Frequently Asked Questions


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How should I prepare the surface of my wooden floor?

For the best result, the timber should be sanded - ideally by a professional floor sander with the right equipment. The sanding should follow the grain of the wood, and the end result should be without any sanding marks.

Timbers all have different hardness, and the sanding process should reflect this. For really dense, heavy hardwoods such as jarrah and ironbark, and oily / resinous timber such as matai, spotted gum and heart rimu, the timber should be finished at 100 - 120 grit sandpaper. For medium density timbers such as oak, tawa, rimu and macrocarpa, the timber should be finished at 120 grit. For softwoods such as pine, kauri and cedar, the timber can be finished at 150 grit.

Care should be taken to remove all scratch marks. Do not over sand the timber, as this may cause drying issues. Do not use worn sanding belts or discs as the grit will have worn off, and you will end up polishing the timber rather than sanding.


Are Osmo products certified?

Osmo products are in accordance with, and certified to, relevant European VOC-regulations as per DIN EN ISO 9001:2000 (Quality management systems) and 14001 (environmental management systems). These demonstrate that Osmo, as a responsible manufacturer of wood and wood finishes, is committed to developing itself and it's products to meet both the ecological and economic challenges which are faced in modern times. Due to the low amounts of solvents used in Osmo products, the Osmo production facility has not been bound by the German emissions law since 1998, in addition to these technical systems are also encapsulated to ensure that very little emissions can enter the atmosphere.

In New Zealand, the ingredients in Osmo products meet the requirements of the HSNO Act as relates to hazardous substances.


Where are Osmo products made and how?

Osmo has 2 locations in Germany. The main office is located in Warendorf, and the production takes place in Münster. They are about 25km apart. Osmo products are distributed by more than 2500 specialist dealers in Germany and in 65 countries around the world.

Osmo wood finishes have been manufactured for over 40 years in Germany. The ingredients are produced from purified and refined natural resources such as sunflower oil, carnuba and candelilla waxes, linseed, soya and thistle oils. The inorganic pigments used for Osmo Color are created from natural mineral ores. These are cleaned and refined until a level of physiological purity has been achieved and only a pure mineral element remains.

Osmo has been working for many years with "High Solid Products" which contain only a small amount of solvent. The solvent used in all Osmo products is classified as an "aliphatic hydrocarbon" which is a low odour mineral spirit. It is a pharmaceutical grade product.

The dry finish fulfills both the DIN EN 71.3 (suitable for children's toys) and DIN 53160 (fast to perspiration and saliva) certification, and as such is safe for humans, animals and plants.


Can I stain my wooden floor?

Yes. There are several strengths of coloured stains. Polyx Oil Tints contain a small amount of colour, resulting in a "washed" effect which evens out the variations in a timber's grain. Normally one coat is applied followed by one coat of clear Polyx Oil as the top coat.

For a deeper colour, we recommend using one coat of Osmo's penetrating Oil Stain followed by two coats of clear Polyx Oil.

Some timbers available in NZ do not handle coloured stains well. These include matai, some heart rimu, totara and spotted gum to name a few.

As with all Osmo products, we recommend purchasing a sample sachet of the colour(s) you like and testing for suitability on your own timber.


What product should I use on the inside of my sauna?

Osmo Germany's recommendation is that internal sauna timbers do not require coating, and should be left untreated. With 140 years of experience, and based in an area of Europe in which saunas are very common, we agree with their recommendation.

If for some reason, it is absolutely critical to coat the internal timbers, the only suggestion is to use 1 thin coat of Woodwax Clear 3101 applied by microfibre roller

Preparation should be initially heating the sauna to maximum temperature for 1-2 hours to completely dry the timber.

Allow the timber to completely cool again before applying one thin coat of the Woodwax 3101. Do not use any other Osmo product.

Ventilate the sauna for a period of 3-4 weeks before using it for the first time to exhaust any smell


What happens if Polyx Oil is over applied?

Polyx Oil is generally a 2 coat system. Each coat should be applied very thinly with the timber's grain. The second coat should not be applied until the first coat is dry (usually 8-12 hours).

Over application will result in too much oil at the surface. This will extend the drying time, and can result in water marking and scratching. Over application can occur when the wrong roller sleeve is used for application. The sleeve must be a low nap (3-5 mm) microfibre roller. Rollers such as foam, wool or mohair hold too much product, and this can cause over application.

Remember: less is best. A 2.5 litre can of Polyx Oil will cover approximately 60 square metres with one coat or 30 square metres with 2 coats.

If over application has occured, contact your flooring contractor to rectify the situation. If you have applied the product yourself, please contact the office during business hours for remedial advice.


What happens if Polyx Oil is under applied?

