Frequently asked questions

To ensure a long service life, the wood must first be protected with a suitable wood preservative primer containing active ingredients to protect the wood against wood pests. The primer penetrates deep into the wood and protects it from biological pests (fungi that cause rotting or decay, insects or “woodworms”, bacteria, mould, etc.). The surface can then be coated with a surface coating such as Silvanol stain B wood paint, which further prevents elution and direct contact with biocidal substances. The surface coating also protects the wood from weather influences and enhances its beauty. Thus, we usually speak of a systemic protection consisting of a product or processes to protect the wood against pests (primary protection) and a final decorative coating (surface protection). Silvaprodukt offers several systemic solutions, depending on the application and the final appearance. The water-based systemic protection includes Silvaroyal® + Silvanol stain B for outdoor wood protection, Silvanol + Silvanol stain B for indoor protection and Silvanol + Silvacera® wax for protection of indoor wooden elements. A special section of the wood protection primer is Silvapro® thermally modified wood, which can be used alone, with additional systemic protection with Silvacera® wax, or with additional systemic protection with Silvanol stain B. The thermally modified wood can be used in all versions, both outdoors and indoors. However, it is also important to remember that products from different manufacturers for the same purpose can vary considerably. Combining one manufacturer’s primer with another’s surface coating can cause problems due to incompatibility.

Silvaroyal® is a highly effective biocidal product designed to protect wood used outdoors. The formulation of the product allows all the essential ingredients to bind extremely well to the wood and not to leach out of it, so that it can provide high-quality protection even for wood that will be exposed to the harshest conditions and weather (rain, snow, constant contact with soil, fresh or seawater). The shade of the wood after using Silvaroyal® is a mild pastel green. It is also available in brown as Silvaroyal® Brown.

For wood exposed to high humidity or insect infestation, but not directly exposed to precipitation, Silvanol is available two shades, colourless and yellow. It is used to protect wood indoors and also to protect roof structures, canopies, pergolas and facades when they are not directly exposed to precipitation.

After the primer protection with Silvaroyal® or Silvanol, the wood can be additionally coated and protected with Silvanol stain B.

If the roof construction is well protected from precipitation by a large eave, Silvanol can be used as a primer. If part of the roof construction is exposed to precipitation, Silvaroyal® should be used to protect it.

It is recommended that the wood is properly dried (wood moisture content between 15 and 25%) before applying the Silvanol and Silvaroyal® primers, but more important than the moisture content of the wood is the actual amount of preservative applied to the wood (which of course also depends on the moisture content of the wood), which should be a minimum of 250 g/m2 of the wood surface.

To protect wood that will be in constant contact with soil or water, Silvaroyal® primary protection must be used, and a suitable intake of the preservative for wood in contact with the soil can only be achieved by vacuum-pressure impregnation. For slightly less stressed wooden elements (such as facades or terraces), the process of dipping the wood in Silvaroyal® for 24 hours can also be used. Silvaprodukt offers both of these procedures in-house, as well as wood-dipping in several different locations around Slovenia. For more detailed information and instructions, please contact us at info@silvaprodukt.si or via the phone number listed under the contact tab. We will be happy to advise you.

If the raised bed will be in constant contact with the soil, high-quality protection is only possible by using a deep vacuum-pressure impregnation process with Silvaroyal®. At Silvaprodukt, we offer both 24-hour dipping and vacuum pressure impregnation services; the dipping procedure is also available at several different locations around Slovenia. For more detailed information and instructions, please contact us at info@silvaprodukt.si or via the phone number listed under the contact tab. We will be happy to advise you.

However, if the raised bed is protected from soil with a suitable foil (we recommend using a studded foil around the inside of the raised bed, with the convex parts of the studs pointing towards the wood), then coating, pouring or short-term dipping with Silvaroyal® wood preservative will also be sufficient to protect the wood.

If the fence is exposed to precipitation, protection with Silvanol is not recommended. In such a case, the appropriate quality of protection will only be achieved by using Silvaroyal® or Silvaroyal® Brown. To correct the shade, we recommend additional surface and decorative protection with Silvanol stain B.

If you still wish to maintain the initial light appearance of the wood, then the colourless Silvanol in combination with Silvanol stain B can of course also be used, but frequent recoatings will be necessary to maintain the light appearance of the wood, and the lifetime of such wood will be shorter than if the wood had been treated with the Silvaroyal® wood preservative primer.

The wood must be properly dried and cleaned, and then the penetration of Silvaroyal® should be maximised by coating, pouring or dipping. However, it is important to bear in mind that wood that has already started to rot will not gain mechanical strength from the impregnation process. For the protection of covered outdoor wooden elements, we recommend an additional surface protection with Silvanol stain B. For more detailed information and instructions, please contact us at info@silvaprodukt.si or via the phone number listed under the contact tab. We will be happy to advise you.

Scraping sounds in the roof elements are usually caused by insect larvae. The wood will therefore need to be impregnated with Silvanol if the entire roof construction is shielded from precipitation, or with Silvaroyal®, if part of the roof construction is exposed to precipitation. It is a good idea to maximise the penetration depth of the protective impregnating agent by coating and pouring. This prevents new insect invasions, while those that are already present in the wood will reach sexual maturity and then leave, and new insects will no longer be able to invade thanks to the protection of the wood. It is also advisable to coat the exit holes of insects so that they are not reused by other insects. If your roof construction is more intensively infested (a large number of insect exit holes), please consult our experts who will advise you according to your specific situation, we are at your disposal at info@silvaprodukt.si or call us on the phone number listed in the contact tab.

