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Waterproofing on wood works

Wood as a material combines experience of nature with a rustic aesthetic. Weather and use cause wooden surfaces to age quickly. To preserve the charm of wooden objects, nanoCare provides waterproofing that works. Your wood remains young and easy to care for.


Protect wood effectively with the right waterproofing

Everyone knows it: If the cosy acacia garden furniture or the beautiful wooden table is not covered and dried in time for the thunderstorm, the sensitive surface can quickly show signs of weathering. However, before you resort to the next best wood preservative or paint and brush, you should do some research into waterproofing wood. In this way, even as an inexperienced do-it-yourselfer, you can see what is important in wood preservation and avoid annoying and above all costly mistakes.


  • No greying 

Waterproofing keeps wood young. Exposed to daily weathering, wood becomes grey and matt. Wood waterproofing provides lasting protection for the material.


  • Water repellent effect

If unprocessed wood is exposed to water, water will penetrate. Cracks and crevices are the result. Waterproofing has a water-repellent effect and protects against ageing Effect


  • The waterproofed UV-protection 

Like any surface, wood used outdoors is at risk of being exposed to an ageing process due to UV rays. Here, waterproofing acts like sun protection.


  • Moulds

An indirect consequence of the unprotected penetration of water is molds. Waterproofing prevents unpleasant infestation.


  • Weatherproof

Wood is a robust natural material. Without bark and unprocessed, wood is quickly exposed to signs of ageing. To maintain its resistance to wind, sun and rain, all you need to do is waterproofin

Why the wood waterproofing works.

The generic term wood waterproofing covers various wood protection processes. The aim of the various types of treatment is to protect the wood preventively against various organisms that could discolour or destroy the wood or - if there is already an infestation - to combat these harmful organisms. Preventive waterproofing of wood should always have priority. The waterproofing agent penetrates deep into the wood and acts on the surface and in depth: the wood is protected against, mould and weathering.

Possible applications

Waterproofing wood in a do-it-yourself process

Hobby craftsmen who want to waterproof wood apply the wood preservative by brushing or spraying. No special equipment or exceptional manual skills are required for such work. However, before you start work with fresh courage, you should inform yourself about the individual work steps and learn valuable tips to achieve a good result. In this way you can be sure that the wood will remain attractive for a long time and will fully fulfil its purpos.


What do I have to pay attention to when waterproofing wood?

If you want to waterproof your garden furniture or other wooden parts outdoors, you should choose an area that is as shady as possible for the work to be carried out. UV radiation can cause changes in some wood preservatives as long as they are fresh and not dried. Never waterproof wood at extreme outdoor temperatures! Frost and heat are disadvantageous when waterproofing. A temperature range of 5 - 25 °C is ideal for processing most agents. Pay attention to the manufacturer's label when choosing a brush. Not every brush is recommended for glazes or paints containing special solvents. 

The individual work steps in waterproofing wood

1. Preparation of the substrate

Before waterproofing, the wood must be cleaned of any dirt and smoothed. This is best done by sanding with emery paper (grain 150 - 200). The sanding dust is thoroughly removed with a soft brush and a slightly damp cloth. 


2. Apply first coat

The (mostly colourless) waterproofing is applied evenly with a brush recommended for the solvent used. Work with long strokes in the direction of the grain. If possible, work over the entire surface in one go. This is the easiest way to avoid streaking. 


3. Intermediate sanding

Ideally, the first waterproofing should be left to dry for at least 12 hours. Avoid direct sunlight during drying to avoid the risk of discolouring the wood. Experience shows that the application of the liquid and the subsequent drying process creates fine wood fibres which are removed by intermediate sanding. Fine sandpaper with a grain size of 280 - 320 is recommended for intermediate sanding. At the same time the entire surface is evenly roughened by sanding and becomes more absorbent for the next coat. The sanding dust must first be removed again with a soft brush and a slightly damp cloth.


4. Applying the second layer

In order for the wood preservative to develop its full effect, a second application of waterproofing agent is necessary. After a drying time of at least 12 hours, you can additionally apply a colour of your choice or a colourless varnish. If you apply a primer beforehand, the colour adheres more reliably and has a higher covering power.



In practice, various methods are used to apply or apply wood preservatives to wood. The deeper the wood preservative penetrates into the wood, the more effective is the protection achieved by waterproofing. The depth of penetration depends on the chosen method and the type of wood to be waterproofed. Apart from painting and spraying, which is the preferred method of most hobby craftsmen, there are other waterproofing methods, some of which we would like to introduce to you briefly.


