Negative characteristics of polystyrene foam
According to its parameters, expanded polystyrene is not very suitable for wood, since it does not breathe, while wood has such a need. This material is also unacceptable for the installation of roofs with wooden truss systems. The surface of the blocks can be destroyed by exposure to the sun and high temperatures. However, if we are talking about walls, then the base of the PPS boards can be covered with a layer of plaster, which is applied to a special steel mesh, in some cases the traditional painting method is used.
Pros of Styrofoam
- high rigidity;
- ability to endure heavy loads;
- good thermal performance;
- not saturated with moisture;
- frost resistance;
- long service life.
Cons of Styrofoam
- collapses under the influence of the sun;
- not recommended for use with internal insulation;
- cannot be fixed on wooden walls.
What are the proportions of foam chips with cement
The implementation of the screed with cement mortar will entail a load on the overlapping slabs. This is very bad, so in order to significantly reduce it, you need to add foam chips to the cement mixture. An important aspect is the increase in heat and sound insulation.
Before adding the crumb to the cement, it must be treated with a special solution.
You can use this crumb:
- crushed, obtained by grinding foam pieces;
- primary, specially produced for use in mortars.
The first type is cheaper than the second.
What is the proportion of foam crumb cement for concrete mortar? Everything is pretty simple:
- 4 to 5 buckets of small foam plastic chips;
- 1 part of cement brand M 500;
- 2 parts coarse sand;
- 1 part water.
Use a concrete mixer to mix all components. It will take you no more than 5 minutes, and the result will be a slightly dry mixture, somewhat reminiscent of buckwheat in appearance.
Crushed concrete - negative points
As already mentioned, a mixture of mortar with a light filler (foam crumb) has a high level of sound insulation and thermal insulation. In addition, this material is not porous and does not absorb moisture.
But foam balls, interacting with cement mortar and sand, do not differ in durability. The action of oxygen causes their destruction. They will completely collapse in about 20 years.
That is why concrete with the presence of foam chips must be plastered. In addition, such material as polystyrene is not completely harmless. Since the foam balls, in cooperation with sand and cement, become non-combustible, when heated, they simply melt and release toxic gas.
Instructions for the preparation of concrete with foam chips
First you need to load sand and cement into the concrete mixer. After that, fall asleep crumbs. At this stage, mix the components and only then add water. The proportions of foam chips with cement must be taken into account so that the mixture does not crumble later. After mixing all the components, add water and bring the solution to a homogeneous state.
The finished product will have the following characteristics that positively distinguish it from pure concrete:
- Decreased heat conduction;
- Lightening weight, with the ability to reduce the load on the foundation;
- Increased sound insulation;
- Significant cost reduction.
But, despite all the advantages, the strength of this product is clearly not enough. In order for this indicator to be normal, it is necessary to maintain the ratio of foam chips and other components.
Characteristics in numbers
Characteristics of extruded polystyrene foam.
The heat-saving characteristics of polystyrene foam blocks are based on the fact that air has one of the lowest thermal conductivity values, which is 0.027 W / mK, for this reason, the thermal conductivity of a heater based on it is equal to the limit of 0.037-0.043 W / mK. This is much less than the thermal conductivity of wood, which is 0.12 W/mK. Thus, 12 cm of such insulation is equal to a brick wall, the thickness of which is equivalent to 210 cm, the thickness of a wood-based wall of 45 cm is equal to the same indicator. These characteristics make expanded polystyrene a leader among heat insulators.
In addition to water resistance, expanded polystyrene is characterized by the fact that the material is not able to dissolve in water and deform, as well as swell. The percentage of water penetration by the mechanism of capillary diffusion is 1.5-3% relative to the weight of the polystyrene foam block. The same diffusion mechanism contributes to the expulsion of moisture from the material. Water vapor is able to penetrate the slabs at a rate of 1% of the rate of movement of steam in airspace. Steam is also quite easily removed from the heater. Condensation can be avoided by following the design technology.
The density of the plates is low and equal to the limit of 0.015-0.05 g/cm3, for comparison, the density of water is 1.0 g/cm3. But along with this, expanded polystyrene has high compressive and bending strength. As an example, we can consider the use of slabs during the repair and construction of runways and highways.
Comparative characteristics of insulation from expanded polystyrene and mineral wool.
The cellular structure of the material explains its excellent sound-proofing and noise-absorbing characteristics. To ensure good sound insulation, a plate with a thickness of 3 cm will suffice. If you increase the thickness of the layer, these properties will become more impressive.
