What is vermiculite and vermiculite concrete

Because it expands when heated, vermiculite is a naturally occurring mineral with a wide range of applications. It is a member of the phyllosilicate class of minerals, which are composed of layers. Vermiculite expands into long, worm-like particles during the exfoliation process, which occurs when it is heated to high temperatures. Because of this special quality, vermiculite is useful in the building, gardening, and other industries because it is lightweight and insulating.

In the construction industry, vermiculite and concrete are frequently mixed to create vermiculite concrete. This particular variety of concrete is highly valued for its exceptional insulating and fire-resistant qualities. Because vermiculite concrete is substantially lighter than regular concrete, the overall load on a building’s structure may be lessened. It is frequently utilized in soundproofing applications, steel structure insulation, and screeds for the roof and floors.

The remarkable quality of vermiculite concrete lies in its capacity to hold onto moisture while maintaining appropriate drainage. Because of this, it’s a great option for making thin, insulating layers in a variety of construction environments. Furthermore, the low thermal conductivity of vermiculite concrete contributes to energy efficiency by helping to maintain constant temperatures within buildings.

Builders and homeowners can choose their building materials more wisely if they are aware of the uses and advantages of vermiculite and vermiculite concrete. Vermiculite concrete has several benefits that can satisfy a variety of needs in the construction sector, regardless of whether you’re trying to lower the structural load or increase a building’s insulation.

Properties and composition

Vermiculite is a large filler that belongs to the group of hydromicas (formed in the process of hydration of phlogopite, as well as biotype), and by chemical composition to the category of aluminosilicates. It has a layered structure. Vermiculite contains 35% silicon, slightly less (up to 10%) magnesium, calcium, iron and other components. Natural insulation is distinguished by its crystalline and scaly form. But after processing under the influence of high temperatures, it takes the form of winding threads. And if you increase the temperature to 1000 degrees and above, you can get expanded vermiculite (EV), which is a loose material of a golden hue. In this form, the material has increased hygroscopicity (100 g of vermiculite can absorb up to 500 ml of liquid).

Practical! The water absorption range for vermiculite concrete tiles tested was 16% to 26%. Twenty-five freeze-thaw cycles later, the textured layer held together. Each tile lost between 0.7 and 2% of its weight at the same time.

Expanded vermiculite is the foundation for vermiculite concrete. Binders include bitumen, cement, dissolved glass, synthetic resins, and many more materials.

The material’s capacity to insulate against heat is another feature:

• Vermiculite density is from 250 to 400 kg/m3 .
• The thermal conductivity coefficient is in the range of 0.05-0.7 W (m*K). The indicator may vary slightly depending on how tightly the filler and its fractions are rammed.

Practical! Since BB has a heat absorption coefficient of no more than 5 W/m2 x hail, a screed made with this filler can be referred to as "warm."

• Compressive strength reaches 3.5 MN / m 2 (or 35 kgf / cm 2 ).
• Total porosity does not exceed 1% by volume.

Vermiculite that has been expanded resists fire better. Even at temperatures as high as 1100 degrees, the material’s characteristics remain unchanged. It can therefore be applied in a multitude of contexts.

Applications of vermiculite

Even gardeners use the material, adding it to the soil because of its high hygroscopicity. The truth is that it has the capacity to both absorb and "release" large amounts of liquid rapidly.

Additionally, this insulation is employed:

• In the production of slabs, blocks, shells and various segments when laying pipelines or industrial equipment.
• In the manufacture of structural and thermal insulation elements, such as floor slabs, wall panels, etc.
• As a bulk insulation when additional thermal insulation of ceilings or floors is required.

Practical! Good thermal insulation of the roof will require extra attention if vermiculite concrete is used for the attic flooring. Furthermore, a vapor-permeable membrane must be used. Additionally, a vapor barrier film needs to be applied to the interior of the space.

• For filling hollow niches in walls, pipelines, partitions.
• In the production of rigid slabs. They are more expensive, but vermiculite is not inferior in its characteristics to mineral wool, so there is no need to use it.
• In the manufacture of large-sized partitions.
• In interior and exterior finishing of buildings. Vermiculite has a pleasant color and texture.

Vermiculite grades

Vermiculite is made in compliance with GOST 12865-67 standards. Moreover, some businesses manufacture it in accordance with TU 5712-091-00281915-2007. Depending on the filler’s bulk density and fraction, the composition is indicated:

• M200. The size of vermiculite particles is no more than 0.5 mm. Density 150 kg / m 2 . Thermal conductivity index is 0.056 W/m°C at 25 degrees.
• M150. Particles with a fraction of up to 1 mm, the density of the mixture is 120 kg/m2 . Thermal conductivity level – 0.052 W/m°C.
• M100. Particle size up to 2 mm. Vermiculite density up to 100 kg/m2 . Thermal conductivity index – 0.047 W/m°C.
• M100 with particles up to 4 mm. Density is 80 kg/m2, and thermal conductivity is about 0.045 W/m°C.

When vermiculite is utilized as an extremely light filler, a material akin to perlite concrete is produced. Its features, however, are far superior to those of basic cellular concrete. Vermiculite concrete is also far simpler to prepare.

Manufacturing vermiculite concrete

Even though making vermiculite concrete is simple, you must choose the size of the material’s fraction right away.

Fraction and volume of filler

It is advised to use material with a fraction of less than 1 mm for experimental work. We are discussing non-grade, or second-rate, vermiculite, which is more difficult to locate. Lime and PC 300 are the greatest binders. It is advised to vibrate the concrete for at least one and a half minutes after laying it because it turns out to be fairly plastic.

