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How to maintain your garden decking – cleaning, treating and weatherproofing

How to maintain your wooden and composite decking – our complete guide

A beautiful garden deck is an investment; an excellent way to extend your living space and the perfect opportunity to get outside throughout the year. Keeping a deck in great condition requires relatively little effort but helps to ensure you get to enjoy your deck for as long as possible. Knowing how to prevent and treat slippery decking surfaces can make all the difference as the adverse weather conditions begin to close in. Find out how to clean and maintain your garden deck with Arnold Laver.

How to clean wooden and composite decking

Take a read below on top tips for keeping your decking clean:

1. Prepare your decking boards for the cleaning

Move all furniture and planters away from the deck before you begin cleaning.

It’s a good idea to cover any nearby flowerbeds or potted plants, particularly if you’re planning to use a pressure washer or hose.

If mould treatment is required, take normal precautions and keep pets and children away as necessary.

2. Keep your deck clear

The most important step to keeping your decking looking its best is regular cleaning. Get into the habit of giving your decking a good brush down every week or fortnight to dislodge fresh fungal growth and any stray leaves.

A stiff-bristle yard brush is usually all you need to scrape away any unwanted growth and leaves and won’t damage your timber boards.

Avoid using metal implements or anything sharp to scrape away the debris, as this can scratch and damage your timber further, which can lead to rotting

3. Clean and remove mould off your decking

If mould has begun to develop on your deck, a ready-to-use concentrated treatment is often the best (and simplest) solution to thoroughly clear up the problem and protect your deck boards from mould and algae regrowth in the future.

Mould is relatively easy to remove, but if left untreated can cause irreparable damage to your timber decking. Take the time to treat it when you see it. Be sure to treat mould before washing your deck to prevent spreading the spores around.

4. Wash the dirt away

A pressure washer can give your deck a thoroughly clean finish, but make sure to use a wide nozzle to evenly disperse the water flowto prevent damage to your boards.

Using smooth sweeping motions, pass the spray across your deck moving from one end to the other, going with the grain of the boards. Take great care not to position the nozzle too close to the boards to minimise the risk of damage.

Garden hoses can come in handy for cleaning your decking – if dirt hasn’t had a chance to stiffly adhere to the boards, a pressure washer may be too aggressive, and a hose can gently clear away leaves, debris, and twigs.

Once stubborn dirt has been removed, you may wish to use a deck cleaner or gentle soap solution on a stiff brush to complete the process.

Decking cleaning FAQs

Is it possible to clean your deck without a pressure washer?

Absolutely yes! If you don’t want to invest in or hire a high-pressure cleaning machine, you can resort to your good old garden hose and attach a nozzle sprayer to its end. To remove hard-to-clean marks and stains, as well as clean in between the decking boards, you can use a stiff brush or a broom.

Can you clean your decking with washing-up liquid?

Washing up liquid is fine to use on your deck. Just ensure your liquid is ammonia-free and you don’t use too much of it.

Can you clean decking and composite decking with bleach?

We do not recommend this approach to clean your decking. And harsh chemicals such as bleach should never be used on your composite decking.

How to treat your deck

If you want your decking to stand the test of time, you're going to need to treat it. We've pulled out the top tips you need to see your decking last the ages.

1. Timing your treatment

Brand new timber decking is best left alone until the wood’s original treatment has had a chance to break down over time. This will help any paint or stain to properly adhere to the timber’s surface, giving you a longer-lasting result. If you’re re-treating a deck, or your deck’s original treatment has worn away, you’re ready to apply your chosen treatment.

2. Check the weather before treating your deck

Decking treatments should ideally be applied in warm, dry weather. If you’ve had recent rain, make sure your boards have had a chance to dry thoroughly. Take care to avoid extremely hot conditions, however, as this may cause your treatment to dry too quickly before it’s fully absorbed.

3. Paint, stains, or oils for treating decking

It’s time to decide what you want from your decking treatment, and how you want your final deck to look. Each option has its benefits and drawbacks, so it’s important to properly research before you buy.

Using paint is great for a bold, eye-catching finish. Stains offer rich colour without losing the natural charm of your decking’s wood grain. Oils will typically enhance the wood, rather than masking it, protecting the finish, and waterproofing the timber.

