly given how much I’m having to spend on kit for each video - £150 alone today on the decking oils and hardware), so if you like my content and to help me keep providing it here on this channel for free, I would be so grateful if you could visit my Patreon page, to support me. For just £5 per month, you have daily contact with me through my Discord member forum behind the scenes videos and automatic entry to my free monthly giveaways. Please click here.
The before picture. . .
Why didn't I oil my deck when I installed it?
Partly because I knew it was pretreated and wanted to get the hot tub up and running for the kids but I’ve since learnt that it’s best to leave a newly laid deck for 6 months before being stained or oiled, as most decking comes pre-treated or tannalised, and you want this to erode so that the oil can sink in properly. Clearly if your deck isn’t pre-treated you can start straight away!
So, why do I need to oil it now?:
Well, it’s actually weathered pretty well over the winter, but you can see from these images, that the deck was looking a bit tired, mostly just dirty and a bit green in places. Also, I got a nasty surprise when I lifted up the insulated mat I laid back in August, to find the foil had delaminated under the pressure of the water above it, and the deck was looking slightly rotten underneath because the water under it hadn’t been able to properly drain away. Luckily the damage was only superficial.
What kit to use?
I have a lot of tools, but I didn’t have any designed for deck cleaning, so I thought I’d go online and see what was available and I came up with the following. I bought this Osmo deck cleaning brush and telescopic pole from Wood Finishes Direct, and I picked up this Ronseal Deck Cleaner and Reviver in my local timber merchants a few months back.
I’ll come onto the oil in a bit, and I’ll let you know what I thought of each.
* The Amazon and Wood Finish Direct links above are affiliate links. It doesn't cost you anything to click on them but I do earn a small commission if you do.
And here's the legal bit I have to state: As an Amazon Associate I earn from qualifying purchases.
How to clean it?
I bought this Ronseal Deck Cleaner and Reviver a few months back, when I was researching my “which way up to install your decking” video. It says on the instructions to pour it directly onto the deck, which I did with this jug which would have been quite an economical way of doing it if I hadn’t kicked over the half full jug twice during the cleaning process.
Scrubbing brush
The deck cleaning brush which I initially thought was a bit small was actually the perfect size to scrub each plank and the telescopic pole, which I was a bit annoyed having to buy - it’s a shame Osmo don’t make the scrubbing brush to fit all decorators extension poles, of which I have a few - did grip the brush securely without any twisting or movement, and saved me a lot of back breaking scrubbing on my hands and knees as I would have had to do with a traditional scrubbing brush. Where the foil was too well adhered to the deck, I used a decorator’s knife to scrape it away. They say you’re meant to scrub in the direction of the grain, but I didn’t pay any attention to this as each board has been randomly laid and it would have been a headache to work out the direction of each board.
I was initially a bit sceptical about how well this detergent would work, particularly given the state of the deck below the tub, but I needn’t have been and a combination of that and the brush had an almost instant impact.
Ronseal say to leave the reviver on for 15-20 minutes. How long you leave it will depend on the weather. Mine started drying pretty quickly.
And so I worked in small sections, pressure washing off each section before moving on to clean the next. And when the deck was done and drying out, I went over a couple of areas again, which I had evidently not quite cleaned thoroughly enough.
Pressure Washers
Let’s have a quick chat about whether you should or shouldn’t use a pressure washer to clean your deck. A lot of people say you shouldn’t because it furs up the grain of the timber, and I can see what they mean by this. For my deck where I only really needed to rinse off the deck reviver detergent residue rather than bore out the dirt, you could say a hose pipe would have sufficed. But I’ve actually got a pretty rubbish pressure washer - this Karcher is designed for bikes and motorbikes and is sufficiently gentle that I can put my hand in front of it without it hurting, so it was perfect for the job. You find the deck reviver penetrates quite deep into the wood and produces quite a lot of soap residue which needs to be thoroughly removed before you can oil your deck, and I did find this quite a long process and probably didn’t remove all of it.
