Expanded polystyrene is a popular material for thermal insulation of building structures. One of the most common forms is the slab. They are easy to install, have good technical characteristics and are notable for their low price. There are different ways of laying the material, which you should familiarize yourself with before carrying out installation work.
Purpose and composition of the material
Expanded polystyrene boards have been produced for several decades. The material is suitable for insulating walls, ceilings, roofs, foundations, facades, floors and other building structures. There are two main types of polystyrene foam used - regular foam and extruded polystyrene foam. The second material is an improved version of the foam.
The composition of expanded polystyrene includes polystyrene, polydichlorostyrene, styrene copolymers, foaming agents (hydrocarbons, blowing agents, freons), various additives in the form of dyes, modifiers and fire retardants.
There are various ways of producing expanded polystyrene tiles, but two are common:
- Pressless suspension. Due to suspension polymerization, granules with a liquid are obtained. By heating, they increase in size and form a cellular structure. It turns out polystyrene.
- Extrusion. The granules are mixed with a blowing agent at high pressure and temperature and then removed from the extruder. The result is a material that has a uniform structure with closed pores and cells up to 200 microns in size.
Expanded polystyrene plates are widely used in insulation - internal and external. It is a material with good technical characteristics and an easy installation method. Plates with a foil layer are produced. It reflects heat into the interior of the room.
The most popular types of expanded polystyrene are products marked PSB S 59, PSB S 25, PSB S 15. The abbreviation is deciphered as follows: PS - expanded polystyrene, B - pressless, C - self-extinguishing. The numbers indicate the maximum sheet density.
Main technical characteristics
Extruded polystyrene foam properties:
- thermal conductivity 0.028-0.034 W / m × K;
- material density 28-45 kg / m3;
- water absorption by volume for 30 days 0.4%;
- working temperatures -50 ° С to + 70 ° С.
Extruded polystyrene foam has better performance compared to foam. It has high compressive strength, absorbs less moisture and has little steam permeability.
Advantages and disadvantages
The advantages of expanded polystyrene boards include:
- Good resistance to heat transfer.
- Ease. The minimum weight of expanded polystyrene heat-insulating aphids is ensured by their structure.
- Simplicity and ease of installation. The material is easy to cut into pieces, it does not require a complicated fastening method.
- Possibility of covering with plaster, putty and other decorative finishes.
- High strength.
- Low cost.
- Duration of operation.
- Environmental friendliness and safety for human health.
- Resistant to biological corrosion.
- Increased moisture resistance and low absorbency.
The main disadvantages of the material include:
- Fire hazard.If you use expanded polystyrene boards without fire retardants, which create a protective fire-resistant film, the risk of fire increases.
- Low vapor permeability. Additional ventilation is required.
- The expanded polystyrene panels can be damaged by rodents.
- Poor resistance to organic solvents.
- When the temperature rises above 160 ° C, styrene is released.
Despite the shortcomings, expanded polystyrene is a popular and reliable material for building insulation. It is convenient and easy to work with, it is available in all regions of the country and effectively copes with its task.
The use of insulation
The availability of the material and its properties have made expanded polystyrene a popular insulation. It can be used as a heat insulator in some types of household appliances, and is often used in packaging.
Wall insulation in buildings is carried out with PSB-S foam of different density, which is selected depending on the place of application. Greater breathability allows it to be used for residential premises with the creation of a more comfortable microclimate. The use of PSB-S slabs in external insulation is associated with the absence of the need for a layer of steam and waterproofing, the possibility of applying finishing materials directly to the sheets of the heat insulator.
Selection recommendations
Expanded polystyrene is produced by various well-known brands. To choose the best look, you need to use the following tips:
- Preliminary study the parameters of the offered products. It is necessary to decide on the place of installation of the insulation, climatic conditions, the required thickness of the plates.
- Checking the standards by which the heat insulator is manufactured. If products are manufactured not according to GOST, but according to the company's own technical conditions, the characteristics may differ. In the name PBS-S 40, the density ranges from 28 to 40 kg / m3. This variation is due to the lower cost of producing less dense sheets. A more precise value can be found in the documentation for polystyrene foam.
- Before making a purchase, it is recommended to break off a small piece of material from the edge of the sheet. If the product is low-grade, the foam will break with an uneven edge, and balls will be visible on the sides. In a material made by the extrusion method, the fracture will be even with the shape of regular polyhedrons. Some of them will have a fault line.
It is important to pay attention to the company that produces polystyrene boards. High-quality products are produced by European companies from Germany, Finland, Poland. Well-known manufacturers are Polimeri Europa, Nova Chemicals, BASF. Of the Russian brands, Penoplex, Technonikol can be distinguished. For several decades they have been producing insulation based on expanded polystyrene and have the appropriate production capacity. The products sold have excellent properties and characteristics.
You should buy insulation only in professional stores. In them, the products have the necessary licenses and certificates, as well as guarantees.