How many coats of polyurethane do you need? Ultimate Guides

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how many coats of polyurethane

Well-kept parquet floors have always been a sign of the good taste of the owners. When choosing a protective coating, you need to be able to strike a clear balance between aesthetics and reliability. Polyurethane parquet varnish allows creating a surface with high wear resistance without sacrificing beauty. How many coats of polyurethane do you need and several types of this material we will look through in this article.

Table of Contents

  1. Application and characteristics of polyurethane varnish for wood
  2. General characteristics and properties of polyurethane varnish for wood
  3. The main properties of polyurethane varnish for wood
  4. Types of polyurethane varnishes
  5. Benefits of polyurethane varnishes
  6. Disadvantages of polyurethane varnishes
  7. Varnish application technology
  8. Recommendations for the use of polyurethane varnishes
  9. Consumption of polyurethane self-leveling floor
  10. Choosing a composition
  11. How to calculate the required amount of bulk liquid
  12. Characteristics of a polyurethane floor
  13. Conclusion
  14. Video how many coats of polyurethane do you need

Application and characteristics of polyurethane varnish for wood

During operation, home parquet, furniture and other wood products are constantly exposed to high loads and are negatively influenced by the external environment. High air humidity, spilled liquid or mechanical damage cause irreparable damage to an expensive coating and worsen its original appearance. Polyurethane varnish for wood will help to solve the problem, which will provide surfaces with high-quality protection and significantly increase their service life.

General characteristics and properties of polyurethane varnish for wood

Polyurethane varnishes for wood have established themselves as the most durable and reliable coatings for all types of wood. They are based on hydro-acid and alkyd-urethane resins mixed with aliphatic hydrocarbons, special additives or dyes. The special formula of the polymers that make up the material ensures their rapid hardening and, when the components enter into a reaction, contributes to the formation of a film with excellent indicators of elasticity, strength and moisture resistance.

The main properties of polyurethane varnish for wood

Consumption – on average 60-100 ml per 1 m².

Drying speed – from 4 to 12 hours tack-free at a temperature of + 25 ° C.

Durability – not less than 10 years.

Heat resistance – up to 110 ° С.

how many coats of polyurethane on table

Types of polyurethane varnishes

The main purpose of polyurethane varnish for wood is decorative and protective varnishing of wooden surfaces that are exposed to increased operational loads. It is widely used for the treatment of floors, stairs, countertops, furniture, doors, window frames. The composition can be applied to products that were previously coated with polyurethane, nitrocellulose or alkyd materials based on organic solvents.

The modern industry produces a wide range of polyurethane varnishes for wood, differing in content, color and degree of gloss. Based on their preferred end result, customers can choose a clear polyurethane varnish or a product with pigments that give the wood a specific shade.

Depending on the chemical composition, the material is of two types:

One component is a liquid polyurethane varnish (often water based) that can be applied to the surface without prior preparation.

Two-component – a product consisting of a polymer base and a hardener. Before application, its components are mixed together according to the manufacturer’s instructions.

Based on the appearance, the compositions are:

Glossy – give the room an attractive look, especially if, after drying, they are polished with special polishing pastes. However, scratches and other defects are clearly visible on the glossy coating, therefore it is undesirable to use them in rooms with high mechanical stress. As a variety of such varnish, semi-gloss and silky-gloss compositions are distinguished.

Matt – look good in rooms with diffused light. Using such a polyurethane varnish for wood, you can hide the imperfections of the floor and the consequences of its unskilled processing. In addition to the matte lacquer itself, manufacturers offer semi-matt and silky-matte materials.

water based polyurethane

Benefits of polyurethane varnishes

The gloss grading allows users to select the polyurethane varnish for wood according to their preference or overall interior design.

In online stores you can find any type of the specified products and choose the most acceptable option at competitive prices.

In recent years, polyurethane varnishes for wood have been in high demand on the market, because they have excellent performance characteristics and have reliably served for many years. A barely noticeable lash formed after their application does not allow moisture to pass through and protects the wood from mechanical stress. After processing, the material evenly spreads over the base and is well absorbed into the pores of the wood, without interfering with the “breathing” of the wood surface.

It is worth mentioning that varnishes on polyurethane are a good solution for giving the interior a presentable look, as they create a perfectly smooth finish and emphasize the natural pattern of the wood.

The main advantages of polyurethane varnishes for wood include:

good adhesion – the varnish adheres firmly to the surface and does not peel off even when applied to a polished base;

resistance to abrasion and mechanical damage – the product is not afraid of impacts and retains its original appearance for many years;

resistance to aggressive environment – products coated with polyurethane varnish for wood can be cleaned with household chemicals;

resistance to moisture – varnishes do not allow water to pass through and reliably protect wood from swelling;

lack of smell both upon application and after drying, which allows the use of the compositions in the bedroom or children’s room;

cost-effective – do not need multiple applications (1-2 coats are enough).

Disadvantages of polyurethane varnishes

The popularity of polyurethane wood varnish among consumers is largely due to the fact that it has practically no drawbacks. The only disadvantages of the material include:

– fear of alcohol and alcohol-containing products (if they get on the coating, indelible stains may appear);

– quite high cost;

– short-term life cycle of two-component varnishes (after mixing they must be used within 12 hours).

