Construction country house– this is the dream of many of us. But in order to provide the necessary conditions for favorable living conditions for the whole family in winter and summer, it is imperative to insulate the foundation of the house from the outside. Without thermal insulation, not only does the level of heat loss increase, but there is also a danger of destruction of the underground structures of the structure.
On a suburban area
Thanks to high-quality insulation of the foundation and basement, heat is retained in the room, the penetration of groundwater is prevented, and protection from low temperatures is also provided. In order to prevent exposure to aggressive environment on the foundation of the house, protective measures are carried out, and the most important of them is external thermal insulation.
Requirements for insulation
To obtain a high-quality result, it is not enough just to carry out all activities professionally.
Important factors are also right choice consumables and their high quality.
It is quite difficult to choose insulation that is optimally suited for a specific purpose, both in quality and financially. After all, today you can find many options for insulation in different price categories and from different manufacturers.
Do-it-yourself installation of extruded polystyrene foam on a plinth
Therefore, when choosing, you should pay special attention to the following qualities of the material:
- Low hygroscopicity. This parameter is very important, as it determines the degree of moisture absorption. At a high rate, the material will absorb moisture and as a result will collapse, which will lead to the destruction of the base itself.
- High strength. The thermal insulator must withstand heavy loads of underground compressive forces. For example, the impact of soil, which increases in volume when frozen.
- Low thermal conductivity. The thermal insulator must have a reduced thermal conductivity coefficient to ensure good thermal insulation.
- Long service life. The thermal insulator should have approximately the same service life as the building, because replacing it is a rather labor-intensive process.
Taking into account all these requirements, you can choose the most suitable material for insulating the outside of your house with your own hands.
Coating waterproofing and penoplex
Selecting a thermal insulator
To insulate the foundation of a house from the outside, it is important to select a material whose properties are most suitable for the building, taking into account all its features and the climatic conditions of the area. Today, the following are especially popular among many consumers:
- expanded polystyrene;
- liquid polyurethane foam;
- extruded polystyrene foam.
Expanded polystyrene
It is an improved version of polystyrene and its derivatives and is a gas-filled material. Widely used in various branches of construction and industry.
Penoplex installation
The main advantages are:
- Low degree of thermal conductivity. Allows you to keep the room warm. For example, a material 11 cm thick gives the same results as a two-meter brick wall.
- Waterproof. Moisture absorption is about 6%, which allows the material to be used in conditions high humidity without fear of deformation.
- Long service life. Withstands up to 60 cycles of operation in temperature conditions from -40 to +40 C.
- Insensitivity to biological effects. The material is not exposed to microorganisms, mold and fungi.
- Environmentally friendly. During production, substances that are harmless to human health and the environment are used, so expanded polystyrene is also used in the food industry.
- A light weight. Thanks to it, the insulation of facades becomes labor-intensive and does not take much time.
- Heat resistance. When ignited, fire-resistant types of polystyrene foam tend to self-extinguish.
- Soundproofing properties. This is especially important for owners of houses and apartments in noisy areas. The use of 3 cm thick polystyrene foam sheets for insulation can reduce noise by 25 dB.
- Vapor tightness. The indicator depends on the density and structure of the type of polystyrene foam. Varieties with low vapor permeability are similar in this indicator to certain types of wood: pine, oak.
- Chemical resistance. The substance is not subject to the aggressive effects of ethers and alcohols, but is destroyed under the influence of solvents.
- Resistance to mechanical stress. Mechanical strength during tension is approximately 20 MPa.
- Relatively low price, which increases the availability of the material for many consumers.
Wiring diagram
So, expanded polystyrene is perfect option for use for various purposes, especially for thermal insulation of foundations.
Liquid polyurethane foam
Liquid polyurethane foam is polymer insulation, which is widely used to obtain uniform insulation coating.
This is one of the few materials that are simultaneously a thermal insulation, vapor barrier and waterproofing layer. They allow you to significantly save money and labor costs when performing thermal insulation work.
