Characteristics of various types of primers, requirements for solutions for impregnating bases, rules for choosing mixtures for concrete and wood surfaces. Primer is a pretreatment building block that strengthens the outer layer and improves adhesion to subsequent coatings. Correctly selected mixture increases the life of the floor. The article provides useful information about the properties of the primer and the principles of its choice.
Reasons for priming floors
The quality of the floor largely depends on the reliability of adhesion of the coating to the base and the strength of its adhesion with subsequent layers. If this is not enough, the top planks will lag and deform. To avoid trouble, the base is impregnated with special agents from a film-forming material (glue, resin, oil).
Concrete screed has low absorbency and poor adhesion to many materials. The reasons for the decline in concrete strength are well known. After the screed hardens, all the water evaporates, and voids remain inside it, weakening the concrete. As a result of mechanical action, the surface is abraded, dust appears. To find out which floor primer better strengthens the screed, let's study the effect of the solution on the material.
The simplest acrylic-based impregnating mixture contains glue diluted with water. The liquid penetrates into the screed and fills the pores. After the water dries, the adhesive remains and binds the concrete particles inside and outside, preventing the formation of dust.
After processing, concrete acquires the following properties:
- Adhesion to various materials increases;
- The consumption of subsequent coatings is reduced;
- The release of moisture is reduced, but the air supply is not blocked;
- No more dust on the surface;
- Increases resistance to damage;
- Microcracks are masked;
- The pores narrow in loose bases, in harder ones - they expand.
A primer for wood makes it possible to protect the material from external influences and provide a high-quality base for applying the topcoat. Impregnation allows:
- Reduce the consumption of paints and varnishes;
- Hide small defects - roughness, small cracks;
- Protect wood from mold and mildew;
- Increase adhesion to other materials;
- Maintain the natural color of the wood;
- Waterproofing the flooring;
- Increase the service life of the coating;
- Get rid of tree resin;
- Protect boards from insects;
- Create a transparent high-quality surface for varnish.
The main types of floor primers according to their composition
The need to use this or that tool is determined by many factors, but the main ones are its properties and the purpose of the procedure.
In private estates, the following solutions are most common:
- Alkyd primer … Designed for impregnating wooden floors before painting. After application, the structure of the top layer of the wood changes, which increases the adhesion with subsequent coatings. The product dries no more than 15 hours at a temperature of +15 degrees.
- Acrylic … It is made on a water basis and is considered universal. It can be used for processing any substrates - wood, concrete or chipboard. It strengthens well porous or very loose materials (eg old screed). It has the following advantages: diluted with water to the desired consistency; simple surface treatment; fast drying within 3 hours; lack of harmful vapors and pungent odor.
- Shellac mixtures … Used to impregnate softwood flooring before staining. It is often applied in places where the resin appears - near knots, at the ends, in places of cuts. It is made from the milky sap of insects. Dries up within 24 hours.
- Glyphthal Primer … It is applied on wooden floors to be painted with epoxy mortars. It is used only in dry rooms. Dries completely in a day.
- Perchlorovinyl … Its properties are similar to acrylic, but it emits toxic fumes, therefore it is not used in residential premises. Dries up after 1 hour.
- Polyvinyl acetate … It is used to prepare the substrate for indoor painting with polyvinyl acetate paints. The product contains latex and other synthetic components. Dries up in half an hour.
- Phenolic … Used as an initial coat for wood flooring. Has a strong unpleasant odor. It takes 10 to 15 hours to dry.
- Polystyrene … Designed for lumber and concrete substrates. Gives off toxic fumes, therefore it is not used in living rooms. It is applied on cement screeds. The drying time is indicated on the packaging.
- Polyurethane and epoxy primers … Designed for floor screed. They are made by adding a solvent to the dyes. They are used to prepare concrete surfaces for enamel application.
In order to save money at home, you can easily prepare a primer mixture from PVA glue and water, which are combined in a 1: 2 ratio. To do this, pour 250 g of glue into a container, add 0.5 liters of water, a little chalk and carefully move everything with an electric mixer. The higher the rotation speed, the better the water will dilute the glue. Usually, the base is covered with a mixture before installing tiles and linoleum.
Scope of floor primers
The composition of the screed is the main factor influencing the choice of the product; a large number of mixtures are intended only for bases made of specific materials.
Let's take a closer look at how to choose a primer, depending on its area of application:
- Mixtures for the impregnation of mineral surfaces, which include concrete and cement screed, contain an adhesive that strengthens the top layer. They are often used to renovate old floors with a minimum amount of cement. They act only on the depth of penetration, they will not save exfoliating cement floors.
- General purpose mortars are applied prior to painting to create an even and beautiful finish. When choosing products, consider the compatibility of the base material and the impregnation.
