Short answer: In our comparative test, after one year we could neither see nor feel any clear difference between decking treated with VästerbottensSåpa and decking treated with traditional decking oil.

There is a common belief that decking oil protects wood so effectively that the difference only becomes apparent after one or more years. To investigate this, we conducted a simple comparative test under real outdoor conditions.

 

 

How the test was conducted

We have a pressure-treated deck, a few years old, at the entrance to our offices, which we used as the test area.

The deck was divided into two equal sections.

• One half was treated with VästerbottensSåpa.
• The other half was treated with traditional decking oil according to the manufacturer’s instructions.

After treatment, the deck was left outdoors for approximately one year and exposed to normal Swedish weather, including sunlight, rain, temperature fluctuations and natural wear. No additional treatment was carried out during the test period.

After one year, the result was documented with photographs and video.

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The right side is oiled; the left side was scrubbed with soap.

After one year, it looks like this:

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Results after one year

When the deck was compared after approximately twelve months, we could not see any clear visual difference between the soapy-water-treated and oiled sections.

Nor could we detect any clear difference in the feel of the surfaces when touched.

In this test, there was therefore no measurable or obvious advantage to the oiled surface compared with the soap-scrubbed surface after one year of normal outdoor exposure.

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What does the test show?

The test shows that the claimed long-term effect of decking oil was not visible in this particular test after one year of use and exposure to the weather.

This does not mean that decking oil can never affect the properties or service life of wood. However, in this practical comparative test, we were unable to observe any clear difference between the treatments after one year.

It is therefore difficult to claim, based on our observations, that the oiled section was in better condition than the soap-scrubbed section.

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Limitations of the test

To provide a fair picture, it is important to describe the scope of the test.

This is a practical comparative field test, not an accredited laboratory test.

The test included:

• one small pressure-treated deck
• two different treatment methods
• approximately one year of outdoor exposure
• documentation with photographs and video
• visual and tactile assessment

We did not analyse the wood’s moisture content, strength, chemical changes or biological degradation.

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Frequently asked questions

Is a soap-scrubbed deck lighter than an oiled deck immediately after treatment?

Yes. Immediately after treatment, the oiled section became darker, while the soap-scrubbed section retained a lighter wood character.

Is the difference visible after one year?

In our test, we could not see any clear difference between the surfaces after approximately one year.

Did the surfaces feel different?

Not after one year of exposure. In our assessment, there was no clear difference in feel between the soap-scrubbed and oiled sections.

Does the test prove that decking oil has no effect?

No. The test only shows that no clear difference could be observed in this specific comparative test after one year of normal outdoor exposure.

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Conclusion

In this practical comparative test, two sections of the same pressure-treated deck were treated using different methods: VästerbottensSåpa and traditional decking oil, respectively. After approximately one year outdoors, we could neither see nor feel any clear difference between the surfaces. This means that the protective properties often attributed to decking oil were not visible under the conditions covered by the test.