In the context
Benefits liquid polyurethane foam are:
- Low degree of thermal conductivity. This allows you to significantly reduce heat loss.
- Long service life. The service life is more than 30 years.
- The ability to create a favorable microclimate in the room due to optimal thermal conductivity and sound insulation.
- Considerable strength. Due to its good density and strength, the material is able to withstand large mechanical loads without losing its performance properties.
- Absolute sealing, which is very important when performing any type of insulation work.
Liquid polyurethane foam
Thermal insulation of the foundation using liquid polymer can be carried out both from the inside and from the outside. For external use, additional protection from direct sunlight may be required.
Protection is carried out by applying liquid rubber or facade paint, which prevents loss of waterproofing properties and increases service life.
Extruded polystyrene foam
It is a relatively young type of polymer heat insulator and is produced by foaming raw materials during the extrusion process. Due to a number of advantages, the material has won the trust of many consumers and today is widely used in various fields construction.
Formwork for blind area
The advantages of the material are:
- low water permeability;
- low thermal conductivity;
- resistance to chemical attack from inorganic solvents;
- ability to withstand a wide range of temperature changes: from -50 to +75 C;
- long service life;
- a light weight.
Installation drawing
Extruded polystyrene foam is widely used for interior and external insulation buildings, roofs, is integral part sandwich panels, etc. One of the most common types is penoplex.
Insulating the foundation from the outside with penoplex is relevant and popular due to its excellent performance qualities. Such plates have increased strength and can withstand huge loads, providing excellent waterproofing and groundwater drainage.
Do-it-yourself thermal insulation of the foundation with penoplex allows you to solve several problems related to the construction of the foundation and equipment of the basement.
Foundation thermal insulation
Usage modern methods thermal insulation is of great importance, especially in areas with harsh climatic conditions. This prevents a significant portion of heat loss and freezing of soils, which increase in volume, which leads to a rise in their level.
Foundation insulation with polystyrene foam
Insulating the foundation of a house from the outside with polystyrene foam is an excellent option for improving the thermal insulation qualities of the base of the house and preventing freezing.
Expanded polystyrene is an improved type of foam. Its use is more profitable, and installation is easier.
The video describes in detail how to insulate the base of a residential building with your own hands.
The process works as follows:
- Preparing the base. This stage can be carried out both during the construction of the building and after its completion. To do this, you need to dig out the foundation, clean it of soil, debris, rust and grease.
- Selecting sheets. In this case, you need to pay attention to two factors: density and thickness. They mainly use sheets with fire retardant additives and a density of 35 kg/m3.
- Waterproofing. This will prevent the influence of groundwater and its penetration through the insulator layer.
- Fastening polystyrene sheets contact glue. You can attach two layers, but so that the panels of the second layer cover the joints of the first.
- Protection of insulation with a reinforcing mesh to avoid strong mechanical stress and the penetration of rodents. A layer of cement mortar can be applied to the protective mesh.
- Providing drainage. This step is considered mandatory when constructing a building on wet soils.
- Basement insulation. The base also needs to be insulated in the same way, followed by finishing. After the glue has dried, the panels are additionally secured with nails.
- Soil insulation. The event involves isolating the surrounding land with a blind area insulated with polystyrene foam slabs.
Insulating the foundation and blind area can significantly increase the temperature in the structure and protect the foundation from destruction.
Insulation of the foundation with liquid polyurethane foam
Considered quite effective way, which reduces heat loss by 20–25%.
The main difference is the method of application using a special spray installation.
To do this, two liquid components are mixed with each other, forming a thick foam. When applied, it increases in volume and hardens, forming a protective seamless layer with excellent thermal insulation and waterproofing properties. Optimal thickness application is considered to be 60 mm.
Wooden building
The polyurethane foam layer can be applied at a temperature not lower than +5 C. Surface preparation involves cleaning from contaminants, and surface quality is an unimportant factor.
As the foam hardens, it changes color. When performing work, various problems may arise related to equipment and neglect of weather conditions.