- Anti-alkaline agents are used for the treatment of floors containing alkali, such as new concrete, or substrates with fire-fighting additives.
- Impregnation "betonokontakt" is considered the best primer for floors and is used for the treatment of smooth hard substrates made of concrete and cement. The composition contains sand, which creates a roughness. After application, even smooth floors adhere well to the finish coat.
- Adhesive mixtures create a strong film with high adhesion rates. They are applied on poorly absorbent surfaces, for example, on previously painted surfaces, on which it is planned to put a cement screed. They have proven themselves well as a primer for self-leveling floors. However, the old coating must be compatible with the ingredients in the new product.
Depending on the need to strengthen the base, surface (strengthening) and deep penetration compounds are chosen. The former are used on solid floors that do not require hardening. In such materials, the liquid penetrates to a depth of only 2 mm. It differs from other solutions in color - it has a milky tint.
Deep penetration compounds are used to impregnate loose and weak substrates. They penetrate to a depth of 6-10 cm and not only strengthen the upper layers, but also increase the adhesion to the screed, paint or varnish. Usually it is a mixture of acrylic polymers, antiseptic and various biological additives. Often used for the renovation of old floors that cannot be dismantled. The color has an unclear shade.
Features of the selection of a primer for the floor
The choice of a primer depends on many factors, including the material of the floor. Let's dwell on this in more detail.
Choosing a concrete floor primer
When buying, ask about chemical resistance, the limit value of vibration load and other strength characteristics, take into account the operating conditions of the floor. In areas with heavy traffic, use high quality substances.
The impregnation must have the following properties:
- Penetrate to great depths;
- Do not form bubbles on the surface;
- Create high-strength transparent film;
- Lie down in an even layer;
- Reduce the consumption of the top layer of material
One of the types of primers is an independent protective agent-impregnation "betonokontakt", which is used when arranging concrete and cement floors, as well as for treating the base before laying tiles. Smooth surfaces are impregnated with solutions containing fine quartz sand. After processing with concrete contact, a coating is formed that resembles coarse sandpaper.
On solid substrates (made of M150 or M300 cement), special agents are applied, for example, epoxy mortars.
Concrete floor primer and subsequent coats must be well matched with each other, therefore the manufacturers of the primary treatment and the topcoat must be the same. For example, for Ceresit CT19 mortar, the paint must also be from Ceresit.
In damp rooms, concrete is impregnated with water-repellent mixtures, for example, "Moisture" or acrylic primer. They contain fungicidal additives that prevent the appearance of mold and mildew.
Features of choosing a primer for a wooden floor
Wood floors are impregnated with phenolic, glyphthalic, alkyd and polystyrene compounds. Each tool has its own characteristics and is suitable for use in certain situations.
Oil impregnations are made from linseed and wood oil, as well as from natural resins. The mixtures are deeply absorbed into the wood and create a hardened layer with a silky shade. If you have a choice, buy products based on natural oils, without solvents, which can be used to treat floors in rooms with high traffic and unheated rooms, for example, in corridors and on verandas.
Many formulations contain special additives that allow the tree to withstand adverse factors:
- Fire retardants protect lumber from fire. Often this agent is used to impregnate floors in public and industrial premises.
- Biocides and antiseptics prevent the appearance of fungus, mold, blue, and repel insects.
Wood floor primers can be superficial and deep, but at home, only external treatments can be done. At the factory, the boards are dipped in special liquids, which provides a completely different level of impregnation.
Correctly selected solutions allow you to obtain a high-quality base for paint or varnish:
- Transparent ones are used before varnishing the boards. The composition contains a special film former and dyes are completely absent. They perfectly emphasize the structure of the wood. The best colorless substances are those with casein-rosin fillers. Substances are not aggressive, do not destroy wood fibers and do not distort patterns.
- Opaque solutions are intended for preparing surfaces for painting. Before use, you must make sure that the substances will not react with each other.
- Cherry, fawn, brown or cream-colored products are suitable for nitro enamels or oil paints.
- Polystyrene impregnations are used only with paints of a similar base.
- Before finishing, floors made of natural wood, chipboard, fiberboard are often covered with alkyd solutions. If the floor primer contains linseed oil and pigments, the floorboards need not be painted. Such means are impregnated with wooden floorings on open verandas. The mixtures fill the pores of the boards well, prevent the appearance of rot and mold. The coating will give the wood aesthetics and increase the service life.
How to choose a primer for the floor - watch the video:
As you can see from the article, in each case, the primer is chosen individually, and the quality of the floor finish will largely depend on how responsibly you deal with this issue. Using our recommendations, you can make a durable flooring that will delight the owners for many years.
