Practical questions about deck soap

How much deck soap is used, smell, slipperiness and the difference between regular soap and deck soap

It is often the practical questions that determine whether you actually get started. Here you will get clear answers to four of the most common concerns, with simple guidelines that work for most trolleys.

If you want the entire method from start to finish, you can find it here: How to scrub decking - step by step .

How much decking soap is used per square meter?

It depends on whether you are doing a cleaning or a main treatment, and how dirty the decking is.

Basic cleaning

For basic cleaning, use a weaker mixture (e.g. about 1 dl soap to 10 liters of warm water). Then the amount of water is the large volume, and the soap lasts a long time.

As a guideline, 10 liters of ready-mixed solution is usually enough for approximately 20-40 m² at normal dirt levels, depending on how generously you work and which brush you use.

In practice, this means that 1 dl of soap is often enough for a normal balcony when you are just doing a regular spring wash.

Deeper cleaning

If the deck is very dirty, you can increase to about 2 dl of soap per 10 liters of water. The mixture is enough for about the same area, but provides a more powerful cleaning where the dirt is more stubborn.

Expect to need a little more solution per square meter if the decking is rough, dry or has algae growth, as the wood absorbs more.

Main treatment

The main treatment is the saturated mixture (1 liter of soap to 10 liters of cold water) and is applied liberally without rinsing. This uses more soap, as the aim is to leave fatty acids on the surface.

As a guideline, it is reasonable to expect that 1 liter of soap is enough for approximately 20-30 m² for main treatment, depending on the decking's absorption capacity and how generously you apply.

An older, dry and slightly thirsty deck draws more. A dense and well-maintained deck draws less.

If you want to avoid guessing from year to year, we have put together a simple rhythm for spring, summer and fall here: How often should you soap your deck? A simple annual plan .

Does it smell like soap? And how long does the scent last?

Yes, soap smells. But not perfume or chemical, but more like clean and fresh with a mild note of classic soap.

How long the scent lasts depends mostly on the weather:

  • In the sun and wind, the scent may be gone the same day or within 24 hours.
  • In humid weather it can remain for 1-3 days.
  • During head treatments, where the mixture is allowed to dry, a faint scent may linger for a little longer, but it usually becomes discreet quickly.

Most people experience the scent as positive and freshly washed, not as something that bothers.

Does the deck get slippery when it rains?

A common concern, but in practice the answer is:

A soaped decking does not normally become slippery when dry. When it rains, all surfaces become more slippery, regardless of whether they are soaped or not. The main factors that determine the risk of slipping are:

  • Algal growth
  • Dirt film
  • Slope and standing water

Soap can actually help in the long run because the surface becomes easier to keep clean and less likely to develop a film of dirt where algae can attach.

A good tip for slip safety is to keep the decking free of algae and leaves, especially in shady areas. This makes a bigger difference than the choice of treatment.

Slipperiness is often associated with algae growth and dirt film. Here we have collected the most common mistakes when caring for decking and how to avoid them: Common mistakes when caring for decking .

The difference between regular soap and bar soap

Not all soaps are created for the same job.

Regular soap

Regular soap can certainly clean, but is often intended for household surfaces, floors, or general cleaning.

Deck soap

Decking soap is designed for outdoor wood and focuses on both effective cleaning and re-greasing, which helps the wood maintain its fullness over time.

How much time does deck maintenance take in practice?

Another common question is how much time it actually takes to soap a deck.

We have broken down the time required step by step here: How long does it take to soap a deck?

If you want to see how the method works on more surfaces, the guide is here: Can you soap balcony railings, stairs and outdoor furniture?