For example, when applied under conditions subzero temperature Cracks may appear that need to be repaired in the future, otherwise water may accumulate in them and freeze. After polymerization, the polyurethane foam layer has low plasticity.
Foundation insulation using EPS
As a rule, not all insulation materials are suitable for thermal insulation of the base. To choose the right material For this purpose, its service life must be taken into account: it must be as durable as the building itself.
Insulation with extruded polystyrene foam (EPS) is considered a more reliable method than, say, polystyrene foam, since this material is more durable and has excellent performance characteristics.
Blind area with trays
For this purpose, you need to purchase heat insulation boards and suitable glue for attaching them. After this, a number of preparatory activities should be carried out:
- Dig a trench around the foundation, digging into the ground.
- Apply EPS to the freezing depth of the ground.
- Clean the foundation from debris and dirt.
- Apply a special primer in two layers, wait for it to dry and absorb into the concrete.
- Provide waterproofing with bitumen mastic.
- Apply glue to the boards.
Attaching the slabs to the outer part of the foundation is allowed 1 minute after applying the glue. If the panels have a large area, you need to apply the glue in several strips using a comb spatula. If the slabs have locks, then a few days later the seams are sealed with polyurethane foam, and the slabs themselves are additionally secured with dowel nails.
Two-story mansion
How to insulate the foundation of a wooden house
Many owners wooden houses They believe that to ensure favorable living conditions, it is enough to insulate the walls and floor. However, this is not true, because serious heat loss can occur through a wooden floor - up to 20%. Therefore, thermal insulation of the foundation is mandatory, especially if the house is located in an area with harsh weather conditions.
Foundation insulation wooden house outside will not only create favorable conditions indoors, but also to prevent adverse effects on it. For this purpose, polystyrene foam and its varieties, as well as expanded clay, are usually used.
Stone finishing
Insulation of the foundation of PPS or EPS
Expanded polystyrene has excellent consumer properties, such as low thermal conductivity and moisture absorption, resistance to negative influences weather conditions, affordable cost, ease of installation, etc.
These and other characteristics have made this material one of the most relevant and in high demand among many consumers.
To insulate only the above-ground part of the foundation or plinth, a fairly simple installation is required. PPS sheets are simply attached to the surface using glue or special fasteners.
After this, cladding or plastering is performed. However, you should know that installing insulation does not mean complete waterproofing, so it should be carried out separately to avoid groundwater from penetrating under the floor.
At the summer cottage
If you have a basement, you should insulate not only the above-ground part of the base, but also the part that is underground.
In this case, it is necessary to completely waterproof the walls. For this purpose, a trench is dug around the wooden house, then the foundation is cleared of soil and debris. Next, EPS panels are attached to the surface, after which the whole thing is backfilled and compacted.
The insulated base can additionally be finished with brick or other types of cladding that can withstand adverse weather conditions.
Foundation insulation with expanded clay
Often wooden house insulated from the outside with expanded clay. However, it has increased moisture absorption.
To avoid the negative effects of this phenomenon, a trench is dug around the house and formwork with waterproofing is installed, after which the expanded clay itself is filled.
Blind area
This method is no less effective, but requires special attention and the need to adhere to all installation rules.
DIY insulation video
The video explains in detail how to insulate the foundation of a house yourself.
The foundation is the basis of any home; without it, no real house can be built. A properly designed and constructed foundation is one of mandatory conditions stability and durability of the entire building.
Even this reliable support is threatened by dangers - groundwater and soil freezing in winter, because of which the foundation of your house begins to collapse, and after it everything else risks collapsing. Insulating the foundation with polystyrene foam will effectively solve this problem and provide the house with long years life.
Many professionals optimal material for insulating the foundation, as well as the basement and the entire plinth, extruded polystyrene foam is called - durable, resistant to moisture and has minimal thermal conductivity.
Thanks to it, the structure will be reliably protected from dampness and frost, and the house will remain warm longer.
