Wood varnish for exterior use - types of compositions and their features. Choosing wood varnish for external and internal use Wood varnish types and areas of application

Wood remains a popular building material. Aesthetics, practicality, versatility, good thermal insulation properties are only part of the advantages, but the main disadvantage is low resistance to moisture. You can correct the situation if you use wood varnish for exterior work. Manufacturers produce different types of coatings, which differ in technical properties.

Characteristics of varnishes for outdoor use

The service life of wooden surfaces and products is affected by atmospheric phenomena, temperature changes, and sunlight. The paint coating allows you to provide reliable protection to the wood if the varnish is chosen correctly.

When choosing paint materials, it is important to pay attention to the following characteristics:

Moisture resistance. From moisture and water, the tree begins to rot and collapse. The varnish should create a durable moisture-resistant layer on the surface that will prevent moisture from penetrating into the wood.
Frost resistance. The property is determined by its waterproof capabilities. The coating should easily withstand sub-zero temperatures without damage or deformation. If the material, after drying, does not have sufficient water-repellent properties, then water will penetrate into microcracks. When it freezes, it will expand in volume, damaging the coating.
Wear resistance. There are varnishes with different wear resistance. For terraces, piers, stairs and other places with high loads, you should choose compounds with good wear resistance. For fences, facades, vertical surfaces and products not subject to heavy loads, paintwork materials with average wear resistance are suitable.
UV resistance. The composition must contain additives that provide protection from ultraviolet rays. Otherwise, the coating will quickly fade from constant exposure to the sun.
Strength and resistance to mechanical damage. Wood is considered a soft material and needs to be reliably protected from mechanical damage. The varnish coating must be durable.
Drying time. The indicator can be from 2-4 hours to several days, depending on whether a quick-drying or regular composition is used. Drying time depends on environmental conditions.
Resistant to temperature changes. The coating must be durable, but at the same time elastic, so that it can be easily deformed by temperature changes without the appearance of cracks or other defects.

Types of wood varnishes for outdoor use

Depending on the components in the composition, there are several types of varnishes, which differ from each other in properties and characteristics.

Oil based varnishes

The main component of such paints and varnishes is refined oil. The composition includes synthetic or natural resins. For the most part, they provide reliable protection to the tree. Colorless oil-based paints and varnishes are rarely found on sale. They are presented in a wide range of colors - from light yellow to dark brown.

The main advantages include:

environmental safety;
good resistance to moisture;
high coating strength;
availability.

And although the varnish forms a durable coating, it does not interfere with air exchange. The main disadvantage is the long drying time (1-3 days). It is recommended to apply paintwork in sunny weather at temperatures above +10 degrees. Oil-based formulations are often thick, making them difficult to apply with a brush.

Polyurethane varnishes

Depending on the composition, they can be one-component or two-component. In the second case, a hardener is additionally used. Polyurethane-based paint and varnish material is versatile, as it is used for painting facades, fences, terraces, etc. It forms a durable coating on the surface that has good elasticity (does not deform due to temperature changes).

Polyurethane-based facade varnish has the following advantages:

coating strength, resistance to mechanical loads;
moisture-repellent properties;
resistance to ultraviolet radiation and chemicals;
adhesion to surface;
quick drying.

It is allowed to paint only dry wooden surfaces. Upon contact with water, the composition loses its performance properties.

The main disadvantage is the higher cost compared to other types of paints and varnishes.

Alkyd varnishes

The main raw materials for production are glypthal and pentaphthalic resins. Solvent or white spirit is used as a solvent. Sometimes manufacturers add special substances that speed up the drying process.

The material forms a moisture and ultraviolet resistant film on the surface. It tolerates temperature and humidity changes and atmospheric conditions well. Typically used for painting surfaces that are not subject to heavy loads, as it has low wear resistance.

Main advantages:

decorative (emphasizes the structure of the tree);
resistance to mold and fungi;
affordable price;
ease of application.

The main disadvantage is the long drying time (24-72 hours). When dry, the varnish emits a strong, unpleasant odor. To reduce this drawback, it is worth choosing a composition with special additives.

Water-based varnishes

Acrylic varnish is usually produced based on a water dispersion. The composition may contain a solvent, but its content does not exceed 15%. The main advantage of coatings is environmental safety. It has no unpleasant odor and is non-toxic. It can be transparent or colored, it highlights the structure of the wood well. Surfaces painted with acrylic varnish are reliably protected from moisture, mold, and fungi. Used for surfaces that are not subject to heavy loads, since wear resistance is weak.