The lower limit for expanded polystyrene in temperature equivalent is -1800°C, and the upper limit is +800°C. But the maximum possible temperature, to which the material can be exposed for some short time, is considered to be + 950 ° C. This allows the insulation to be exposed to hot bitumen. If the insulation begins to undergo exposure to temperatures above + 800 ° C for a longer time, it will begin to collapse.
Expanded polystyrene is characterized by high fire resistance. The temperature at which spontaneous combustion of the material can occur is +4910°C. Despite the fact that the plates are subject to combustion, they do not support it, and in the absence of fire they are able to die out within 4 seconds. In other words, the material will burn only with an open flame. Today on sale you can find polystyrene foam boards enriched with flame retardants and are self-extinguishing.
https://youtube.com/watch?v=Ea94bC7aIp0
Fixed formwork can be made from expanded polystyrene, however, the main area of application of the material is the insulation of low-rise buildings. You should not insulate log houses with them if you do not plan to equip a ventilated facade.
Blocks with cladding and insulation as the best materials for thermal insulation of your home
Whatever type of thermal insulation you choose, the insulation process will invariably include such elements as a directly mounted wall, a layer of insulation and an external finish.
However, not so long ago, a small revolution occurred on the building materials market: special blocks appeared with built-in insulation and cladding. Thus, now it is possible to work not with several layers, but only with one, which greatly simplifies the process and reduces time costs.
What are insulation blocks?
Innovative blocks with cladding and insulation as a base provide a dense layer of expanded clay concrete.The insulation in them is usually expanded polystyrene, although this composition may vary between manufacturers. For example, polyurethane foam, mineral wool and honeycomb are suitable.
Specific preferences depend on the wishes of the customer and the type of residential facility. The structural elements of the insulation are bonded together with fiberglass or metal.
The outer decorative layer is textured concrete, which prevents negative environmental influences. It is thinner than the main layer - only 1.5 - 3 centimeters.
Multilayer blocks have a wide palette of shades, so you can choose them for every taste. The front surface can be represented by natural stone, sandstone or wood - almost unlimited scope for stylish design.
Properties of blocks with cladding and insulation
Materials for thermal insulation of your home, such as sandwich blocks, have important advantages over other materials. So, if you decide to use a more familiar version of outdoor insulation, then for a great effect you would definitely have to make a wall at least 50 centimeters thick. Agree, this does not inspire optimism.
And what are the other benefits?
- Layered blocks have a huge margin of safety. They are very reliable, since the layers in them are in close contact by means of reinforcing bars. In general, the final design is guaranteed to be complete.
- Eco-friendliness is a nice addition to your home. Unlike separately located heat insulators, in this case there is no tendency to ingress of moisture, that is, it does not need to be treated with waterproofing insulators. Accordingly, the walls of the house are not threatened with bioinfection with mold and fungus. In addition, corrosion is also not terrible.
- Multilayer blocks combine the features of both stone and wood - they "breathe", adjusting the humidity in the building itself.
- Among other advantages, the very quality of thermal insulation achieved by means such as blocks with lining and insulation is at its best. They are very resistant to temperature extremes, frost-resistant. And at the same time, the walls, as you remember, will have a low density - only 30-35 centimeters, so you don’t have to sacrifice usable area.
- High fire resistance is an important component of the thermal insulation of the house. In the case of expanded clay concrete blocks, a potential fire not only will not destroy them, but on the contrary, will make them stronger.
- They are mounted quickly and without problems, and even at the construction stage. And it is not at all necessary for a bricklayer to be highly qualified.
- Expanded clay blocks are cheaper than many heat-insulating analogues.
Block dimensions
Multi-layer block materials for the thermal insulation of your home in the standard package have the following dimensions:
- height - 20 centimeters;
- width - from 25 to 40 centimeters. More common are 30-35 centimeters;
- length - 40 centimeters.
As you can easily imagine, blocks with cladding and insulation do not differ in large sizes, which means that it is convenient to work with them. Such material does not carry a large load on the foundation of the house. Blocks are laid by a method similar to bricks.
For installation, you will need fittings (it should be laid in three rows), a level and a wooden hammer. Cement-sand mortar is prepared in a ratio of 3:1. Upon completion of laying, a reinforced concrete structure is fixed along the height of the working wall - a support for the rafters.
The amount of material needed is calculated as follows: the total length of the wall, taking into account the partitions, is multiplied by the height of the prospective ceiling. Then this figure must be divided by the height and length of the multi-layer block, if the wall construction technology includes masonry 2 blocks thick, then multiply the resulting number by 2.
Summing up, it is worth noting that such multi-layer blocks can turn the process of thermal insulation of a house into a simple event that does not require overwork from you.