So whether you use a pressure washer depends what type you’ve got and how badly degraded your deck is. If you do furr it up, it’s not a big deal as you can always gently sand it, as I did here with my random orbit sander where there was some residue from the ecotherm foil insulation still adhered to the surface.
And after all that cleaning, I was amazed to find the deck was pretty much in a pristine condition again!
What oil to use?
Now choosing the right “oil” is actually the trickiest part of the job, as I found out when I came home from a timber merchants with Ronseal’s Ultimate Protection decking oil to find it’s not an oil at all, but a water based product! So much for doing exactly what it says on the tin (thanks to Ashley Brooks for that gag)!! There was me falling like a mug for the “Ultimate Protection” marketing gimmick!!
So the first thing I did was sound out you lot through a post on my YouTube Community page, and I got a wealth of information and opinions back (over 115 to be precise) - and I massively recommend them out yourself, I’ve linked the feed here, but to summarise:
I’m afraid there wasn’t much love for water based decking products generally, from those of you saying they just don’t last, to a paint chemist specialising in water based products saying only use solvent based on decking
And there wasn’t much love for the Ronseal Ultimate Protection which in Nigel’s experience only lasted 6 months, and others have said has a tint - a horrible yellow colour. And indeed it’s a fact that the Ronseal clear has a slight pigment in it, which gives it its UV protection
Osmo (but no UV), Barretine, Liberon & Manns the stand out
The next thing I did was stumble on some seriously good advice, when I clicked on Wood-Finishes Direct, initially just to buy the Osmo cleaning brushes. They haven’t paid me anything to mention them in today’s video but they did give me a 10% discount on the stuff I bought for it - basically all the Osmo kit and the Manns UV oil. So thanks to Ben in creative and Alison in technical, because much of what follows comes from what they told me.
I’ll give you my thoughts today but what you need is an entirely personal choice, based on:
The condition of your deck
Whether you want an easy to complete maintenance that needs regularly redoing or a more comprehensive one that you can apply and forget for a few years
Whether you want a stain or a sealant
Whether colour is more important to you than performance
UV protection or the non-UV grey look
My most to least favourite decking oils
You’ve got to factor in the increase in performance of some water based and the decline in performance of some solvent based. So a sneak peak of what Wood Finishes Direct found out in their trials - and I stress they haven’t published the results yet so this may change:
First up we’ve got Manns Premier Decking Oil
It’s solvent based
And was found to be the best all rounder.
It’s Meant to be truly clear in spite of the UV protection - I’ll let you know my thoughts on that
It got 5/5 for stain resistance and durability
Achieved a High application per m2 - I’ve used up half the tin doing two coats on this 13sqm deck
Comes in a tin like Liberon and Osmo - meaning you can mix it properly
Barretine - another solvent based oil. Also offers UV protection in a clear varnish and has marginally less performance than the Manns whilst still being a high performer
Osmo - the most durable but no UV protection
Ronseal Ultimate Decking Oil - best water based all rounder
Tikkurila - cult following but decking oils aren’t core to their business so are they investing as much time and research as the others…
Manns Premier Decking Oil
Treatment of my Deck with Manns Premier UV
So on the back of this advice I decided to buy a 5l tin of the Manns UV decking oil in clear, as I wanted to keep the colour of the deck as close as possible to the untreated original.
I also bought this Decking Brush and Tray set. If you’re used to using a 10L paint scuttle you’ll find this tray ridiculously small and flimsy, and easy to slosh oil out of when moving it around the deck. I got used to it, but suggest if your deck is larger than mine, you might want to invest in a decent paint scuttle.
The brush obviously fits the Osmo telescopic pole, and with it the oil just went onto the deck effortlessly. You’re meant to wipe off the excess using a microfibre cloth, but whilst I had one ready, such was the porosity of the deck and the control of the brush in applying just the right amount of oil, I didn’t need to.
The deck was now looking pretty good, and with one coat on you can already see the benefits of the oil, with the rain the following day beading nicely on the surface.