Manufacturers produce two-component water-based varnishes. In addition to acrylic, they contain polyurethane. In this regard, they have the best technical characteristics. They form a durable coating that is resistant to mechanical stress, ultraviolet radiation and moisture.

Yacht trains

Frost-resistant and moisture-resistant yacht varnish forms a durable coating on the surface. Initially, it was created for painting yachts and ships, so the main focus was on excellent performance characteristics and durability. Over time, the scope of application has expanded.

Even with constant exposure to atmospheric conditions, temperature changes and other negative factors, the coating can last a long time. An important advantage is versatility (can be used for horizontal and vertical surfaces). Disadvantage: high toxicity.

Step-by-step instructions for applying varnish

You can varnish wooden surfaces yourself if you have general information about the features of applying paints and varnishes. For the work you will need an accessible tool. It is not necessary to have special skills.

Varnish consumption

type of wood (porous surface absorbs more varnish);
material viscosity;
quality of preparation of the surface to be painted;
method of application.

When applying the first layer, the varnish consumption is usually greater, then it is used more economically. If you use a spray gun, you will need less material than if you paint with a brush or roller.

Selecting Tools

The selection of the necessary tools depends on the method of applying the material. The spray gun is usually used by professionals. If you don’t have this professional equipment, you can get by with hand tools. You can varnish wood with a brush or roller. Brushes will need different widths depending on the characteristics of the surface to be painted. The roller is convenient to use for covering large flat surfaces – terraces, fences, etc.

It is important to take care of personal protection. While working, you should use gloves and a respirator.

Surface preparation

At the preparatory stage, you should perform the following steps:

Sand the surface thoroughly. Use sandpaper of different grits for this. The work can be done manually or using grinding machines.
Remove all dust with a vacuum cleaner.
Proceed to the next step if the surface is clean and dry.

If there is no vacuum cleaner, sweep away the dust with a brush, and then wipe the entire surface with a slightly damp cloth and allow to dry completely before applying primer or varnish.

Primer

The primer composition is used to improve adhesion, level the surface (eliminate minor irregularities), and improve the performance characteristics of the varnish coating.

Apply the primer to the cleaned and prepared surface with a brush. The composition should be selected depending on the type of paintwork material. The primer should be applied in a thin layer. Once dry, sand and re-primer. The number of layers depends on the general condition of the wood and the desired effect.

Applying varnish

Before applying, waterproof wood varnish must be mixed well so that the contents of the jar become a homogeneous mixture. If the composition is too thick, it is diluted with a solvent to the required consistency. The paintwork should be applied from top to bottom in a thin layer. Make sure the coating is even. If drips appear, they must be removed immediately.

When the first layer has dried, it is sanded with fine sandpaper and then re-opened. The varnish is applied in at least 3 layers, sometimes more. Each layer must be sanded. The final coating is sometimes polished to achieve a beautiful shine and a smooth surface.

If you choose and apply varnish correctly to a wooden surface, you can reliably protect it from weather conditions and other factors. When choosing, you should focus on operating conditions and take into account the cost.

Varnishes are used to protect wood products and give them various effects. There are a large number of varieties of this material, differing in technical characteristics and areas of application. We will tell you in this article how to choose the right substance for wood processing.

What is varnish and where is it used?

Varnish is a viscous liquid that is applied to the surface of a wooden product and covers it with a thin film. It hardens over time. This substance contains resins and various polymers, which are usually dissolved in special solvents.

Looking at the catalog of the best varnishes, it can be noted that thanks to them the following problems are solved:

the appearance of the wood is preserved and emphasis is placed on its texture;
surfaces are decorated;
the tree is protected from putrefactive processes and damage;
help improve thermal insulation.

This material can be used for internal and external work. Its properties and scope of application depend on the structure. If you need to create a solid base, then it is advisable to buy an alkyd-urea variety; to protect against moisture, buy an alkyd substance, and to cover surfaces subject to heavy loads, buy an oil one.

There are 5 categories based on the degree of gloss, as can be seen from the photo of wood varnish:

regular matte gives less than 10% gloss;
semi-matte 10-15%;
semi-gloss 40-50%;
glossy 80-90%;
super glossy over 90% gloss.

Varieties by area of application

You need to choose the material depending on the area of use. After all, different surfaces and operating conditions require different technological qualities.

For interior work

By covering wooden structures indoors with liquid, you not only provide them with decorative properties, but also protect them from external influences. There are special substances for parquet and furniture, as well as universal materials.

The floor covering must be reliably protected, because it is under constant load. At the same time, you can choose the effect you prefer by purchasing glossy or matte wood varnish.

