Until recently, it was believed that self-leveling floors are the lot of exclusively industrial premises, and only specialists can make such floors. But modern technologies have made it possible to use self-leveling floors in residential premises, while making them available for self-assembly.
Self-leveling floors have a long history – the first such floors appeared in the late 80s of the last century in the USA. Initially, these were exclusively industrial floors, and were made on the basis of gypsum and cement. Over time, they began to be made on epoxy and polyurethane bases, which significantly expanded their field of application. If we list the main properties of self-leveling floors, then it immediately becomes clear that they are an ideal option for any premises with high requirements for performance and aesthetic appearance of floor coverings:
- high strength;
- resistance to aggressive environments – gasoline, solvents, alkalis and acids;
- abrasion resistance – dust does not form on the surface during operation;
- antibacterial – no foci of pathogenic bacteria form on the surface;
- high decorative properties.
According to the material used, self-leveling floors are divided into:
- cement-acrylic – based on cement mixtures. The most affordable. Most often they are used as a leveling base before laying other floor coverings or in rooms that do not impose high demands on the appearance of the floor;
- polyurethane floors – polyurethane base with the addition of a coloring pigment. Strong and elastic at the same time, therefore they are used in rooms with high dynamic and vibration loads. Absolutely dust-free. There are 2 and 1 component. They have the ability to color and use decorative elements – chips (flat pieces of paint), flocks (thin plates of a certain shape: stars, scales, etc.), sparkles (glitter), which gives a unique look to finished floors;
- epoxy floors – based on epoxy resins. They are very durable. They are less susceptible to aggressive media and withstand higher static loads than polyurethane. As well as polyurethane, they are easy to decorate;
- methyl methacrylate – based on methyl methacrylate resins. The most expensive, both in terms of material and cost of work. Similar to epoxy, but, unlike them, they can be applied at low temperatures and have the shortest curing time.
The first and most important stage is the preparation of the foundation.
Self-leveling floors are very demanding on the quality of the base. It is best to apply self-leveling floors on a concrete screed. Application on wood, metal or old tiles is allowed, the main thing is that these bases meet the following requirements:
- should be very even – irregularities of no more than 2 mm by 2 m are allowed;
- must not have traces of oil and grease;
- must be dry – humidity not more than 4–5%.
Thus, the work on the preparation of the foundation is divided into the following stages:
- Moisture check – if the surface to be prepared belongs to the lower floor, then it is necessary to make sure that there is waterproofing, and if it is not there, insulate it from groundwater. You can check the residual moisture in a simple way – cover the base area with plastic wrap, glue its perimeter with masking tape and leave for a day. If the next day condensation has formed under the film or the surface of the concrete screed has darkened, then self-leveling floors cannot be applied.
- Leveling – the surface is milled and sanded. Traces of absorbed oil are cut off. The resulting shells are sealed with concrete. After drying, the embedment sites are also leveled. If the specified work, for some reason, is impossible to carry out, or they do not give the desired effect, then it is necessary to make a new concrete screed.
- Dedusting – the base is thoroughly vacuumed with an industrial vacuum cleaner.
- Priming – after leveling and drying the base, the floor surface must be primed. At the beginning, cracks and expansion joints are freed from splintered particles. For priming, you can use any deep penetrating concrete primer, such as concrete contact or one-component varnish. For even application on the surface, it is better to use a roller, in the corners – a brush.
- Puttying cracks and chips – done after the first priming. Irregularities are putty, glued with fiberglass and sprinkled with quartz sand. Sprinkling will help further level the base. Puttying is best done with putties recommended by manufacturers of self-leveling floors..
- Re-priming. Produced after spackling. Upon completion, the surface is also sprinkled with quartz sand. If there was no need to putty, then the second layer of primer is applied after the first has dried. The surface after priming should be smooth and rough..
- Repeated dedusting – removes sand remaining after dusting.
It is necessary to know that bases made of high-strength concrete grades or those with a hardened top layer are not very suitable for applying polymer coatings, since they have poor adhesion to them. In this case, you will have to make a new screed or use another type of self-leveling floors, for example, epoxy floors..
After preparing the base, proceed to the application of the main layer..
Self-leveling floor application
The self-leveling floor is applied to the prepared substrate approximately 24 hours after priming.
First you need to prepare the following tool:
- squeegee is a fixed long-handled leveling knife. Serves for distribution and alignment of the base layer;
- needle roller – serves to remove air bubbles from the liquid base layer distributed over the base;
- soles for a self-leveling floor – used to move on liquid material;
- ribbon double-spiral mixer – serves for mixing the main material.
Further, strictly according to the instructions on the packaging, the filling material is prepared. It is best to do this in a separate room or designated area. Since movement in the pouring zone can only be carried out in clean, dry shoes, it is better that a separate person does the mixing work..
Liquid material is applied at temperatures from +5 to +25 ° С. Too low temperature will make the material too thick, which will prevent it from spreading, too large – will significantly reduce the solidification time of the prepared material.
The mixed liquid material is poured in strips onto the substrate, taking into account the required thickness, then leveled with a squeegee. Remember that 1 liter contains 1,000,000 cubic meters. mm, and in 1 sq. m 1,000,000 sq. mm. Thus, with the required thickness of 10 mm per 1 sq. m we need 10,000,000 cubic meters. mm, i.e. 10 liters of liquid material. It is similarly easy to calculate how many liters need to be poured per 1 sq. m base to obtain a liquid floor of the required thickness. If the material is not poured onto the entire required surface, then the next batch is docked no later than 40 minutes after applying the previous.
Not earlier than after 10 minutes, but not later than 40 minutes, the surface is carefully rolled with a needle roller. Movement on the surface is carried out in the soles for the self-leveling floor – flat shoes.
Despite the non-shrinkage of self-leveling floors, the seams in them must be provided. Seams are cut in liquid floors in places of expansion joints in concrete or joints of floor slabs, along the perimeter of the room and in the doorway. This is done by applying a foam expansion tape directly to the base before pouring the liquid floor material. If the concrete screed is more than a year old, then the seams are cut through one in relation to the concrete ones. After the filling layer has solidified, the tape is cut with a knife and the seams are sealed with a special sealant for self-leveling floors. Construction silicone sealant can be used.
If it is necessary to decorate the floor, then chips, flocks or glitter are used. They are applied on top of the liquid coating layer. If, when using flocks or sequins, roll the surface with a needle roller, you get a surface with a textured pattern throughout the entire thickness of the coating. After polymerization, the surface is covered from above with 2-3 layers of wear-resistant polyurethane varnish. The varnish on the finished floor can be applied in any convenient way.
A pattern can be applied to the floor for a personalized look. To do this, any image you like is applied to a hard, finished coating. This can be done both with the help of acrylic or polymer paints, and by sticking a pattern printed on a dense base. The last step will be to cover the surface with 2-3 layers of varnish. The pattern can be applied to any type of self-leveling floor, both polyurethane and epoxy floors.
Thus, if you properly prepare the surface and avoid mistakes in the process of preparing the mixture and pouring the floors, then the resulting self-leveling floors will serve for more than one decade..