FAQs & Experts

Can interior sealers be used outside and can exterior sealers be used inside?

The interior sealers cannot be used outside. They do not provide protection against the sun as they do not contain any UV-absorbers. The exterior sealers can be used inside, but will take longer to dry than outside. It is recommended however, that interior sealers are used inside and exterior sealers outside.

Are the different interior sealers compatible, e.g. can Woodoc 20 be applied over Woodoc 10?

The different interior sealers are compatible and can be applied over each other, provided the surface is first cleaned/scrubbed well with steel wool and mineral turpentine.

Are the different exterior sealers compatible, e.g. can Woodoc 30 be applied over Woodoc 50?

The different exterior sealers are compatible and can be applied over each other, provided the surface is first cleaned/scrubbed well with steel wool and mineral turpentine.

Can interior sealers be applied over exterior sealers and exterior sealers over interior sealers?

This is not recommended, as the exterior products have been formulated with exterior conditions in mind and the interior products with interior conditions in mind.

Can Woodoc sealers be applied over other sealers/sanding sealers/varnishes/paints?

Because Woodoc Sealers are penetrating sealers, they must be applied to bare, sanded surfaces so that they can penetrate deeply to feed the wood, bind with the wood and finally form a protective coating on the surface. Woodoc sealers should therefore NOT be applied over other varnishes, sealers, paints or sanding sealers.

Can other paints/varnishes/sealers be applied over Woodoc products?

Most oil paints with mineral turpentine as solvent can be used over Woodoc products. The best is to consult manufacturers of other products to determine whether their products can be used over Woodoc products.

How to ensure that Woodoc 5 does not create a shiny/glossy finish?

Stir the tin very well before and also during application. Do not apply in direct sunlight. Finish off with fine steel wool and Woodoc Deep Penetrating Furniture Wax for a smooth “oiled” finish after the third coat of Woodoc 5 had dried.

How to ensure that Woodoc 10 does not create a shiny/glossy finish?

Sand lightly with fine steel wool and Woodoc Deep Penetrating Furniture Wax after the third coat had dried. This will create a lovely, smooth velvety finish.

Why does a wet glass leave watermarks, even though the surface had been sealed with a Woodoc interior sealer?

A water mark is an indication that not enough product was applied. The application of three liberal coats of sealer, according to the application instructions, will prevent water marks.

Why do the Woodoc interior sealers sometimes leave a patchy finish on wood types such as Imbuia and African Padauk?

These are oily wood types and difficult to finish. The wood should be scrubbed thoroughly with steel wool and mineral turpentine after sanding and before applying a Woodoc sealer. Wipe dry and apply. Do not wait for days before applying a sealer as the oil will exude again.

Why would Woodoc interior sealers peel off?

They could peel off if applied over old varnish or polish, or if there is oil in the wood, preventing penetration of the sealer. Damp wood could also cause the sealer to peel off as the moisture will prevent the sealer from penetrating into the wood.

Is Woodoc 25 a glossy product?

Woodoc 25 is available in two finishes:

• Satin – a glossy finish and
• Matt – a matt finish

Can Woodoc sealers be used on veneers?

Woodoc products were formulated for use on solid wood. There are therefore products that can not be used on veneer e.g. Woodoc 5 and Woodoc 10. Woodoc 20, Woodoc 25 (Matt & Satin), Woodoc 2000 can be used on new veneer.

Which wood types are suitable for the application of Deck Sealer?

Soft porous wood types, e.g. pine, meranti.

Which wood types are suitable for the application of Deck Dressing?

Hard dense wood types, e.g. balau, iroko, kari, teak, saligna.

What type of finish does the Deck Sealer provide?

A low-gloss finish.

Why a Deck Sealer when Woodoc 55 is also suitable for soft porous decking?

Consumers wanted a low-gloss finish for decks. If a customer prefers a high gloss product, he can still use Woodoc 55.

Surface preparation before applying the Deck Sealer?

The same as for any Woodoc Exterior Sealer.

Can the Deck Sealer be used on other surfaces, besides decks?

Woodoc Deck Sealer is also suitable for window frames, doors, gates, where a tinted, low-gloss finish is required.

What type of finish does the Woodoc Deck Dressing provide?

The finish will vary from matt to glossy, depending on application, product build-up, type of wood – it will look more matt on more porous wood types. It will give a glossier appearance on dense, oily wood types and will walk off and weather quicker.

Surface preparation before applying the Deck Dressing?

Remove/sand down any old sealer or varnish. It is very important that it be applied to an unsealed or bare surface. If the surface had been oiled/Woodoc Penetrating Weatherproof Wax had been used, scrub well with stiff brush and mineral turpentine.