Not everyone clearly understands what polystyrene foam actually is. In general, this is nothing more than ordinary and well-known foam plastic, used in everyday practice, mainly for packaging fragile items. This is a durable, lightweight, heat-saving, biodegradable and almost insoluble material obtained by filling styrene granules with gas and then heating them.
When exposed to temperature, the granules “swell” until they occupy the entire volume available to them and sinter together.
Extrusion or has a special manufacturing technology. For ordinary polystyrene foam, polystyrene granules are simply heated with water vapor, while to obtain EPS, several processes are used at once: the granules are mixed and heated, a foaming agent is introduced, and then extruded under high pressure, i.e. pushed through the molding hole.
This technology provides greater uniformity and, therefore, greater strength of EPS compared to foam plastic.
Pros and cons of EPS Expanded polystyrene insulation at the lower level of the building confidently competes with more familiar mineral wool . The latter loses its effectiveness when wet, so it is not advisable to use it underground. Expanded polystyrene will absorb less than 1% of its total volume during a whole month of direct contact with water (for example, with groundwater that becomes active in the spring). In addition, this material does not rot and does not give in and is able to withstand up to a thousand freezes without deforming or losing its properties.
The main positive quality of extruded polystyrene foam, which is extremely important for thermal insulation of foundations - low thermal conductivity - is explained by its unique closed-porous structure. Expanded polystyrene is, in fact, a cluster of closed cells filled with gas. Together they form a kind of air cushion, which does not let out heat from the inside and does not let in cold from the outside. That is, EPS ideally meets the requirements that high-quality insulation must meet.
The density of expanded polystyrene significantly exceeds the “ceiling” required to insulate the basement and basement (up to 35 kilograms per cubic meter).
Finally, the clear benefits for consumers are:
- light weight of the material;
- ease of cutting;
- ease of installation, ensured by connecting tenons and grooves along the edges of the slabs;
- resulting from the previous point, the ideal joining of the plates, so that the cold will not penetrate between them.
Expanded polystyrene also has its negative sides. The main one is the flammability of the material. Treatment with a protective compound will help solve this problem.
When and in what order to insulate?
The foundation is insulated with extruded polystyrene foam both during the construction process and when the house is already ready. You don’t need to be a professional to do everything yourself - EPS processing methods do not require any special skills.
Thermal insulation of the basement floor requires strict adherence a certain order actions:
- foundation preparation;
- installation of waterproofing material;
- laying insulation;
- installation of a protective layer;
- final finishing of the base;
- backfilling the trench;
- installation of a blind area.
Preparation and waterproofing
The preparatory process has its own nuances for each type of foundation. "Tape" standard depth You should manually dig a trench up to one meter wide and to the freezing depth. No technique is used in this case, so as not to accidentally “injure” the foundation. The surface is cleaned and leveled - the protrusions are chipped off and cracks are sealed with cement.
Waterproofing
Then a waterproofing layer is applied: bitumen mastic using a roller or liquid rubber from a spray bottle. It is important that the waterproofing material is applied in a continuous layer and does not contain organic solvents that have a destructive effect on EPS.
Even more effective protection The strip foundation will be provided by a combination of bitumen and rolled material. Ruberoid, fiberglass, etc. are applied to the mastic in a heated state with an overlap of up to 150 mm, the joints are coated with bitumen. In the same way, a slab foundation can be insulated from moisture.
If the foundation is on stilts
With a pile foundation, a combination of a waterproofing compound and a drainage system is required to protect against groundwater. The drainage is installed in the following sequence:
- a shallow trench is dug;
- the bottom of the trench is covered with crushed stone;
- geotextiles are laid on top of the crushed stone;
- pipes for drainage of water are laid at an angle from the house;
- on top of the pipes there is another layer of geotextile;
- is placed upper layer crushed stone
Installation of EPS
When the waterproofing is finished and the bitumen has finally cooled down, insulation of the foundation with polystyrene foam proceeds to the main stage. The thickness of the insulation is determined in accordance with the parameters of the foundation and the climatic characteristics of the region. For example, if the winter in the area where you live is harsh and long, it would be reasonable to lay the thermal insulation in two layers, five centimeters each.
