The popularity of decking across the UK is relatively recent, providing an attractive and elegant area to sit out, especially during the summer months. The investment in a decked platform in your garden can be significant, so looking after the wooden surface is important to keep it in great condition. So then, how can you clean decking with a pressure washer?
Pressure washers are very powerful and can cause damage if used to clean decking. Always ensure that you work at a lower pressure setting if you choose to clean the deck with a pressure washer, and avoid getting too close to the surface – at least half a metre away with a fan nozzle or alternatively utilising a broom attachment to reduce the risk of damaging the surface.
Is A Deck Cleaner Better Than A Power Washer?
As you can see in our pressure washer reviews, petrol powered models can deliver incredibly strong jets with the default nozzles – in some cases up to 4000PSI. That’s likely to cause damage to the wooden surface of your decking, especially if you are regularly using the machine to clear gunk from the grooves in the surface.
While power washers make the job feel really easy, it’s far better to use a specialist deck cleaning product first, and resort to the pressure washer if you find that you need a little more power. Deck cleaning detergents are available in many local garden centres, especially the large out of town brands like Screwfix, B&Q and Wickes. You simply follow the instructions to use the detergents in a bucket, sometimes ready to use but more often needing diluting with water.
You then use a brush with sufficiently strong bristles to spread the solution across the surface of your decking and just like washing up the crockery in the sink, the cleaning detergent helps to break down the dirt and other grime that’s attached to the wood. Most detergents need to be left on the surface for around a quarter of an hour do work their magic, and if you’ve got green growth from the likes of moss like algae on the wood, you may even need to leave it for a day or two to kill it off. Always read the label though, to make sure there’s no risk to damaging the wood itself. The majority of detergents are formulated to be safe for longer applications though.
To rinse the detergent away, it’s fine to use a pressure washer on a weak spray setting, ideally using a spray nozzle rather than one of the more powerful targeted jets.
What Are The Best Deck Cleaning Detergents?
There are a huge number of detergents available that are marked as suitable for wooden deck cleaning. While it’s easy to pick them up at a nearby hardware store or garden centre, Amazon will also deliver them to your door. Here’s some popular choices on Amazon available now:
Pro-Kleen 260735 Ready to Use Simply Spray & Walk Away Green Mould and Algae Remover (1 x 5 litres) Patio, Fencing and Decking Cleaner, Multi
Path Patio Decking Cleaner | 5 Litre | 250 sq.m | Kills Mould Algae Moss Lichens Black Mould Remover | Bleach Free | Outdoor
Pro-Kleen MY16 Patio Cleaner Simply Spray and Walk Away Green Mould and Algae Killer for Patios, Fencing and Decking 5 Litre Concentrate (Makes 25 litres)
Do You Have To Clean And Rinse Decking Before Painting Or Staining?
When the time comes to treat the wood again on your deck, you’ll want to make sure that you’re working with a clean and dry surface. That means you’ll get the most attractive surface, giving an even and consistent finish.
If you paint the wood treatments over dirty decking, you’ll see the bumps of the grime get sealed into the deck, making it near impossible to resolve later. Decking typically has a consistent finish with each wooden strip, often with ridges and sometimes indented patterns. These are to improve the grip for people walking on the surface, not just to look amazing. When decking is wet it can get quite slippery, do these ridged surface patterns are often used to reduce the chance of slips and slides happening – particularly in wet weather.
If you don’t do a thorough job of cleaning the decking before painting or staining the wood, you’ll almost certainly reduce the effectiveness of these safety measures, as well as leave it looking sub optimal.
When we talk about painting the deck, it’s worth noting that we’re referring to treatments designed for decking, painted on to treat the surface, not any old paint like you’d use on the walls in you’r living room. Emulsion paints designed for internal walls won’t stand the test of time in the rain and exposed to the elements, and exterior paints like those used for drainpipes and some types of guttering aren’t going to give a good finish that’s suitable for walking on. Always use products that are intended for use on wooden decking to get the finish you want, even if it costs a few extra pounds.
How Often Should You Clean Decking?
It’s a god idea to clean the decking at least once a year, particularly when it warms up in the spring. You’ll want to make sure you don’t start thinking about getting it tidied up why you’re still getting sub zero nights, as this will risk ice forming on the surface. That’s both a safety hazard and also not great for the wood – especially if the protective seal from the last coat of stain has degraded. You want to have a warm day so that the wood can dry out again in reasonable time, and be ready for a new wood treatment if required.
Remember – always wait for wood to fully dry before painting any treatment on that creates a waterproof seal. While it’s likely that drying will still be possible from the underside of the planks, it can take much longer once the new treatment is applied.
Should I Sand Down Decking After Cleaning Before I Paint?
If the surface of the deck is in really good condition, it may not be necessary to sand it down. However, remember that when you stain the deck, it will lock in any scuffs and rubbed areas, so if there’s any sections you think could look better will a little effort, now is the time, before you start to treat the surface and protect it from rain which could cause the surface to warp, crack and otherwise deform.
Stay On Top Of Deck Cleaning
Regularly checking your deck for signs of mould, mildew or algae is wise as catching it early means it’s much easier to remove. In addition, regularly clearing leaves and twigs that are dropped by birds or fall from trees help is a great idea too. A lack of debris on the surface allows it to fully dry quicker, so it can be quickly swept away rather than forming an ever growing mass of gunk as it repeatedly gets wet in the rain and dries in the sun.
A regular routine of deck clearing can seem like a pain, but it’s much quicker than dealing with the cumulative damage later.