And I used this Osmo brush cleaner and thinner to clean the oil off the brushes. You’ll find after a couple of days the oil and thinner separates, allowing you to recycle much of the thinners for next time.
But what about the colour. This is meant to be truly clear in spite of the UV protection, and the UV protection in all these oils and water based products is like a pair of sunglasses protecting the wood, which tends to involve the introduction of a pigment that can give the wood a yellow or other tint.
Well, at first site, you can’t deny that it does have a bit of a yellow tint, particularly when compared to my 2 year old fence which has never been retreated. However compare a piece of the deck that’s been sat under the eaves of the garage but otherwise weathering, and the two look pretty similar. So I’m pleased, particularly as I’m more worried about protecting the deck than any aesthetic considerations.
The final result!
Ongoing Maintenance
And a final quick point on maintenance
Regular sweeping (or in my case using the leaf blower) to remove pollen, sap, dirt, bird faeces etc. If these things sit on the deck, when it rains you have an ideal breeding round for mould, mildew and other nasties to grow and feed on them
If you can, carry out a yearly clean and revive like I have, and top up on the oil treatment
And if your deck is grey and sun damaged you can revive it with Osmo gel or Fiddes Crystals - the crystals working out cheaper.
In conclusion…
So where does this leave us and what are my conclusions? Well, given the superior wax enhanced properties of the Osmo and its peerless durability (by over 50% the most durable and stain resistant in the trials), I was actually going to suggest this as my no.1 pick, because I’m not particularly bothered about UV protection, but I am bothered about protection from the weather and would rather not have to re-do this every 12 months.
So this would have been the order with Osmo at number 1 down to Ronseal at number 5.
However I just checked the online prices and the Osmo weighs in at a whopping £55 for 2.5l so over £100 for the 5L I would have needed. So on that basis, I’ve revised my listings, and got the Manns I used back at no.1, with the Osmo relegated to second equal. Yes you’re paying for the brand, yes it goes further and has the wax protective layer but I just can’t decide whether I’m happy to pay 4 times as much for that privilege, given I’ll probably have to treat my deck every 2-3 years anyway.
And what about the water based treatments. Well, it’s the way things are going and I do salute Ronseal for embracing the future and trying to get it right now as I suspect in 10 years time we’ll all be having to use water based products, or perhaps by then it will be composite decking removing the need for any treatment. But right now, it’s not cheap (my tin actually cost £46 as against £30 at Wood Finishes Direct) and so even with its environmental credentials, I can’t be putting a water based product that just sits on the surface onto my deck as I’m pretty confident it won’t last anything like as long as the solvent based alternatives. For completeness I should point out that Ronseal also do a solvent based version, and I understand it’s a good product performance wise given the price bracket without doing anything too flashy!
Final points
So a couple of final points. I’ve compared 5 oils today - I was hoping to include Osmo’s anti slip oil as I was intrigued to see what this was like but unfortunately Wood Finishes have in error sent me a standard oil instead, so I’ll leave that until next time, and actually, if you look after your deck you shouldn’t have any problems with it getting slippy. But inevitably I’ve missed a couple, like:
like Liberon - which also performed very well in the trials and I would say is in the same bracket as the Barrettine in performance and price.
Sadolin is I’m told of a similar quality but is at £36 for 2.5l more expensive than the Manns, Barrettine and Liberon,
and then we’ve got Tikkurila. I don’t know whether as a company they concentrate on their decking oil as much as say Manns or Barrettine, but they’ve got a cult following and at £75 for 3L a price to match. All of these (apart from the Sadolin) was mentioned by you kind people on my Community post so have a delve into those comments for more info.
Maybe let me know in the Comments section below what your experiences are with decking oils - and check out the Comments below my YouTube video and also the Community post where I canvassed all my subscribers on what oils they’d recommend?
And finally, don’t forget, regular maintenance - sweeping or use of a leaf blower is going to keep your deck looking clear and will remove all the residue that mould, mildew etc feeds off!