Foundation insulation with extruded polystyrene foam Expanded polystyrene sheets are available both corrugated and smooth. To ensure optimal adhesion to glue, the former are better suited. But if you nevertheless purchased smooth slabs, immediately before installation, treat them with a needle roller.
How to attach?
Fastening polystyrene foam below ground level requires the use of exclusively special glue that does not contain organic solvents. It is applied to the insulation with dotted strokes in the corners and in the center of the sheet. Then the insulation sheet should be firmly pressed against the foundation and held until the glue sets.
Under no circumstances should you fix the thermal insulation in the basement using dowels, as they will damage the moisture-resistant layer.
Above ground, the sheets are attached to the wall with hardware three days after installation, when the glue has completely dried. Each sheet contains approximately five dowels, which are driven into holes drilled through the insulating material.
How to lay it?
EPS sheets should be laid from the corner of the house, checking the correct installation using a level. At the corners, it would be better to lay the material in two layers, with a meter extending in each direction from the corner. The slabs are mounted to each other using a connecting locking system at the edges. If there are gaps between the sheets, they are sealed with polyurethane foam sealant.
Thermal insulation must be protected from rodents and unexpected ground movements. There are two main protective technologies: using geotextiles and roofing felt or reinforced fiberglass mesh. The cost of the glue on which the mesh is attached is quite impressive, so it is permissible to use it instead cement mortar.
Backfilling the trench
The trench dug around the perimeter of the house, after completing the insulation work, should be filled in only when all the materials are dry, including the cladding of the basement floor.
This process occurs in several stages:
- the bottom of the trench is covered with a layer of sand up to 150 mm thick;
- the sand should be moistened, leveled and compacted well;
- Expanded clay or gravel is laid on top of the sand layer, the layer thickness is from 200 to 300 mm;
- the excavated soil is poured on top of the gravel cushion and compacted very carefully;
- The trench should not be completely buried; approximately 300 mm should remain to the ground level for the blind area.
Installation of blind area
Insulation of the foundation cannot be considered complete without the final installation of the blind area. The latter is a narrow path along the perimeter of the building, concreted or covered with asphalt. Its width varies depending on the extension of the roof, the minimum is 600 mm. The sloping surface protects the foundation from rain and melt water flows. In addition, the blind area insulates the soil along the house, which is especially important for regions with cold climates.
Insulation of the blind area
During frosty winter and clay soil, prone to uneven freezing, for additional insulation It is advisable to equip the blind area with slabs of extruded polystyrene foam. The strength and elasticity of this material fully corresponds to the functions assigned to the blind area.
Work order
To install the blind area, you must first pour sand into the residual trench in a layer approximately 100 mm thick, compact it and cover it with roofing felt. Formwork made of wooden beam, into which the insulation is tightly packed. This is followed by a layer of waterproofing film (in in this case it is permissible to use polyethylene), a layer of fiberglass mesh and, finally, concrete or asphalt.
Nuances of insulation for different types of foundation
At slab foundation When used on soft soil, insulation of the base is possible only during the construction process.
Installation is carried out in the following sequence:
- sheets of thermal insulation material are attached to the foundation with glue in a checkerboard pattern;
- is laid polyethylene film(the overlap should be 150 mm), the joints are fastened with a special adhesive tape;
- a reinforcing metal frame is installed;
- concrete screed is poured.
When insulating pile foundation specially mounted outdoor wooden frame sheathed with polystyrene foam insulation with a thickness of at least five centimeters. The slabs are fixed with dowels, the joints are additionally reinforced with sealant. The appearance of the structure is not very aesthetic, so it involves finishing through decorative cladding.
Conclusion
High-quality thermal insulation of the foundation, especially in areas with an unfavorable climate, frequent precipitation, big amount groundwater and unstable soil should be one of the first concerns of a homeowner. With properly selected materials and carefully executed installation, foundation insulation will not only help you save money on heating your home, but will also significantly increase the “shelf life” of your home.
