Warming the foundation of the house outside with expanded polystyrene - step by step instructions!

Foundation - the basis on which depends not only the durability and strength of the building, but also its thermal insulation qualities. Without additional protection of this part of the building, about 20% of the heat will go out of the room. To prevent heat loss, you should use special materials - insulation.

Expanded polystyrene is one of the most common types of thermal insulation, used in almost any part of the building. It is used to protect foundations, façades and roofs, as well as to create custom blocks that allow the restoration of almost any damaged decorative element in old buildings.

Expanded polystyrene production

Expanded polystyrene is the most demanded material in modern construction. The raw material for its production is the same as for polystyrene - polystyrene, a styrene polymerisation product. But the technology of creation is completely different. In the manufacture of foam, this polymer is placed in a block mold and treated with steam. Its granules increase in size due to micropores and are sintered with each other.

But due to the formation of voids, this processing option greatly reduces the strength of the material.

Expanded polystyrene, depending on the production method, can be foamed (EPS) or extruded (XPS). In the first variant, polystyrene granules are filled with pentane, heated under the influence of steam, as a result of which their size increases tenfold. The balls are filled with air, becoming elastic, and then stick together.

The second type of material is produced by extrusion - by forcing molten polystyrene through a forming hole.

The structure of the polymer changes: strong molecular bonds are formed, which increases the density, moisture resistance and thermal insulation qualities. Such insulation is lightweight, frost-resistant, but fire hazardous, which is why fire retardants are added to the material - substances that accelerate attenuation.

Extruded expanded polystyrene due to the integral structure, consisting of closed granules filled with gas molecules, is more stable to the effects of the external environment and liquids. But the cost of this thermal insulation is 3 times higher than that of conventional foam.

In the production of expanded polystyrene boards, a large block is first obtained, which is then cut into standard sheets.

They can be of various thicknesses.

Advantages and disadvantages of the material

The advantages of expanded polystyrene can be attributed :

• low thermal conductivity;
• sound insulating qualities;
• moisture resistance;
• light weight;
• ease of processing (its can be easily cut with a saw or knife);
• ease of attachment;
• excellent adhesion to other materials;
• frost resistance (withstands up to -50 ° C);
• safety during work (expanded polystyrene does not smell, does not dust and does not emit poisonous fumes);
• preservation of material properties for a long time (about 50 years);
• resistance under high loads;
• no shrinkage;
• biological resistance (does not grow moldy).

Disadvantages of material:

• combustibility (special additives make it self-extinguishing);
• may emit harmful substances when ignited;
• low strength;
• hygroscopicity;
• inelasticity;
• instability to ultraviolet light.

Styrofoam grades

In accordance with According to the requirements of GOST 15588-86, foam polystyrene plates (PSB) are divided into two types, depending on the presence of a fire retardant in their composition:

• PSB-S - self-extinguishing,
• PSB - ordinary.

GOST 15588-86.

Expanded polystyrene plates. Technical conditions. File to download.

GOST 15588-86

According to the limit value of the density of the material PSB is additionally subdivided into grades: 15, 25, 35 and 50. The higher this parameter, the harder the plate and the greater the load she can endure.

For example, PSB-S-15 are used indoors, PSB-S-50 are suitable for industrial structures, including road construction. For insulation of foundations, the PSB-S 35 brand is most often used.

Calculation of the optimal thickness and amount of material

If it was decided to insulate the foundation of the house with expanded polystyrene, you first need to find out the optimal thickness of the material and its required amount.

The first step is to determine the purpose of the work:

• reduction of heat loss in the room;
• basement insulation;
• transformation of the basement into a living room.

The required thickness also depends on:

• climate;
• operation and purpose of the building;
• measures to protect against moisture condensation;
• energy saving.

The most important characteristic for a basement insulation is its thermal conductivity. The lower the value, the better the heat retains. The coefficient of thermal conductivity can be defined as the amount of thermal energy that passes through a material with an area of ​​1 m² if the temperature difference on the surface is 1 ° C. This value is measured in W / m² * ° C.To calculate the required thickness of the insulation, you need to know one more value - the resistance to heat transfer.

It is measured in m² * ° C / W. To calculate it, you can use the following formula: R = d / k, where d is the wall thickness, K is the thermal conductivity, and R is the required thickness of expanded polystyrene.

Table. Calculation of the thickness of the insulation.