Varnish application technology

Before applying polyurethane varnish for wood, it is necessary to thoroughly prepare the surface – clean it from dirt and dust, sand it, free it from lint and polish it. If the substrate is being treated for the first time, it is recommended to cover it with special synthetic impregnations, which will provide additional protection against fungus, microorganisms and mold.

You can use a brush, roller or spray to varnish the surface. A brush and roller is usually used on small surfaces (such as furniture), while a spray gun will be more effective on parquet or wood floors. The technology for applying polyurethane varnish for wood includes several successive stages:

Material preparation. If a two-component polyurethane varnish is used, all its components are mixed with each other and kept for some time to remove air bubbles (from 15 to 60 minutes).

Application of varnish. First, the base is covered with the first layer of the composition. Then they take a break from work (usually at least 12 hours) so that the surface is completely dry. After drying, the tree is treated with sandpaper, dust is removed and a second layer of varnish is applied.

The final stage. To make the coating look more effective and last a long time, after the final drying of the material, it is covered with polishing pastes.

oil based polyurethane

Recommendations for the use of polyurethane varnishes

Working with polyurethane varnishes for wood requires compliance with certain conditions. First of all, it is necessary to provide a special temperature regime in the room where the varnishing will be carried out. The air temperature should not be higher than + 25 ° C and not lower than + 18 ° C, humidity – in the range from 25 to 60%.

When working with a brush, the polyurethane varnish is applied along the wood grain. If a roller is used, the base is covered in a criss-cross pattern for a smoother streak-free finish. When treating the floor, it is best to apply varnish from window to door, leaving unpainted stripes to be able to leave the room.

One-component formulations can be slightly thinned with an organic solvent at the rate of 5% for brushing and 15% for spray. Two-component polyurethane varnishes for wood are prepared in strict accordance with the manufacturer’s recommendations, otherwise you can get a mixture that is too viscous or too fast to cure.

Before buying a varnish, it is advisable to inform the seller about the conditions in which the tree will be used in the future. Professional consultants who will answer any questions in detail and select the most suitable composition for you.

Consumption of polyurethane self-leveling floor

Polyurethane flooring is a popular way to equip a room with high traffic and weight loads on the floor. During the installation process, it is important to take into account many factors – the method of mixing and application, drying, processing, etc. In order to avoid unnecessary costs, it is necessary to calculate in advance the consumption of the polyurethane self-leveling floor per m2 and the entire area.

Choosing a composition

Before filling, you need to determine the type of composition that will be used for this:

One-component. It is applied in one layer up to a millimeter. Suitable for premises with an average level of traffic – no traffic, freight trolleys and constant pedestrian flow. Performs a decorative function – with the help of a color scheme, it is painted in the desired color or applied to create a pattern. Since the layer is no more than a millimeter, the consumption is minimum 0.4-0.6 kg per 1 m2.

Two-component. It is applied in several layers, with a total thickness of three to six millimeters. If cars move in the room, heavy objects are transported, high permeability, a layer of quartz sand is created between the underlying and subsequent layers. The polymer volume will depend on the number of layers and their thickness, on average 2.4 kg per 1 m2 at 2 mm thickness.

How to calculate the required amount of bulk liquid

Factors on which the amount of building material that will be required for pouring depends:

  • Number of layers and total thickness. For each millimeter of the reservoir, based on an area of ​​one square meter, there is about a liter of bulk mixture.
  • Floor areas. The amount obtained from the calculation of the total thickness is multiplied by the number of square meters in the room.
  • The presence of a sandy layer. If it is necessary to harden the coating, quartz sand is used. In this case, the displacement increases by one and a half to two times. It depends on how rough the surface you want to get in the end. The higher the smoothness, the more polyurethane should be poured onto the sand.
  • Density of the composition, one-component or two-component. The minimum flow rate is calculated based on how quickly the material spreads over the surface. Average values ​​are 1.5-2 kg per square meter. To get an exact sum, the number obtained after multiplying the thickness and area is multiplied by the density. The total volume of the material is obtained, taking into account the thickness of the layer, the area of ​​the room and the density of the mixture.

The presence of heavy fillers in the composition makes the mixture more viscous, which increases its use. Cement and other “weights” are added to increase the strength and durability of the flooring. Before choosing the level of density of the material, it is necessary to decide what strength is needed – low, medium, high.

polyurethane floor

Characteristics of a polyurethane floor

Basic properties and characteristics of the composition and finished coating:

  • after mixing, the material “lives” for about forty minutes – during this time it must be distributed over the floor;
  • a high level of adhesion – not only with concrete, but also with other floor materials;
  • filling is possible only at positive temperatures, starting from +5 degrees;
  • he self-leveling floor can be used only three days after the final filling of all layers – for pedestrians, after a week – for transport;
  • high resistance to mechanical, shock and weight impact;
  • does not create dust, easy to clean;
  • resistance to moisture and chemicals.


So if you want to equip a high-quality, reliable and beautiful floor in your apartment or house, then pay attention to polyurethane floors. As you know now they have appeared not so long ago, but have occupied a solid niche among the main types of flooring. They have a lot of advantages with almost no disadvantages. It is quite possible to fill such floors on your own – for this you do not need complex equipment or any specific skills.

Video how many coats of polyurethane do you need

Date: 15.11.2021