4. Apply your treatment

Stir your chosen treatment thoroughly before application, this will help to ensure an even colour and consistency.

Using your tool of choice (brushes, rollers, and pads are all suitable depending on your deck and ability) apply your treatment generously, working along the length of the boards.

While a thorough coating is necessary, be careful not to overload your deck with the product, particularly in the case of oils.


5. Consider non-slip solutions

In preparation for cold, wet weather, you may consider using a non-slip treatment on your decking. While non-slip paints and varnishes work well in the short term, they tend to start flaking off before long. An anti-slip decking oil, on the other hand, will not crack or peel and is easy to replenish when needed.

These oils are usually natural and contain compressed particles to create a rougher, non-slip surface. This option can be a little pricey, especially if you have a very large decking area, but it’s a worthwhile investment if a non-slip deck is important to you, and you don’t want to change the appearance of your decking too much.

Decking treatment FAQs

Should you treat a new deck?

Yes, you can paint or stain new pressure-treated decking, but for a long-lasting and great-looking finish evaluate the wood's moisture content first, then use the correct wood decking paint and primer.

Should I treat composite decking differently from wood decking?

New composite decks do not require sealing. Composite decking is made from a blend of recycled plastics and wood fibre, which gives it the appearance of wood but makes it more durable 

Can you paint treated decking?

Yes, you can paint treated decking. The trick here is making sure that the treated timber is allowed to dry first.

A quick test will usually let you know whether your treated wood is ready to paint.

To test your decking, just dab a few drops of water onto your treated wood. If the water soaks into the wood pores, then the treated wood is dry enough to paint. However, if the water beads on the surface, you probably still need to wait a little longer.

How to stop decking from being slippery in winter

Slippery decking can pose a serious safety risk, particularly in winter when you add sub-zero temperatures, ice, and snow to the already-wet conditions. Knowing how to prevent and treat slippery decking surfaces can make all the difference as the adverse weather conditions begin to close in, so we’ve put together a list of five easy tips on how to stop decking from being slippery to help you prevent any nasty slips and falls this winter.

1. Keep on top of cleaning

Winter weather is typically wet, and wet timber is a breeding ground for slippery algae and fungus growth. It’s never more important to keep your deck clean than in winter. If there’s a build-up of leaves or fungus (large decks are particularly prone to collecting rotting leaves over the autumn months), take the time to remove this before the cold weather sets in.

2. Rubber grip mats

You can buy outdoor rubber grip matting as a quick and easy way to make decking non-slip. These mats are a great temporary solution to get you safely through the winter months and, though they’re not the prettiest of options, they’re ideal for the colder seasons when you’re spending less time in the garden.

Simply lay yourself a narrow walkway using the mats, which are designed to withstand all weather conditions, and then store them away for next year once the weather dries up again in the spring.

3. Proper snow and ice removal

When the weather gets really cold and the snow and ice set in, your decking can become a miniature ice rink overnight. Your first instinct might be to hack at the ice with a metal shovel or lay down grit salt to melt it all away, but these will not be openly welcomed by your timber decking.

The metal tools can damage and open up weak points in your decking, while the harsh chemicals in grit salt can also corrode your timber and metal hardware if left to sit for days. If you have lots of snow and ice build-up on your decking, try using a plastic shovel to remove as much as you can.

Then, if the rubber matting option doesn’t suit you, you CAN sprinkle a little grit salt onto your decking, as long as you remember to rinse it off as soon as the ice and snow have melted away. Note: if you have composite decking, grit salt is safe to use.

4. Non-slip decking

Easier said than done, we know, but it’s so worth it. Anti-slip decking is made with pre-treated timber that is resistant to fungal growth and insect attacks, and features built-in abrasive strip inserts that blend in with an attractive, natural look.

If you’d prefer not to install anti-slip deck boards across your whole deck, consider using them on particularly troublesome areas such as steps or exposed edges.

With the proper care and attention, you can expect your garden decking to last over 15 years (and up to 30!). Maintenance needn’t be arduous. Keep cleaning regular and treatments as required, and you’ll have a fantastic deck for years to come.

At Arnold Laver, we don’t just do timber. We’re here to help you with advice on all kinds of topics from flooring to cladding. Browse our blogs to find out more, or call us and chat with one of our friendly team for professional advice.

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