How to clean decking – whether it’s wood or composite

Find out how to clean decking – remove dirt, algae, and mold from all decking materials in a few easy steps

A small decked backyard with wooden furniture
(Image credit: Kristin Mitchell / Getty)

Learning how to clean decking is actually very easy. Whether your deck has suffered from a wet winter and is growing algae, or it just needs a bit of TLC before staining or painting, this failsafe method for cleaning decking will work on decks of all types and ages.

And if you got your eye on a few winning deck ideas, then you will definitely need to get your deck clean to really set the finished look off.

So, wait for a dry day and get to it. Of course, if you own one of the best pressure washers, the job has just become a whole lot easier. But even if you don't, you can still restore your deck to its original, stain-free look.

You will need

1. A pressure washer: choose one of the best
2. White or distilled vinegar: bulk buy for cleaning
3. Cleaning gloves
4. A decking cleaner: We like these decking cleaners
5. A scraper: the Mojack deck scraper works wonders
6. Baking soda: buy a large pack on Amazon

7. Detergent: A mild wood detergent or dish soap

8. A stiff broom: Grab one on Amazon

9. A scrubbing brush: The Vikan hand brush is ideal

How to clean a deck

1. Clear the deck

Before you get to the deck cleaning, a little deck clearing is in order. If you left any furniture out on the deck over winter, move it out of the way. Then move any pots or planters away from its surface, too. To protect plants and grass nearby, you’ll need to cover them.

2. Brush away debris

Next, brush the surface of the deck using a stiff broom. This will get rid of any debris, but it will also help you make a start on growths like moss and mold. If you have decking with grooves, always make sure you brush in the direction of the grooves to get out the dirt and debris that gets lodged in them. 

You can use a scraper to remove any grot that evades the bristles of the broom, but work with caution so you’re removing dirt not scraping the decking itself.  

3. Wash the deck with soapy water

Now, make a dish soap solution in a bucket. Apply it to the surface, and use a stiff scrubbing brush (shop a selection of stiff brushes on Amazon) to clean the decking. Rinse with clean water.

4. Use a decking cleaner for tough stains and mold

If you've got mold on your deck, or the soapy water method hasn't removed the algae stains, you'll need to go in with one of the best decking cleaners

Typically, these are applied with a brush or sprayed on, depending on the exact product you are using, and then left on the deck for a period of time between several hours and a couple of days. Bear this in mind when choosing when you clean your deck – you'll need a spell of dry weather for the cleaner to work. 

Some decking cleaners these days are no-rinse, so you don't need to do anything once you've applied them. Other products will need to be washed off after a while. Always read the instructions on the packaging.

A deck being cleaned with a pressure washer

(Image credit: Wojciech Kozielczyk / Getty)

5. Use the pressure washer

Generally, you’ll find that deck cleaning with soapy water or a commercial product will get the results you want. If it doesn’t, then you could use a pressure washer if you have one.  

The key is to keep the pressure to the lowest setting. Make sure you also stand back from the deck so the spray nozzle isn’t too close – about 2 feet (60cm) is a good starting point but you can reduce this if you need to. Don’t go nearer than 6 inches (15cm) to avoid damaging the boards. It’s easiest to test in an inconspicuous place first, then you can work at an even distance over the entire surface.

Make sure you work along the wood grain and section by section evenly and systematically to clean a deck. 

Bear in mind that you can get a decking-cleaning attachment for a pressure washer to help you keep the deck in good condition. 

Can you clean a deck without power washing?

It’s definitely not compulsory to own a pressure washer to clean a deck. We’d always recommend trying dish soap or a specialist deck cleaner before you embark on power washing. After all, you can still make your life easy by using your garden hose to do the rinsing.

Bear in mind that if your deck is made of wood, what might actually be required after cleaning to make it look good as new again is painting or staining the wood. If that’s the case, allow the deck to dry for 24 hours or more before application of the decking paint or decking stain. You can find more about how to stain a deck in our guide.

Garden furniture on a deck next to a garden pond

(Image credit: Nadanka / Getty)

How to clean decking naturally

Like the idea of cleaning decking naturally? The best homemade deck cleaner is warm water. OK, that’s not actually homemade, but it’s definitely an eco-friendly way to clean a deck, so if you’re a fan of natural cleaning do try this first.

The other natural deck cleaning option can be made with store cupboard favorites vinegar and baking soda (you can buy a large pack on Amazon). Use half a cup of white vinegar, a quarter cup of baking soda, and one gallon (3.8ltr) of water to make up the cleaning solution.

Is vinegar safe to use on decking? 

Vinegar is generally safe to use on decking, but only if it's appropriately diluted, and not too often. You can bulk buy vinegar for cleaning on Amazon. Cleaning expert Tricia Holderman advises using vinegar for decks that are seriously dirty and/or stained, not for regular cleaning: vinegar 'is more acidic and kills mold and/or algae better', she says. 

To clean your deck safely with vinegar, Holdremand recommends using '50 percent water, 50 percent white vinegar. Apply solution evenly on the patio, use a scrub brush to agitate thicker molds and algae areas, rinse with water.'

How to clean composite decking

Composite decking is really easy to look after and a dish soap solution could be all you need to keep it looking as good as when it was first laid. Just make sure you rinse your cleaning solution off completely once you’ve applied it and brushed the deck.

If your composite deck has developed any mold, you can use a vinegar and baking soda solution to clean it (see above).

Prefer the idea of using a commercial deck cleaning product? Make sure you only opt for one that’s designed for composite decking.

How to clean painted decking

If your deck is made from wood and painted, you can clean it using a dish soap solution, or a gentle deck cleaning product that won’t cause damage to the painted surface and expose the wood below. 

Check the label to make sure the cleaner is recommended for painted surfaces. If all else fails and you think your deck needs a real refresh, you can learn how to paint decking like a pro with our easy guide.

Sarah Warwick
Freelance Editor

Sarah is a freelance journalist and editor writing for websites, national newspapers, and magazines. She’s spent most of her journalistic career specialising in homes – long enough to see fridges become smart, decorating fashions embrace both minimalism and maximalism, and interiors that blur the indoor/outdoor link become a must-have. She loves testing the latest home appliances, revealing the trends in furnishings and fittings for every room, and investigating the benefits, costs and practicalities of home improvement. It's no big surprise that she likes to put what she writes about into practice, and is a serial house revamper. For, Sarah reviews coffee machines and vacuum cleaners, taking them through their paces at home to give us an honest, real life review and comparison of every model.