Can the Deck Dressing be applied over old varnish/sealer which had only weathered partly or which had not been stripped off completely?

NO! If the Deck Dressing is applied over old sealer/varnish it will not be able to penetrate, it will cause drying problems and when the old sealer/varnish starts coming off, the Deck Dressing will also come off.

Is the Deck Dressing a sealer or an oil?

Neither. It can be placed between an oil and a sealer. It will last longer/work better than an oil, but not as long/as well as a sealer. Because it is not a sealer, it does not form a hard layer on the surface.

Will the Deck Dressing protect wood against moisture?

Yes.

When should the Deck Dressing be reapplied?

Once every 6 months, or when the wood looks dry. Porosity also plays a role. The more porous the wood is, the more often it will have to be applied.

What should be done before the Deck Dressing is re-applied?

Clean with a stiff brush and mineral turpentine before reapplication.

Drying time for Deck Dressing?

Up to 2 days per coat.

What about fungus and fungal growth?

The Deck Dressing contains a dry film fungicide. It will combat fungal growth and still be environmentally friendly. It is a fungicide, not an insecticide and has been approved by the EU (European Union). But:

• It is not a wood preservative.
• Deck Dressing should not be used on untreated wood, i.e. wood must be treated against insects first.
• Climatic conditions also play a role: in traditional humid areas, e.g. Durban, fungal growth could still be experienced occasionally.

Why does the Deck Dressing not get hard?

Because hard dense wood types expand more on a hot day than soft porous wood types, the Deck Dressing is “soft” in order to be more flexible and be able to move with the wood.

Can the Deck Dressing only be used on decks?

The Deck Dressing can also be used on window frames, doors, gates if made of hard dense wood types, but it will have to be done regularly. It should not be used on garden/patio furniture. Because the product does not form a hard layer, it could come off on cushions and clothes.

Can other Woodoc Sealers be applied over Deck Dressing?

Yes, but first clean the surface with a stiff brush and mineral turpentine.

Deck Sealer and Deck Dressing are available in the same colours, but do they look the same once applied to wood?

Although the products have the same pigment composition, it will not necessarily look the same on wood. The Deck Sealer forms a film, which will give better colour development, while the Deck Dressing does not form a film and therefore a different colour appearance will be formed.

Is it necessary to sand between coats?

A light sanding with fine steel wool is essential as it smoothes down the wood fibres which tend to stand up when the sealer is applied. If no sanding is done between coats, the end result will be a rough finish.

Why do the sealers thicken in the tins and how to prevent this from happening?

As the tin is opened and the sealer used, oxygen enters the tin and this causes the sealer to thicken eventually.

• Storing the tin upside down will help.
• Always close the lid in the same position by marking the tin and the lid with a koki pen.
• Do not use a hammer directly on the lid when closing, it damages the lid. Rather put a plank over the lid and hammer the plank.
• It is also a good idea to decant the remaining sealer into a smaller tin or a glass bottle with a long neck.
• Keeping the tin artificially full by adding marbles as the sealer is used, also helps to prevent the sealer from solidifying.

What to do when the sealer (mostly Woodoc 10) turns to jelly in the tin?

Although it is too late to dilute it, this “jelly” can still be applied with a cloth to create a lovely velvety finish.

What to do when the sealer remains sticky after application and does not dry completely?

Clean down well with steel wool and mineral turpentine, allow to dry and apply next coat. If it remains sticky, sand down to bare wood.

Why can the Woodoc sealer sometimes be scratched off the surface?

If the sealer can be scratched off the surface, it probably has not dried properly, in which case it should be left to dry. In cold weather the sealer will take longer to dry. There could however, be another reason: if there is any oil/wax/polish in the wood, it could be preventing the sealer from drying properly. Leave to dry, but if not dry within a day or so, scrub very well with steel wool and mineral turpentine. If the problem continues, sand down to bare wood.

Why does one litre of Woodoc Sealer/Penetrating Wax not weigh one kg?

This has to do with the density of Woodoc products. Water, which has a density of 1 g/ml, is used as a standard measure of density and one litre of water will weigh one kg. All the Woodoc sealers and waxes have a density of less than 1 g/ml and that is why one litre of Woodoc will not weigh one kg, but slightly less, depending on the densities of the raw materials used.

Can a Woodoc sealer be used over a spirits-based stain?

This can be done, provided that the wood is left for at least two weeks so that the stain can dry completely and the solvent can evaporate completely. Then only can the Woodoc sealer be applied.

Why do the clear sealers not look clear in the tin?

This is caused by the raw materials used in the sealers. The raw materials appear coloured, but the sealers will dry to a clear finish. To test, apply sealer to a clear glass panel and leave to dry.