You also need to select the composition for different rooms. After all, in the bedroom the load on the parquet will be less than in the hallway or living room. Therefore, in the second case, higher quality material with additional protection will be required.

Experts also recommend selecting parquet coatings based on the degree of transparency, consistency and method of application. Parameters such as resistance to ultraviolet radiation and stress are also important. Among the substances used for flooring, primer, water-soluble, polyurethane, alkyd, and formaldehyde types are popular.

To protect furniture, high-quality and expensive analogues are used. They must maintain the natural appearance of wood. Therefore, the polyurethane type of material is most often used. It is also permissible to use oil, alkyd, acrylic and alcohol compounds.

It is important that the coating does not retain odor and that the film hardens quickly. Therefore, quick-drying wood varnish when processing furniture can be indispensable when carrying out urgent work.

External use

To protect structures located outside the home, a more durable coating is required. Therefore, the selected material must guarantee resistance to external weather factors and mechanical damage. They cover facades, gazebos, decking, fences, log houses, etc.

A variation of this group can be alkyd-based yacht varnish for wood. It is harmful and is used only for processing wooden ships, but not for interior work. Safer is the yacht look based on urethane-alkyd.

Types by composition

A wide variety of liquids for finishing wooden surfaces are on sale. Their specificity is the presence of certain substances in the structure.

Oily

This type of paint and varnish is widely used in interior finishing work, but is not suitable for flooring. Contains oil and resin. Fatty and medium-fat mixtures perfectly cover the surface, protecting it. But materials with a fat content of less than 50% serve only the role of decorative finishing.

Increasing the amount of resin speeds up the hardening process, but this reduces strength. The color of the substance varies from yellowish to brown. Drying time 24-72 hours.

Alkyd

High-quality coatings that dry within 48 hours are used in interior and exterior work and provide a very durable coating on different types of wood. The composition is moisture-resistant, resistant to ultraviolet radiation, temperature changes and moisture. Used for treating floors and furniture. Thanks to additives, drying speed can be increased.

Acrylic

This is the safest type of paintwork. Water-based acrylic varnish for wood is odorless and highly fire-resistant. The resulting film is not sensitive to ultraviolet radiation, but is exposed to moisture.

Nitrovarnishes

Such mixtures are weakly resistant to ultraviolet liquids, the use of which is limited to internal work. Can be used for processing different types of wood. Penetrate into the product and create a strong protective film.

An important advantage is the drying speed - only a few hours. The composition contains toxic solvents, so work is carried out only in a respirator.

Polyurethane

They may have a two-component structure of a base and a hardener or additionally contain a solvent. They are characterized by increased adhesion, but have a pungent odor and harden within 15-20 days. The hard film protects surfaces from moisture, corrosion and chemical components. Therefore, varnish is used to treat yachts and ships, gazebos, and parquet.

Polyester

They are distinguished by their multicomponent nature; the resin of the same name is used as a base. It is applied to the surface with a special gun.

As a result, a durable transparent film is formed on the processed parts, which is particularly durable, moisture-resistant, and resistant to elevated temperatures and chemical reagents. It is used to coat objects that require a glossy effect, such as musical instruments.

Epoxy

These are moisture-resistant, impact-resistant paintwork materials, having a two-component composition based on epoxy resin. They cover flooring, doors, and solid floors. For example, epoxy varnish for tikkurila wood is popular.

When processing wood when carrying out interior or exterior work, you should use high-quality paints and varnishes. They must be selected depending on the type of structure, operating conditions and the expected external visual effect.

Photo of wood varnish

All photos from the article

If you need to protect wooden structures located outdoors, then you cannot do without special compounds. At the same time, compositions for outdoor use differ from those used indoors, so it is important to understand their varieties and the main features of each option.

This is what this review will focus on.

Oil-based solutions

This option has several main differences:

The basis is highly purified natural oils, which are thermally treated and give the solution certain properties. The durability of the coating largely depends on the quality of the base, so the cost of high-quality options cannot be low.
The second important component is resins, which can be either natural or synthetic, and in modern products it is the second option that is most often found.
After coating, the surface darkens, the drying time is quite long, so if you do the work yourself, then choose a day with low humidity and air temperatures above 10 degrees.

The main types of such varnishes are the following:

Yacht varnish for exterior woodwork is also called phenolic resin varnish and is used to coat surfaces that will be constantly exposed to moisture. The finished coating is elastic, thanks to which it maintains its integrity during swelling and drying of wood, which are inevitable during the operation of many structures.
Polyurethane varnish is also very popular for a number of positive properties: simple instructions for carrying out the work - you can paint the base with your own hands and ensure high quality work. The composition dries quite quickly and creates a durable and abrasion-resistant surface, which, depending on the type, can be matte or glossy.

