Wooden deck maintenance: cleaning, sanding and oiling

The Danish weather is hard on a wooden deck. Without protection from rain, sun and frost, the wood quickly turns grey, slippery and worn. The good news is that a wooden deck can last for many years if you look after it. Here is a simple step-by-step guide to cleaning, sanding and oiling the wood so it looks good again.

How often should a wooden deck be maintained?

A thorough treatment once a year is usually enough. Most decks benefit from a thorough clean in spring and oiling in spring or early summer, when the wood dries quickly. If the deck is very exposed to sun and rain, it may need oil twice a year.

Step 1: Thorough cleaning

A thorough clean removes dirt, algae and the grey layer that has formed on the surface.

• Use a bucket of lukewarm water and a wood cleaner suitable for outdoor use.
• Scrub the wood thoroughly with a brush, sponge, or mop.
• Rinse with a garden hose, not a pressure washer. Too much pressure raises the wood fibres and causes unnecessary wear to the boards.
• Let the wood dry completely. How long it takes depends on the sun and weather.

Drying time is important. Damp wood should not be sanded or oiled, as this will trap moisture inside.

If there is green algae and lichen deep in the wood or on the tiles next to it, you can read more in our guide on how to remove lichen.

Step 2: Sanding

Sanding removes splinters and the grey, weathered layer and prepares the surface for treatment.

• For a light refresh, you can use a sanding sponge on a telescopic pole.
• For a more even, refreshed appearance, use a random orbital sander or another electric sanding tool.

If the wood is very worn or has turned silver-grey throughout, machine sanding is the best option. This is where it makes sense to get professional help if you want an even result without having to handle the machinery yourself.

Step 3: Oiling

Oiling protects the wood from the weather and brings out its natural grain.

• Choose a good wood oil, for example Gori 303.
• Use an Anza deck kit to apply the oil.
• Apply the oil in an even layer, let it soak for 10-15 minutes, and wipe off any excess.
• Repeat if the wood is not saturated.

Use a brush for corners and hard-to-reach areas. Apply masking tape where you want a clean edge.

Protective treatment

To keep the wood looking good for longer, you can apply a penetrating protective treatment after sanding and before oiling. It makes it harder for moisture and algae to take hold in the wood, which means less work for you in the coming seasons.

How to make your deck last longer

Even if the wood has been treated, it requires ongoing maintenance. We recommend oiling once or twice a year, depending on how exposed the deck is to sun, rain, and wear. Sweep away leaves and dirt regularly, and keep an eye on whether water can drain away so the boards don't stay wet.

If you want to avoid keeping track of it yourself, you can sign up for our oiling plan and have your deck oiled automatically once or twice a year.

When should you get professional help?

You can take care of routine maintenance yourself. But it makes sense to get professional help when the wood is very worn or silver-grey and needs machine sanding, when the deck is large, or when you want an attractive, lasting result without doing the work yourself. We sand, clean and oil balconies and decks throughout Denmark, and you will receive a non-binding quote with a fixed price before we start.

Frequently asked questions

How often should a wooden deck be oiled?

Most decks benefit from oiling once a year. If the deck is very exposed to sun and rain, it may need oil twice a year.

Should a wooden deck be sanded before oiling?

Yes, if the wood is grey, rough or splintered. Sanding removes the weathered layer so the oil can penetrate and protect the wood. If the wood is still in good condition, a thorough clean may be enough before oiling.

Can you use a pressure washer on a wooden deck?

It is best to avoid it. High pressure raises the wood fibres and wears down the boards. Use a garden hose and a stiff brush to clean the wood instead.

What is the difference between a penetrating protective treatment and oiling?

A penetrating protective treatment makes it harder for moisture and algae to take hold in the wood. Oiling provides a protective, nourishing surface treatment and brings out the wood's grain. The two work well together.

Can you maintain my deck for me?

Yes. We sand, clean and oil balconies and decks throughout Denmark. You will receive a fixed-price, no-obligation quote before we start, and you can sign up for our oiling plan if you would like us to take care of it each year.