How to make a floor screed with expanded clay with your own hands: recommendations

Expanded clay is a good heat-insulating material used when creating ceilings between floors, when building a foundation, for arranging attics, and also for creating a warm floor. Do-it-yourself floor screed with expanded clay is one of the easiest ways to level the floor, in which 3 backfill options can be used: expanded clay gravel, gravel or sand.

Expanded clay crushed stone is characterized by fraction sizes from 10 to 14 mm and is used to create concrete. Expanded clay gravel can be of three categories: with fraction sizes from 5 to 10 mm, from 10 to 20 mm and from 20 to 40 mm.

Used to create strong yet lightweight floors. Expanded clay sand is characterized by fractions up to 5 mm and is used to create thin screeds.

The choice of backfill type and its calculation directly depends on the screed technology, as well as on the type of room. For an ordinary living room, according to a standard recipe, you will need a pack of cement-sand mixture, weighing about 50-60 kg.

But if the load on the floor in the room is significant, as in industrial facilities, then a different calculation is applied and a different proportion will be required. But for warehouses with heavy equipment, expanded clay is not at all suitable, since this material will not withstand too much pressure.

Semi-dry screed

With this option floor screeds there is no need for too thorough preparation of the base. It is enough to remove the debris, sweep the floor surface, and also monitor the moisture that should not be on the floor. The floor screed with expanded clay should be carried out in a dry room, as it is necessary to protect the expanded clay from moisture, which often occurs on interfloor ceilings. To do this, after cleaning the floor surface, we cover it with a special vapor barrier film or PVC film.

Using a laser or rack level, we mark the size of the new screed, beating the lines on the wall and repeating them with a pencil. It is necessary to leave a gap along the perimeter of the walls with a calculation of at least 10 mm, which is necessary for inserting a heat-insulating material, which also provides additional sound insulation. For this purpose, you can use an edge tape. It remains to pour expanded clay on the floor and evenly distribute it over the surface using the usual rule.

Now you can either pour the solution directly onto the expanded clay, or separate it with a waterproofing layer. If the first option is chosen, then it is first necessary to fill the expanded clay with cement milk. If this is not done, then expanded clay granules, which are highly hygroscopic, will draw moisture out of the screed and so the shrinkage will be uneven.

Concrete screed

A concrete screed with expanded clay will have a certain thickness, depending on the curvature of the floor. Therefore, you must first determine how uneven the floor is. Such a calculation can be performed using a two-meter level, which must be placed in the corners of the room and find the center of the floor and wall interface line. Next, you should divide the room into zones and check each segment separately. Based on what curvature of the floor will be detected, it is necessary to calculate the thickness of the future screeds.

To create a solution, we pour expanded clay granules into a large metal container and add water in such a way that its level does not rise above the expanded clay by more than half a palm. Due to its porosity, expanded clay will absorb some of the water. It is necessary to stir the mixture and it will soon change its color. Now you can add cement and sand. We evenly distribute the resulting expanded clay concrete over the floor surface, level it and leave it for 2 days so that the floor screed with expanded clay dries.

Then you can either make another layer, or start finishing the floor.

Dry screed

Such coupler is carried out in several stages:

1. On a pre-prepared surface, we overlap a waterproofing material - a film. Laying should be carried out with the calculation of 6-7 cm on each wall and 20 cm of entry. With the help of construction tape, it is necessary to close the joints of the film, and close the joints with the walls around the entire perimeter of the room with a damper tape.
2. We install profiles - beacons necessary for the perfect alignment of expanded clay. It is easy to calculate their location and height: we set the level in the middle of the room, then, stepping back 5 mm from the corner, we screw a self-tapping screw into the floor, on which we put the rule and find its intersection point with the laser level. The second self-tapping screw must be screwed in, stepping back 20 cm, so that it runs strictly along the marked line. So it is necessary to do with the whole room.
3. We lay out a cement mortar on each of the screws, and put a profile on top of it and press it with sufficient force. The rest of the mixture must be removed with a spatula.
4. After the mixture is completely dry, we begin the batch filling of expanded clay. We level and after completing the backfill, we check the profiles using the rule, they should not sag.
5. It may be necessary to additionally compact the backfill with a polyurethane foam trowel. After leveling each section, we lay sheet material on it in two layers. If the sheets are thin, then we fasten them with glue or self-tapping screws.
6. Now it remains to seal the seams with putty and cover the sheets with a special bituminous waterproofing (optional). The remains of the tape, as well as the film, are cut off after the laying of the sheets is completed.

Advantages of expanded clay

Expanded clay is an environmentally friendly, lightweight and sufficiently durable material that has high heat and sound insulation performance. It has found its application in cases where it is required to raise the level of the floor. A screed with expanded clay in terms of its strength characteristics is not inferior to a screed made of cement and sand, but at the same time it has the ability to pass air, that is, to breathe.

Expanded clay can be used in any type of room, as it is not afraid of frost and heat, but you must first calculate the thickness of the embankment. Expanded clay does not burn, does not corrode, does not rot. And thanks to its extreme lightness, it is very easy to install, which can be done even without the help of professionals. With the help of this inexpensive, durable and lightweight material, it is very easy to level and insulate the floor in the apartment.