Solvent based solutions

Another large group of products, which is also used quite often.

This option has its own differences:

The basis of all varnishes is a solvent, as it evaporates and the composition dries. The drying time is about a day, which is a minus.
The protective layer has high properties: resistance to abrasion and deformation, durability of the coating.
The surface can be washed using detergents, which is also very important if the elements are susceptible to contamination.
In order to change the consistency of the composition or wash off the varnish from your hands and other surfaces, you will need a solvent (its brand is indicated on the packaging with the composition).
After drying, the material acquires a yellowish tint, which is a disadvantage.

Water-based varnishes

Without a doubt, this is the most popular and sought after option today.

This group of compounds has a number of undeniable advantages:

The compositions are made on the basis of an aqueous dispersion with a small addition of solvent. Thanks to this, it is possible to carry out work in rooms where people are located; there is practically no smell during work, as well as fumes that are harmful to health.
The colors of water-based exterior wood varnish can be very diverse, and this is one of the biggest advantages. You can choose any option that will be combined with the rest of the elements on your site, while the solution, while giving the surface the desired shade, does not hide the beauty of the wood structure.

Water-based varnish can be made with the addition of various components; the most popular option is acrylic varnish for exterior woodwork; it has an affordable cost and good performance properties and is used to cover various structures that will not be subject to high loads.
The second popular solution is polyurethane-based varnishes; this component provides excellent abrasion resistance, so such solutions are used to paint surfaces that will be walked on during use.

Advice! There are other options: alkyd, alkyd-urethane, etc. - they all have their own characteristics, which are indicated on the label. Therefore, please read the information provided carefully.

Conclusion

Choosing a high-quality composition is very important, since not only the appearance of wood products, but also their durability depends on it. The video in this article will tell useful information regarding the topic discussed ().

For exterior woodwork, a special frost-resistant varnish must be used. This composition can be used for decoration and protection of wooden products that are located outdoors.

Exterior varnish will extend the life of wooden surfaces

In winter, wooden structures can be significantly affected by negative temperatures, which impair the performance properties of the surface. For example, if moisture penetrates into the structure of a tree in winter, then when it freezes, the liquid can expand and lead to the destruction of the coating. Therefore, any frost-resistant varnish used for exterior work must have pronounced water-repellent properties.

Today, frost-resistant paint and varnish compositions are actively used for painting the following wooden surfaces:

roof elements;
steps made of wood;
porch;
outdoor wood furniture;
terrace boards;
bath walls;
wooden sculptures.

All these surfaces need not only protection from moisture, ultraviolet radiation, mold and fungi, but also from exposure to extremely low temperatures.

Varieties of frost-resistant compounds

Today the choice of varnishes is large, the main thing is not to make a mistake, and for this you need to know a number of criteria, which are given below

Today there is a large selection of paints and varnishes for exterior use. Basically, all of them do not affect the natural wood texture and do not change the shade of the surface. Modern materials with a frost-resistant effect can have an oil, water and organic base. Any of these compositions forms an elastic film after drying, which increases the surface’s resistance to mechanical stress at low temperatures.

In addition, paint and varnish material for external use contains various chemical additives that protect the coating from fungal attack, ultraviolet radiation, cracking and discoloration.

Key characteristics on which the effectiveness of frost-resistant coating depends:

water-repellent properties;
permeability to vaporous substances;
resistance to mechanical deformation;
resistance to ultraviolet rays;
impact resistance.

The main types of frost-resistant varnishes depending on the composition:

solvent-based paints and varnishes;
water-based varnishes;
compositions based on alkyd-urethane;
oil solutions;
yacht paint and varnish compositions.

Yacht varnish is frost-resistant, wear-resistant and highly durable

Types depending on purpose:

universal formulations;
varnishes for wooden furniture;
glossy paint and varnish coatings;
matte coatings.

Popular paint and varnish compositions are solvent-based coatings. The composition hardens after complete evaporation of the solvent. As a result, a high-strength film is formed. This frost-resistant varnish is ideal for outdoor use, as it is resistant to abrasion and the chemical effects of detergents. However, solvent-based coatings can change the color of the wood surface, adding yellow tones.

Frost-resistant varnish with a water-soluble base is not as resistant to abrasion. At the same time, such material is considered more environmentally friendly. In addition, water-based material dries faster than all others.