During dipping, the wood is placed completely in a tub filled with wood preservative for a few minutes to several hours. A few minutes' exposure time will result in a penetration depth comparable to the effect to be achieved when painting. With longer application times, the penetration depth can reach several millimetres. This method is mainly used in the professional sector. With small quantities, the relatively high demand for wood preservatives would be uneconomical


Hot-cold immersion

In this process the wood is alternately bathed in hot and cold wood preservative. If the wood is in the hot bath, the air inside the wood expands. When changing to the cold bath, there is a suction effect that promotes the penetration of the wood preservative. With the hot-cold impregnation, penetration depths of 30 - 50 mm can be achieved.


Osmosis process

This process is based on the diffusion principle. In this case, the wood preservative is not liquid but paste-like. It is applied to the wood surface on undried wood. The treated wood is stacked tightly and carefully covered. It is left to stand for up to 3 months so that the wood preservative can diffuse into the wood and develop its protective effect.


Boiler pressure waterproofing and boiler vacuum pressure waterproofing

The wood preservation technologies described so far are pressureless processes. In industry, the waterproofing agent is often pressed into the wood at high pressure (up to 10 bar). In most cases, a more even distribution of the waterproofing agent can be achieved in this way than with pressureless processes. Not every type of wood is suitable for waterproofing under pressure. Larch and Douglas fir wood is conditionally suitable for pressure impregnation. This process cannot be used for spruce and fir wood.


A solid and professionally executed waterproofing protects wooden furniture and building components against the penetration of moisture. At the same time, it prevents the penetration of fungi, micro-organisms and harmful insects that discolour and destroy the wood. In addition, modern wood preservatives offer effective protection against UV radiation.

Waterproofing is much more effective than conventional priming, as it penetrates deeper into the wood and thus protects it more effectively. Waterproofing agents are usually colourless. Nevertheless, the appearance of the wood is visibly improved. The wood looks fresher and more alive. The grain becomes more attractive. The primer spreads over the surface and does not penetrate as deeply as the waterproofing. Waterproofing should always be the first step in effective wood protection. If desired, after thorough drying, paint or another design agent can be applied


This question cannot be answered in a generalised way because the durability of waterproofing is influenced by several factors. The protective effect varies from species to species and the ingredients of the wood preservative also play a role. Wood that is exposed to rain and sun unprotected must be re-treated after a shorter time than a garden chair, which is almost always under a protective roof. 


The various types of wood used in the manufacture of garden furniture and for outdoor buildings are differently susceptible to attack by blue stain fungi and damage from weathering. Spruce, fir and pine are very susceptible and must be protected carefully. Oak and Robinia are considered to be particularly robust and resistant. 

The deeper the wood preservative penetrates into the wood, the more effective it is. With methods used in the private sector, only penetration depths of about 1 mm can be achieved. For this reason, waterproofing should be repeated regularly to effectively prolong the life of the wood.

Unprotected wood often turns bluish after a short time. The cause of this discolouration is the blue stain fungus, which feeds on the ingredients of the wood cells. Although it does not destroy the wood, it significantly impairs the appearance of the wood surface. If there is already a severe infestation of the sapstain fungus, this can affect the impregnability of the wood.

The wood protection of a waterproofing is limited in time. How long the waterproofing effect lasts cannot be stated in general terms, as the effect depends on the type of wood, the penetration depth of the wood preservative and the intensity of external influences (precipitation, temperature, UV radiation), among other things. As soon as the wood surface feels rough and turns greyish, it is time for a new treatment.

This depends on the type of wood preservative used, the thickness of the application and the environmental conditions. The lower the temperatures during impregnation and the higher the humidity, the longer the wood must dry after treatment. Several hours should definitely be planned. As a rule, the instructions for use provided by the wood preservative manufacturer will tell you after how long a second coat can be applied and after which time, for example, garden furniture can be put into use. 

Water-based wood preservatives should be applied with a brush made of plastic bristles. Glazes can be applied evenly and without forming stripes with a brush with natural bristles. However, there are not only different types of bristles, but also many different brush shapes. Ring brushes are characterised by a high colour retention capacity. As the ring brush can be turned easily, you can work very precisely and cleanly. The latter is especially important when painting windows, for example. If waterproofing of wood involves larger areas, flat brushes are recommended, which are available in different widths from the trade. For very large areas, paint rollers are also used.