Throughout our website and brochures, you may see a ‘Professional Product’ logo to reference certain products.

This icon indicates that this product is recommended only for professionals and/or users which are extremely familiar with Osmo products.

Professional labelled products require specialist knowledge, experience and/or tools to use these products optimally. This is due to either specific preparation methods, extra attention to detail in terms of application techniques, requires specific working times and/or drying times or requires more than one component to complete the project.

For product consultation and expert advice before choosing these specialist products, please contact the Osmo Advice team today or a member of staff in store.

New or Freshly Sanded Wood

Fresh wood containing natural wood ingredients/extractives, such as Cedar, Larch, Teak etc, are often less absorbent and require weathering before applying any Osmo Oils. Pressure treated soft wood will also require a period of weathering.

Weathering helps ingredient rich wood become more absorbent, and so an Osmo wood finish will adhere optimally.

Some wood species contain water-soluble coloured extractives which may leach out naturally and stain the treated surface. By pre-weathering these wood species it helps to reduce staining.

Weathering is also required if ingredient rich wood has been freshly sanded or renovated.

On every Osmo website product page, there is also a suitability tab to explain more.

Weathering Periods

Before the treatment of ingredient-rich and hardwood species, a weathering period is strongly recommended. Exposure to sun, wind, and rain during this time allows the wood’s natural ingredient-rich content to extract from the surface which is necessary for the oil to penetrate and provide maximised protection. Heavier rainfall can accelerate this process.

1. Cedar: approx. 12 weeks
2. Iroko: approx. 12 weeks
3. Mahogany: approx. 12 weeks
4. Teak: approx. 12 weeks
5. Walnut (tropical origin): approx. 12 weeks
6. Ipe: approx. 12 weeks
7. Merbau: approx. 12 weeks
8. Wenge: approx. 12 weeks
9. Rosewood: approx. 12 weeks
10. Sycamore: approx. 12 weeks
11. Pressure-Impregnated Pine: approx. 12 weeks
12. Larch: approx. 2-6 weeks, application of WR Base Coat is recommended before finishing.
13. Sapele: approx. 3-4 weeks
14. Oak: optional 6 months if reduced tannin content is desired

For all other ingredient-rich hardwood species not mentioned, please contact the Osmo Advice team for further information.

Not Recommended

1. Green Oak: moisture content is often above the maximum 20% RM recommended.
2. Idigbo: contains yellow dyes which leaches when the wood becomes wet and stains when in contact within iron.
3. Other: woods treated with a varnish, lacquer or other surface coatings must be completely sanded before use.

After Weathering

After the weathering period, the wood is unlikely to discolour. However, for optimal results we recommend restoring the wood’s natural colour and character with Osmo Wood Reviver Power Gel.

Simply wet the surface with water then brush apply generously along the grain. Wait approximately 20 minutes, then clean the surface with an Osmo Decking Cleaning Brush. Rinse well with water. Always protect sensitive surfaces like stone (e.g. limestone or marble) and metal (e.g. aluminium).

See recommendation for more product information and instructions.

After Wood Reviver

After the Wood Reviver Power Gel step, it is good practice to clean the surface using methylated spirit to remove remaining wood extractive residues.

Then, apply your chosen Osmo wood finish as recommended on its product page.

For all products, please always trial apply!

When signs of wear becomes visible, re-coating of the Osmo wood finish is highly recommended.

The following steps are recommended to achieve optimal results for your wood project, specifically cladding, decking, and other similar projects which when installed have non-visible, hidden wooden surfaces that also require protection. These steps will also help provide higher protection from residual moisture.

1. Preparation

Prior to installation and the weathering period, Osmo recommends to wipe all wooden surfaces which will not be visible after installation with either methylated spirits or Osmo Brush Cleaner and Thinner. Allow the cleaned surface to fully dry prior to treatment.

Please leave the wooden surfaces which will remain visible after installation untouched and ready for the weathering period.

Why? Cleaning with methylated spirits or Osmo Brush Cleaner and Thinner is needed to help de-grease some types of wood species, and facilitating the absorption of the Osmo product.

2. Product Application

Once the hidden surfaces have been wiped/prepped and allowed to fully dry. Depending on wood species, apply WR Base Coat 4001 to all hidden parts (e.g. back, sides and ends). Once fully dry, apply one thin coat of the chosen finish to the hidden parts and allow to dry. Finally, treat the end grain sections with two thin coats of Osmo End Grain Sealing Wax 5735 for added protection.

For this process, one coat of each product will be sufficient. However, for best results, WR Base Coat and End Grain Sealing Wax can be applied twice.

3. Installation

Once the final Osmo product is dry, you may complete the installation of your project leaving the untouched, visible wooden surface exposed for weathering.

4. Weathering and Application

Now that your project has been fully installed, please follow Osmo Recommends App from Step 1: weathering onwards.

Weathering will improve the absorbency of the wood ready for treatment with Osmo.

After the weathering period, Osmo recommends using Wood Reviver Power Gel to help clean and de-grey weathered wood. Please protect sensitive surfaces (e.g. Stone and Aluminium) whilst cleaning. Once all surfaces are rinsed and dry, apply the recommended Osmo products for optimal protection followed by the recommended Osmo finishing products.

Note: If you require ‘a finish that allows the wood to naturally grey over time’ Wood Reviver Power Gel will not be required.

Expert Advice

The information above relates highly to wood cladding and decking projects, however you may have a project with similar hidden surfaces that you need consultation on.

For expert advice on any project, pre- and post-installation, please contact the Osmo Advice team today.

We’re always here to help!