The most durable varnish is considered to be one created on an alkyd-polyurethane base. It has excellent performance characteristics. A feature of oil-based paints and varnishes based on natural resins is that they can change the color of a country floor or other wooden surface, making it darker.

Today, woodworking has become popular for outdoor work. This paint and varnish material has all the necessary qualities in terms of elasticity and durability that are required for such compositions. It has increased frost resistance, as well as pronounced water-repellent and dirt-repellent characteristics. In addition, frost-resistant varnish of this type is applied without any problems and does not leave smudges.

Application method

Frost-resistant varnish should only be used after the surface has been coated with impregnation. It is recommended to apply the paintwork in 2 or 3 layers. All work must be carried out at a positive temperature. The paint and varnish material can be applied using a regular brush, roller or pneumatic sprayer. If you are going to work with a sprayer, then it is best to dilute the paint and varnish composition. The solvent used must match the composition of the varnish.

Before applying each subsequent layer, the wooden surface must be sanded to improve its adhesion. At the same time, the next layer should be applied no earlier than four hours after painting.

Thus, frost-resistant varnish is very effective for outdoor woodwork. It allows you to protect the wooden surface from the negative effects of low temperatures and other adverse environmental influences.

Over time, many materials lose their original appearance. Wooden products and buildings are exposed to external factors and need regular updating. To restore wood, it is recommended to use wood varnish. Unlike paints, it has a transparent texture, which helps preserve the original design.

The varnish will give an aesthetic appearance and emphasize the natural beauty, as well as reliably protect the product from adverse events and prevent its destruction.

Varnishing wood

The principle of working with wood varnish is to apply it to the surface. As a result, the solvent contained in the substance will evaporate and a dense and shiny film will remain. These simple steps will help extend the life of the wood.

Of course, for an impeccable result, it is necessary to perform a number of preliminary measures. First, sand the wooden surface and remove any remaining old paint or varnish. After sanding, be sure to remove any remaining dust.

Secondly, it is very important to apply the primer varnish first. This will avoid the appearance of bubbles and prevent the formation of small defects.

Then you can apply the varnish, having previously chosen the desired tone. Thanks to the wide range of products on the sales market, you can choose the right color to match the interior of the room.

Types of varnishes

It is necessary to choose a varnish taking into account the upcoming work (internal or external) and operating conditions (humidity and temperature levels).

Let's consider the following most popular categories of varnish products:

Oil varnish

Oil solutions are based on vegetable oils and resins. This is a wood varnish intended for interior use. They are distinguished by the degree of fat content.

Accordingly, the fattier the product, the better the protective layer. Colorless varnish is most popular in this category, as it helps preserve the natural texture of the wood.

Alkyd varnish

Alkyd varnishes are distinguished by their versatility in use (intended for internal and external manipulations). They have increased resistance to external adverse conditions, are not afraid of moisture and high (low) temperatures. This safe and environmentally friendly product has a relatively low cost.

Alcohol varnish

Alcohol varnish contains ethyl alcohol and resin as a base. It is mainly used to coat furniture accessories and musical instruments.

Acrylic lacquer

Acrylic varnish for wood is odorless and contains antiseptics designed to combat mold and fungi. It is very convenient to use due to plasticizing additives that allow you to simulate the substance. Available in a wide range of colors and is environmentally friendly to use.

Water based varnish

Water-based wood varnish contains water, emulsifiers and, in some cases, solvents (from 5 to 15 percent). Despite the fact that it dries much longer than other products, it is in demand among buyers due to the consistency of price and quality. They are absolutely not flammable.

Polyester varnish

Polyester based on polyester resin creates a dense, thick glossy, water resistant film. It can only be applied using a special device.

Polyurethane varnish

Polyurethane, on the contrary, has a pungent odor and takes a long time to harden, but in the end it forms an unconditional protective layer.

Alkyd-urea varnish

Alkyd-urea varnish is considered very durable and water-resistant due to the acid hardener, urea and resin it contains. Excellent for covering parquet as it has a special shine.

Conclusion

Well-known manufacturers present a wide selection of wood varnishes. They are characterized by the type of application (internal or external use), by the type of solvent used as a basis and by the degree of gloss.

Thus, oil varnish will protect the surface from dust and dirt, while alkyd varnish can create a barrier against moisture. Alkyd-urea compounds are designed to strengthen the surface and create a more durable coating.

When choosing, you need to take into account the gloss of the varnish. Exclusive options are already presented on the sales market: tinting varnishes. With their help, you can change not only the shade, but also the color of the tree.

To decide where to buy wood varnish, you need to visit several hardware stores, study the assortment of each, consult with specialists and select the right product.