Osmo Polyx Oil is a 2 coat application. In some cases 3 thin coats may be needed on very soft timbers such as pine and cedar etc. If you have applied too little product, the floor may watermark, and the timber may dry out giving a dull and patchy appearance. In such cases, please apply another thin coat of Polyx Oil.


How long does the surface take to dry?

Osmo products usually dry in 8-12 hours under normal climatic conditions, but this depends on the timber. Oilt and resinous timbers such as matai can take several days to dry to the touch.

Very high or low temperatures or high humidity can also extend the drying time. Osmo Polyx Oil should not be used where the temperature is below 8 degrees C.

Osmo Polyx Oil Rapid will normally dry in 4-6 hours, and it the better option to use in cold conditions.

The surface dries by absorption and oxidation (air movement). Please ensure there is plenty of ventilation during the drying process. Do not use air conditioning or heat pumps to ventilate the area.


When can I walk on the floor?

As a general rule, the floor can be used 24-48 hours after the final coat is applied. However, you must first ensure the final coat is dry to the touch. Timbers such as matai, heart rimu, totara and spotted gum etc may take 4-5 days or longer to become touch dry.

The surface will take 14-21 days to fully cure. During that time we recommend the floor be treated with respect. This includes not using rugs or mats, not dragging furniture over the surface, and not wearing sweaty sock while walking on the surface, as these can contain oil and sweat which can stain the surface.

Also, if possible, keep dogs and cats off the floor, as their claws will scratch the surface.

If you must put furniture back, it should be lifted into position, and felt or similar should be placed under the contact points.


Can Osmo colours be mixed together?

Yes. The same products can be mixed together in whatever ratio you require, to achieve a larger colour range.

Only the same products should be mixed together. For example, Woodwax colours can be mixed together. Likewise, oil stain colours can be mixed together, however you should never mix oils stains with Woodwax.


What happens if I damage the Osmo finish on my floor, bench top or furniture?

Most traditional lacquers, varnishes and polyurethanes require sanding back to bare timber when damaged or needing a recoat. Osmo Polyx Oil is a hardwax oil and and damage in the finish can be repaired locally without the need to sand back to bare timber in most cases.

Most scratches may be removed by light sand, followed by the application of a thin coat of the product originally used.

Heavy scratching which has damaged the finish as well as the timber will need a more intensive repair, and may be best undertaken by a tradesperson.


Why do some of the Osmo product labels say the finish is "satin" and some say "satin-matt"?

Osmo initially used the terminology ‘Satin-matt’ for the labelling of products with English labels with a Satin finish. This is because the products are developed in Germany and is the result of a direct German to English translation of the term 'Seidenmatt'.

It was found that this caused confusion and from 2015 onwards, all Satin finishes are labelled 'Satin'.

Any Osmo can which refers to the finish as ‘Satin-matt’ is an older can label, but the can contains the exact same finish as the current label 'Satin'.

Osmo products will always be universally identified by the product code (e.g. 3032 or 420) as can labels may change from time to time.


Are Osmo products fire resistant?

Osmo products have been tested by BRANZ and have achieved a Group 3 rating (internal finishes) for Osmo Polyx Oil, which meets the requirements of the NZ Building Code relating to "Spread of Flame".


Do exterior transparent finishes offer UV protection?

Osmo's clear UV 410 and 420 offer a degree of UV protection. However, due to the strength of the UV in New Zealand, a clear finish will have a maximum lifespan of 6 months - or less in exposed conditions. (In Europe, these 2 products can last 5 years or longer as their UV is not as extreme).

Generally speaking, the more pigment (colour) the product contains, the longer the finish will last. Transparent finishes allow the timber's grain to remain visible. Light colours such as Woodstain White 900 and Woodstain Pearl Grey 906 only contain small amounts of pigment, and have a limited life. They are only recommended for use in areas which are not exposed to the weather.

A top coat with Osmo UV-Protection-Oil 420 can extend the life of other Osmo transparent finishes such as Natural Oil Woodstain.

In all cases, we recommend purchasing sample sachets and test the products on your timber.


What is the difference between the 2 clear UV oils 410 and 420?

The clear exterior UV oils 410 and 420 have different purposes.

UV 410 contains no biocides, and can be used in areas where food may be present - such as timber outdoor tables and furniture etc. The finish is a low satin sheen.

UV 420 "Extra" contains biocides as an extra ingredient to help fight fungal and insect attack on exterior timbers. It should not be used in areas where food may be present. It is recommended for use on timber pergolas, joinery and soffits. The finish is a high satin sheen.


I have half a can of oil left. How can I stop it from going hard in the can?

Osmo products dry by oxidation (contact with air). To help stop any remaining oil in the can from going hard, a piece of cling film can be placed inside the can down on top of the oil. This should stop any air in the can from coming in contact with the oil.