Basements account for about 20% of all heat losses in buildings. These losses can be reduced by thermal insulation of buried structures, which include foundations. High-quality insulation foundation with expanded polystyrene helps to avoid freezing of the material of the underground structure, condensation of steam on its walls, the appearance of dampness and the formation of mold in the basement or ground floor.
If the foundation was laid above the soil freezing mark, frost heaving forces appear under the base of the structure. At the same time, during the winter the surface of the earth can rise up to 35 cm, which often leads to deformation of the foundation. These risks can be minimized by horizontal thermal insulation of a buried structure by cutting off areas of frost heaving.
The above Negative consequences The cold is eliminated with the help of modern insulation materials, one of which is polystyrene foam. Under conditions of high loads and humidity under which the foundation is operated, this material is most optimally suited for its thermal insulation.
Expanded polystyrene has a homogeneous closed-cell structure. For this reason, unlike other insulation materials, it is not at risk of getting wet from ground moisture and subsequent expansion of its pores at low temperatures, leading to destruction of the material.
The insulation is produced in the form of slabs with a thickness of 10-120 mm. Many manufacturers equip them with L-shaped openings, which eliminate the appearance of so-called “cold bridges” at the joints of the elements of the thermal insulation coating. Compared to conventional polystyrene foam, the strength of polystyrene boards is much higher. Thanks to this, they serve as good protection for the waterproofing of the foundation, protecting it from mechanical and chemical processes that occur in the soil.
The light weight of the material and the ease of its processing make insulating the foundation with polystyrene foam from the outside an easy task even for a home craftsman.
The main criteria when choosing polystyrene foam boards are low thermal conductivity, water resistance and durability of the material.
Advantages and disadvantages of polystyrene foam insulation
The advantages and disadvantages of insulating structures buried in the ground with polystyrene foam boards largely depend on the operational properties and technical characteristics of this material. The most significant advantages of polystyrene foam insulation:
- In addition to performing its main function, thermal insulation coating reliably protects the waterproofing of the foundation from mechanical or chemical damage.
- When the foundation is insulated with polystyrene foam boards, the basement does not freeze and dampness does not appear in it.
- Thermal insulation increases the life of the house due to the material's resistance to temperature changes during the changing seasons.
- The cost of foundation insulation work is not high, since due to the low thermal conductivity of the products, slabs of significant thickness are not required for installation.
- Thermal insulation with polystyrene foam almost does not load the foundation due to its low weight.
- Foundation insulation with such slabs is considered quite reliable, since polystyrene foam is capable of operating in a wide temperature range from -50°C to +75°C. In addition, this material is not in demand among mice; it is chemically resistant and does not rot.
- The compressive strength of the insulation of 27 t/m2 allows the coating to withstand significant loads from the soil, foundation and overlying structures.
- Insulating the base of the foundation with expanded polystyrene reduces the impact of frost heaving of the soil on the structure.
Preparatory work before insulating the foundation
You can begin insulating the foundation of a house from the outside with expanded polystyrene immediately after its construction. However, if the building was built a long time ago, the process of thermal insulation of its underground part is more labor-intensive. In this case, the foundation will have to be dug up. To do this, a trench 1-1.5 m wide should be dug along the perimeter of the entire building, starting from its walls. The depth of the excavation should reach the base of the foundation.
After completing this work, the wall of the recessed structure, freed from soil, must be thoroughly cleaned of dirt with a brush with metal bristles and dried. Concrete sagging and protruding pieces of reinforcement revealed during inspection of the foundation surface must be removed using a grinder and a chisel.
All depressions should be sealed with cement mortar. If the unevenness on the surface is significant, a leveling layer must be applied to the foundation plaster mortar using during work metal profiles for lighthouses and the two-meter rule.
After the surface has dried, which will last about three weeks, the walls should be primed. For this you can use bitumen mastic. It can be purchased ready-made or obtained from molten bitumen with the addition of used automobile oil.