Important! The correct calculation of thermal conductivity will help improve the efficiency of the heating system and save a lot of money. There is no need to buy plates that are too thick right away, as their cost is higher. It is more profitable to calculate the best option in advance.

The required amount of expanded polystyrene can be calculated by multiplying the height by the perimeter of the house and dividing the resulting value by it square. The final result will help you find out how much foam you need in the sheets.

For work, you will also need glue, the consumption of which depends on the manufacturer and is indicated on the package.

Penoplex prices

Penoplex

Vertical laying method

The vertical option is suitable both for houses that are still under construction and for those that are in operation. It is best used for a home under construction. This method consists of the following steps.

Step 1.

The surface must first be dug out, cleaned of soil, debris, including construction, mold, dust and greasy stains.

Step 2. Then it is leveled with cement mortar and a coating waterproofing is performed, without using solvent-based mastic. This is necessary in order to avoid wetting the foundation from groundwater.

Prices for bituminous mastic

Bituminous mastic

Step 3.

The contact adhesive is diluted and while it matures, mark the lower boundary of laying on the working surface. Plates can be buried a little.

Step 4. Glue is applied in stripes around the perimeter and in the center, after a minute the board must be pressed to the base and held in this position for several seconds. If necessary, align it and fix the next one by inserting it into the groove.

It is better to use a level to avoid distortions. If a second layer is needed, it is positioned to overlap the seams of the previous one. This arrangement of the boards contributes to better insulation.

Step 5. The part of the foundation that will remain underground is not strengthened in any way - then it will still be pressed down by the soil.

Step 6. After the glue has dried, the boards are fixed to the remaining surface using dowel-nails. They are hammered into the surface by 4 cm.

Video - The procedure for warming the foundation with expanded polystyrene

Horizontal method of laying

Horizontal insulation is used for a foundation of slab and tape type, for which foam polystyrene with a thickness of up to 10 is taken see

Step 1. First, the site is cleared from the ground, leveling the bottom, the last few centimeters are removed manually.

Step 2. The base is covered with sand, which must be tamped.

Step 3. Temporary formwork is made, which is poured with a layer of concrete without reinforcement.

Step 4.

Then, when it hardens, the slabs are laid.

Step 5. A thick film is placed on top as waterproofing, which is glued with tape.

Step 6. Formwork is made, then reinforcement is made and the foundation is poured.

Step 7. When the formwork hardens, it is removed and additional thermal insulation of the side walls is made.

Video - Monolithic slab foundation. Thermal insulation and waterproofing

Video - Monolithic slab - technology

Thermal insulation of the blind area

Soil insulation around a building is used to protect it (the soil) from heaving and to reduce the depth at which the foundation is laid. Expanded polystyrene prevents deformation.

This increases the reliability and durability of the base.

Surface insulation begins with vertical placement, after which the sand is poured back 15 cm below the ground. The formwork is carried out at a distance of about one meter from the wall, the bottom is leveled and compacted. After that, slabs, a waterproofing film are laid and concrete is poured.It needs to be leveled so that there is a slight slope to the outside.

If the concrete has frozen, the formwork is removed and the blind area is finished with stone or paving slabs.

Protection of boards from external influences

It is necessary to finish the basement not only for a decorative look, but also to protect expanded polystyrene from external influences. It is very important to protect the insulation from ultraviolet rays and damage from small animals.

In order to preserve the integrity of the insulation, you need to cover it with a reinforcing mesh or shields made of wood shavings. The mesh is also attached with a dowel.

Cement plaster is applied on top. Additional waterproofing components can be added to the solution, which will help prevent the material from getting wet. When the surface is dry, it can be painted or any cladding material can be attached.

Prices for facing materials

Siding

Video - Fastening the reinforcement mesh to the foam

If the building is on wet ground or the water table is very high - when the foundation is insulated drainage is required (this can be a perforated pipe laid on a crushed stone pillow). It is made around the perimeter and taken out to a specially designated place.

Insulation of the foundation using expanded polystyrene plates prevents freezing, helps to eliminate temperature extremes from several sides and prevent formation condensate. Thus, the humidity in the basement and on the basement is reduced, the microclimate is improved and money is saved on heating the room. The positive effects of thermal insulation also contribute to a longer building life. Expanded polystyrene can be used not only outside, but also indoors, it is easy to work with it, and its long service life allows it to remain the most popular in the market of thermal insulation materials.

Video - Insulation of the foundation outside with expanded polystyrene