Using Napisan to Clean a Deck (How To Guide)

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Keeping a timber deck clean is important for its appearance and durability. Decking can start to look worn and faded after just a few months but cleaning it with the right product can restore the finish and bring it back to life.

Before you go out and buy an expensive deck cleaner, check your cupboard for Napisan. This step by step guide will help you clean your deck with just a few basic pieces of equipment, water and Napisan.

Why Use Napisan?

To clean a deck you don’t need any fancy cleaning detergents with big names and big price tags. You may have heard that Napisan is a suitable option for cleaning timber decking and it’s true, it is a great choice for cleaning decking.

Napisan contains sodium percarbonate which is the active ingredient found in most deck cleaner products. This is what makes Napisan an effective outdoor decking cleaner without needing to use a decking-specific product.

The sodium percarbonate helps to get rid of the mould, mildew and algae that are often found on timber decking. Removing this helps improve the colour of the wood and also helps prevent the surface from becoming slippy in wet weather. It is also effective in removing residue left from UV degradation.

When diluted and used on timber, Napisan acts as a cleaning and stain remover. It also prepares the deck ready for oil treatment. Once the oil has been applied to protect the deck it restores the decking to its natural appearance. It’s common for the deck to look quite bare after a thorough clean and the oil treatment is necessary to restore it to its former glory.

How To Use Napisan To Clean a Deck (Step by Step)

What You Will Need:

  • Bucket for Napisan mixture
  • Napisan mixture (the ratio for the Napisan mixture is 2 cups with 10 litres of hot water. Mix well until the Napisan dissolves)
  • Mop
  • A sturdy broom
  • Hose for rinsing

Step 1:

Take the Napisan solution and mop the decking boards. Don’t over-mop as this will saturate the timber and cause problems. After you have mopped once, leave the decking for around 15 minutes. The decking shouldn’t look wet but it should look damp. The deck shouldn’t dry during this time (it’s best to clean the deck when the sun isn’t on it but if the sun does start to dry the deck then lightly spray it with water or add some more cleaner)

Step 2:

Now you can take the brush, submerge it in the Napisan solution and begin to scrub the wood. The brush needs to be tough but it shouldn’t scratch the decking boards. Cleaning the deck with the brush is going to take some time but it will remove any stains as well as tougher dirt and blemishes.

Step 3:

Once you have given the deck a good scrub with the broom you can hose it off. Rinse the surface off thoroughly using a hose. Once all of the solution has been removed, leave the decking to dry for a few days. It should be left for at least a full 24 hours. The decking is now clean but will probably need oiling now the dirt and old oil residue has been removed.

Depending on how your decking looks you can now sand back the surface if needed and apply a new coat of decking oil. You will only need to sand the surface if there are areas of old water-based coating.

You will also need to sand the deck if you are switching from a water-based coating to an oil base.

How To Apply Decking Oil

Now that the wood is dry and clean it is ready for you to apply a new coat of decking oil. You will need:

  • The colour oil of your choice
  • A decking brush
  • A mixer (a stick to stir the oil)
  • An applicator/ pole
  • A paint tray
  • A rag to clean up

Before you begin to apply the oil to the timber give it a good stir with the mixer to make sure the colour pigment is all mixed in properly. Now you can make a start, apply the colour stain equally to each board. For best results, use long stroked to coat the wood in oil. Apply the deck oil to the entire length of the board before moving onto the next board along.

Only use as much oil as the timber deck will absorb. If you’re not sure how much to use, you can apply the oil and then wait for 5-10 minutes to see if it all absorbs. If it is too much you will need to remove the excess and if it is too light you can use more oil as you continue with the deck.

Let it sit for the amount of time specified on the oil instructions and add a second coat when ready. When you apply the second coat, use less than you did the first time as it won’t be absorbed as easily the second time. If you use too much the oil will sit on the top and attract dust.

Applying oil to the timber decking may take some time but it is worth it for the added outdoor protection. The timber decking will be able to withstand wet weather as the oil will provide rain protection as well as a great colour stain too.

Deck Cleaning Summary

As you can see, cleaning a timber deck with Napisan is very straightforward. Using the Napisan and water mix creates an easily accessible, low-cost deck cleaner that can wash away even tough stains and bring your deck back to life. You’ll need to put in a little bit of elbow grease, but this is always going to be the case even when using expensive deck cleaners. Remember to leave the mix on the deck for around 15 minutes as this helps to loosen it up.




This article was written by Jim Marsden

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