Gypsum bulk floor is a dry building mixture, which, in addition to the main material, includes quartz sand and special plasticizing additives that increase the plasticity of the mortar. The finished coating has a high pour point. Therefore, in a short time it is necessary to carry out all the filling work so that the floor maintains its operational characteristics for a long time.
Properties and main features
The difference between bulk floors from other types of screeds is that they require very high quality preparation of the base. Under them do not lay waterproofing and insulation materials, so as not to reduce adhesion to the bearing surface.
Bulk floor is very expensive. It is usually equipped with a thin layer in combination with cement or gypsum. This option is more affordable. Plaster bulk floor is cheaper, since this material is considered relatively inexpensive. But its distinguishing feature is its high pour point.
The adhesion of the solution to the base occurs after 5 minutes after the preparation of the solution. The time of using the material for 10 minutes without loss of quality is allowed, and after 20 minutes it already becomes unusable. In order to slow down the curing process a bit, a borax solution is added to the mixture.
The composition of the gypsum bulk floor from different manufacturers has no significant differences. Therefore, there can be no strict recommendations regarding companies. The basis of any mixture is gypsum and quartz sand.
Advantages and disadvantages
A unique feature and the main advantage of the gypsum mixture is its curious ability. First, it absorbs moisture, and then give it away, maintaining the optimal level of humidity in the room. Other advantages of the gypsum-based bulk floor include the following:
- This coating is completely uniform and smooth. It hardens much faster than a cement screed, so the likelihood of bumps and cracks is minimized.
- The finished mixture spreads very evenly over the finished base.
- Gypsum coating regulates the humidity in the room, as it is able not only to absorb excess moisture, but also to give, if necessary.
- Gypsum mixture can be poured not only using special machines, but also manually.
The gypsum composition also has some disadvantages. Despite the fact that it can absorb moisture, it cannot absorb a large amount of water in the room. Because of this, it will quickly collapse, therefore, a gypsum-based coating is not recommended to be equipped in the bathroom and in the kitchen. Another disadvantage is that the gypsum screed is incompatible with the adhesive solution. It can not be laid as a basis for a tile floor.
Foundation preparation
Gypsum bulk floor requires high-quality leveling of the base. There are four ways to pre-prepare the surface:
- Contact coating. This method consists in the fact that after thorough cleaning of the base, it must be primed. To do this, an edge tape is laid out and fixed along the perimeter of the walls, and then it is treated with a primer to the height of the future bulk floor.
- Filling the floor with the equipment of the separation layer. In this case, no priming is required. Paper is laid on the prepared surface (it must be rolled out over the entire area). The material is sold in rolls, it is necessary to calculate in advance how much it will need for the entire surface. Tapes are overlapped by 10 centimeters.
- Laying special waterproofing material. The installation method is identical to the separation layer equipment, but waterproofing is used instead of paper. Surface priming is not applicable here either.
- Pouring gypsum mixture onto a warm floor. Heating does not harm the composition, since it is characterized by good resistance to temperature loads.
Necessary tools
To apply the gypsum mixture to the floor, a squeegee having a steel sheet is used. This is a special spatula with teeth that quickly form a screed of the required thickness.
As beacons, which help to monitor the uniformity of coverage, benchmarks are used. In any solution, bubbles form when the composition is mixed with water. After such a screed hardens, pores can remain on the floor, which will damage the coating and make it less durable. Remove these bubbles from the floor with a needle roller.
To level the solution on the floor, you have to walk on it in shoes with studded soles (kraskostozh). Do not step on a still wet floor without this shoe, otherwise dents will form on the surface.
To protect the screed from cracking during drying, a damper tape is fixed along the perimeter of the wall. Also, for the work required: level, construction mixer, primer, roller and a plastic bucket.
Solution preparation and implementation
Not everyone knows how to properly fill the bulk floor. For work, it is necessary to prepare a mixture of dry powder and water. It is important to observe all proportions, otherwise the coating will not be of high quality. Correctly kneaded solution in consistency resembles condensed milk. The amount of water depends on the composition chosen.
The powder is poured into water at room temperature and thoroughly stirred until the mixture acquires a uniform consistency. Stir the composition for at least 3 minutes, then let it stand for 7 minutes and stir again.
When the solution is completely ready, it is carefully poured onto the prepared surface and distributed with a squeegee over the entire area. Using a needle roller, the surface is carefully leveled and allowed to dry. No more than 30 minutes are allowed for the entire operation, otherwise the gypsum-based composition will harden.
The bulk floor should be filled with windows and doors closed to protect it from drafts. Also, direct sunlight is harmful to him, so it is better to hang light curtains on the windows. Drying should occur naturally, heaters must not be used, this can cause cracks to form on the surface.
Not the last role in the arrangement of the coating is the question of how much the gypsum bulk floor dries. Professionals do not recommend exposing this surface to stress before 12 hours. For greater reliability, it is best not to walk on the cover for 24 hours.
Pouring work can be done independently. Usually on any package there is an instruction for preparing the composition, all the proportions are clearly stated there. If you have doubts about your own strengths, it is better to entrust the work to specialists.
Professionals Recommendations
A strong and even coating will be obtained if you follow certain rules during installation. The gypsum-based composition hardens quickly, so it is recommended to divide the floor filling in a room of more than 9 m² into several stages. Each section is poured in turn. The uniformity of the layers is checked using a level.
To prepare a solution from the finished mixture, which can be bought at construction stores, you need to use tap water. Pouring work is best done in 20 minutes (the deadline is 30 minutes).
The temperature in the room where the floor is being filled must not be less than + 5 ° C. During all work it is necessary to use a respirator, goggles and gloves.