The composition’s strength properties will be significantly reduced or eliminated if the mixture contains more than 70% of this type of filler. The truth is that the volume of binder in this instance is insufficient, which prevents the mica particles from adhering correctly. Lime milk can be added to the mixture if a significant amount of vermiculite has already been added. It will improve the concrete’s final strength properties.

It is preferable to select a filler with a fraction of 1 to 10 mm if you intend to produce facing slabs with an extra textured layer. As a binder, decorative cement works better. Only mineral pigments (which must first be tested for weather resistance) can be used as dyes. Lead that is iron red and brown ocher have the best properties.

The vermiculite fraction in a mixture intended for leveling the floor screed of a public or residential building should range from 0.6 to 2 mm. Because the aggregate particles are at this ideal size, their composition will be distributed uniformly. As a result, the screed forms fewer pores, which lowers the concrete’s thermal conductivity even further while increasing its strength.

Preparation of a screed mixture

In order to produce a light concrete mixture, PC400 ought to be given precedence. Additionally, adding more costly M500 brand cement will result in a 15–18% increase in the strength properties of the concrete. The table that follows shows the component proportions.

The composition must be mixed on the construction site right away using a mixer. Filling the cement is the first step, followed by adding water and sand. Vermiculite should only be added once you have homogenized these ingredients through kneading.

Wholesome To get a used and somewhat elastic mixture, there should be precisely this amount of water.

Use the prepared solution within 30 to 40 minutes. Consequently, specialized mortar pumps are frequently used to deliver mixtures to the location. Subsequently, the mixture can be laid manually or with the aid of a platform vibrator. It is advised to place beacons beforehand to create a more level surface. Concrete made of vermiculite should harden at temperatures above zero. After a week, the composition will become strong enough to start other floor tasks (grinding or puttying won’t be necessary once the screed has dried).

If a second underfloor heating system is to be installed, the cable system can be monolithically formed using a mixture that also contains vermiculite. As long as there is a 3–5 cm layer of vermiculite concrete, this is achievable.

Preparation of a solution for wall insulation

The ratios needed to prepare lightweight concrete with a thermal conductivity of 0.07 to 0.092 W / m x deg (heat absorption less than 5 W / m 2 x deg) are displayed in the table below. These concretes have a bulk density of about 280 kg/m3. These are the best combinations to insulate flat roofs or walls.

Numbers 5, 6, and 7 refer to self-supporting compositions; that is, increasing external loads are not permitted. These combinations are typically utilized as heat-insulators when building three-layer partitions. This could be a wall constructed of bricks, blocks, or any other type of material.

The heat transfer of traditional brickwork can be replaced with just 2 cm of vermiculite concrete if you prepare a solution in accordance with "recipes" 5, 6, or 7. Therefore, considering the layer of thermal insulation with BB, the wall’s characteristics will correspond to a partition of 7.5 bricks (about 1 m) if it has a bearing layer of one brick and cladding of half a brick.

It is advised to use mixtures 1, 2, 3, and 4 if the partition will be subjected to light loads during installation or operation. This is the ideal choice, for instance, for a flat roof. The vermiculite concrete layer’s thickness varies according to the local climate. For instance, it is advised to lay at least 12–20 cm in Siberia. One week after the concrete is laid, the roofing carpet installation can start. It’s also not necessary to level the screed any further.

Additionally, for indoor work, any of the compositions listed in the table can be used as plaster. Prior to choosing the best type of filler, it is advised to determine the installation work budget.

Topic	Details
What is Vermiculite?	Vermiculite is a natural mineral that expands when heated. It is lightweight, fire-resistant, and non-toxic, making it useful in various applications like gardening, insulation, and construction.
What is Vermiculite Concrete?	Vermiculite concrete is a lightweight concrete mix that uses vermiculite instead of traditional aggregates. It provides good insulation, is fire-resistant, and is used in places where reducing weight and increasing thermal performance are important.

A mineral that occurs naturally and expands when heated is vermiculite. Its special quality makes it very beneficial in many different industries, but construction is one of them. Vermiculite is a perfect ingredient for building materials like vermiculite concrete because it is fire-resistant, lightweight, and has good insulating properties.

One kind of lightweight concrete that uses vermiculite as an aggregate is called vermiculite concrete. This combination produces a material that is more acoustically and thermally insulated than regular concrete, while also being lighter. Because of these qualities, vermiculite concrete can be used for insulating concrete forms, floor slabs, and roof decks.

Beyond just its physical characteristics, vermiculite concrete has many advantages. In addition, it is simpler to use and manage, which cuts down on labor expenses and building time. Furthermore, because it is fire-resistant, buildings are safer because they have an additional layer of defense against fires.

Using the special properties of vermiculite to make concrete is a creative way to make a building material that is both effective and adaptable. For both residential and commercial applications, vermiculite concrete provides a cost-efficient and environmentally friendly answer to today’s building requirements.

A naturally occurring mineral called vermiculite expands when heated to produce light-weight, fire-resistant particles that are frequently used in gardening and construction. Because of its exceptional insulating qualities, low density, and fire resistance, vermiculite concrete—which is created by combining vermiculite with cement and water—is highly valued for its use in lightweight concrete applications, including floor and roof screeds, pipe insulation, and as a lightweight aggregate in structural concrete. This cutting-edge material combines improved safety features with ease of use to provide a flexible and useful solution for a range of building needs.

Video on the topic

What is vermiculite for.

Vermiculite and perlite. Visual difference using pelargonium as an example. I answer questions

Garden head – What is vermiculite for

Vermiculite in construction.Vermiculite plastering

Perlite or Vermiculite – which is better

USEFUL PROPERTIES OF VERMICULITE AND PERLITE! WHAT IS THE DIFFERENCE?

WHAT THIS IS VERMICULITE?

What is vermiculite?