Approximately 40-50 kg of Silvaroyal® is needed to protect 200 m2 of roof (the recommended application rate of Silvaroyal® for roof constructions and other covered elements is 200-250 g/m2 of wood surface). The protective agent can be applied by coating, pouring or dipping. The effectiveness of the protection depends on the depth of penetration and the amount of protectant applied, which is higher for longer dipping in the protective agent or multiple applications in succession.

Approximately 4-6 m2 of wood can be impregnated with 1 kg of Silvaroyal® when applied by coating, pouring or short-term dipping, achieving impregnation depths of 1-3 mm, depending on the type of wood and wood treatment. For longer and better quality protection of outdoor wooden elements, we recommend a 24-hour dipping process or even a deep vacuum-pressure impregnation process.

At Silvaprodukt, we offer both 24-hour dipping and vacuum pressure impregnation services; the dipping procedure is also available at several different locations around Slovenia. For more detailed information and instructions, please contact us at info@silvaprodukt.si or via the phone number listed under the contact tab. We will be happy to advise you.

When protecting outdoor wooden elements, we recommend an additional surface protection with Silvanol stain B.

Silvanol will not be an effective enough protection for wood exposed to rain. If you want to preserve the same shade on the pergola and the garden furniture, we recommend using Silvaroyal® impregnation agent on both wooden surfaces before protecting and tinting with Silvanol stain B. You can see the shades of the Silvaroyal® + Silvanol stain B systemic protection on our website.

You can see the shades of the Silvaroyal® + Silvanol stain B systemic protection on our website. The left side of the scale shows Silvanol stain B shades on natural wood without an impregnating primer, the right side shows Silvanol stain B shades on wood, primed with Silvaroyal®.

In addition to its decorative protection, Silvanol stain B also increases the wood’s hydrophobicity and therefore effectively protects it from the weather. As Silvanol stain B is also a good vapour-permeable coating, it allows the wood to wick away moisture and thus prevents the creation of a favourable environment for the growth of decomposing fungi and other pests. However, protection with a surface coating alone is not enough for highly exposed wood, so we always recommend a systemic protection in the form of: primer + surface protection for the longevity of the wood.

It very easy to recoat wood with Silvanol stain B as it does not require any prior sanding, usually a short brushing with a coarse brush or washing with a high-pressure cleaner will suffice. Recoating is advisable when the coating loses its hydrophobicity, which can be checked by dripping a droplet of water on it. If the droplet is quickly absorbed, it is advisable to recoat the wood. Recoating is also advisable if the wood is cracking and showing its structure.

Thermally modified wood, which is not treated with chemicals but undergoes a heating process at 180-230 °C to change its structure and reduce its moisture content, which protects it from all wood pests and improves its dimensional stability, is very suitable for sauna constructions. You can supply us with the wood for thermal modification by prior arrangement, or for larger projects we can offer you pre-manufactured elements made from Silvapro® thermally modified wood, made to your specifications.

If the sauna is already made of unmodified wood, it can be protected with Silvaroyal® impregnating agent and Silvanol stain B if the wood is exposed to weathering, and it can be hydrophobicised with Silvacera® natural wax on the inside.

The first option is to use Silvapro® thermally modified wood with an additional surface waxing in Silvacera® shade 12, which gives the appearance of a partially patinated surface. Thus, the transition to a fully greyed-out shade is blurred and there are no obvious differences on the facade between the more and less weathered parts. You can supply us with the wood for thermal modification by prior arrangement, or for larger projects we can offer you pre-manufactured elements made from Silvapro® thermally modified wood, made to your specifications.

Alternatively, the wooden elements can be protected with Silvaroyal® wood preservative and painted with Silvanol stain B in the desired shade. This systemic solution avoids patination and greying of wooden facade surfaces. For longer and better quality protection of outdoor wooden elements, we recommend a 24-hour dipping process or even a deep vacuum-pressure impregnation process. At Silvaprodukt, we offer both 24-hour dipping and vacuum pressure impregnation services; the dipping procedure is also available at several different locations around Slovenia. For more detailed information and instructions, please contact us at info@silvaprodukt.si or via the phone number listed under the contact tab. We will be happy to advise you.

It is possible to thermally modify the boards, which is an environmentally friendly process for protecting the wood. We only use heat to change the structure of wood macromolecules and consequently improve the properties of wood. These changes are the result of spontaneous thermochemical reactions that take place when the wood is heated to temperatures of 180-230 °C in special oxygen-free chambers. Thermal modification significantly changes the structure and reduces humidity, which protects the wood from all wood pests and improves its dimensional stability. However, it should be noted, that for best fit the thermal modification procedure should be done first, and all milling operations for production of final elements afterwards. You can supply us with the wood for thermal modification by prior arrangement, or we can offer you pre-manufactured wooden elements made from thermally modified Silvapro® wood, made to your specifications.

Vacuum-pressure impregnation is still the most commonly used process for protecting children’s playground equipment and provides the highest quality protection for wood, as this method ensures the deepest penetration of the preservative into the wood.

It is also possible to thermally modify the wood of the play structures, which is an environmentally friendly wood protection process that does not use any chemicals, as the wood is protected using heat alone. However, it is advisable to use harder wood types such as oak, ash, beech, pine and larch for the thermal modification of wood intended for use in the construction of children’s playground elements, as the use of softer hardwoods such as spruce or fir is discouraged due to the increased potential for splintering.

Thermal modification significantly changes the structure and reduces humidity, which protects the wood from all wood pests and improves its dimensional stability. You can supply us with the wood for thermal modification by prior arrangement, or for larger projects we can offer you pre-manufactured elements made from Silvapro® thermally modified wood, made to your specifications. When using wood outdoors, we recommend additional protection with the environmentally friendly coating Silvanol stain B or Silvacera® natural wax.