Before thermal insulation of the foundation, it is also necessary to prepare tools and Consumables. You will need a hammer drill and concrete drills, a mixer for mixing glue and cement mortar, regular and notched spatulas, a building level, a tape measure, assembly knife, hammer and plastic disc dowels.
In addition, you will need: insulation boards, glue for their installation, dry mixture for plaster and mesh for reinforcing the protective layer of the insulating coating.
Technology of foundation insulation with polystyrene foam slabs
It is recommended to insulate the underground part of the house and the basement only from the outside, since in this case the dew point, that is, the boundary of condensation of water vapor, does not shift to the side basement, but closer to the outer surface of the foundation. This prevents the formation of dampness in the basement and therefore the development of mold.
Work on insulating the foundation with extruded polystyrene foam is carried out in several stages in turn:
- Choice of insulation. In this case, it is necessary to take into account the thickness of the thermal insulation layer and its density. The thickness of polystyrene foam boards is 30-100 mm. If a more powerful coating is needed, the products must be attached to the structure in two layers. The density of expanded polystyrene suitable for insulation should be from 35 kg/m3. Its flammability class for the buried part of the structure does not matter, and for insulating the base it is preferable to choose a material containing fire-retardant additives.
- Waterproofing foundation walls. It is necessary in case of penetration of groundwater to the surface of the underground structure through the insulation layer. Waterproofing can be done roll materials and polymer-based bitumen mastic. Products containing organic solvents cannot be used for this purpose, since this insulation upon contact with them quickly becomes unusable, losing its thermal insulation properties. Rolled waterproofing materials are glued to the surface of the foundation using gas burner. To do this, you need to melt the back side of the insulating sheet, attach it to the foundation and smooth it out from the outside, removing air bubbles from under the material. The joints between the glued sheets should be coated with mastic.
- Installation of polystyrene foam boards on the foundation. It is made using acrylic glue, which should be applied in strips around the perimeter of each slab and in the center. After holding the product for a minute, it must be pressed firmly against the foundation. After a few minutes you can install the next slab. To ensure that there are no distortions at the joints of products, their installation should be carried out using a building level. If, according to calculations, the base requires a coating of greater thickness than the standard size of the slab allows, thermal insulation must be done in 2 layers. In this case, the arrangement of the slabs should be such that the next row covers the joints of the previous one. The gaps that may remain between the plates after their installation must be filled with polyurethane foam.
- Protection of the insulating layer. It is provided for by the technology of foundation insulation with polystyrene foam and is necessary in connection with difficult conditions thermal insulation work in the ground, since on its side the foundation is constantly exposed to mechanical, chemical and natural influences. To protect the insulation, a mesh with small cells is used. It is attached to the foundation along the perimeter of the building to the height of its underground part using dowels. Outside on the grid it is necessary to make plastering work, adding waterproofing substances to the cement mortar, which will play a role additional protection insulation against getting wet.
- Drainage device. It is recommended for houses located on soils with high level groundwater, and is designed to drain it from the foundation. Drainage system is a pipe with many holes made of metal or plastic. It is laid on a special crushed stone cushion around the perimeter of the house and covered with coarse-grained material on top to allow free access of groundwater to the holes drainage pipe. Water is drained into a well specially dug for this purpose, or into a natural depression - a ravine, ditch, etc.
- Backfilling the foundation. It should be done carefully with sand, expanded clay or soft soil to avoid mechanical damage to the protective layers of the surface of the underground structure.
- Base insulation. Outer part the foundation should also be insulated. The procedure for work is absolutely similar, with the exception that the insulation slabs of the above-ground part of the structure are additionally fixed with disc dowels, 4-6 pieces for each covering element. Holes for dowels can be made using a hammer drill or drill with an impact device. Thanks to the wide head and the material used, plastic fasteners hold perfectly polystyrene foam boards without creating “cold bridges”.
- Soil thermal insulation. It protects the foundation from destruction and helps to increase the temperature of the house. The principle of operation of thermal insulation is as follows: the backfill soil around the foundation is protected from low temperatures by making an insulated blind area, while the freezing zone moves away from the structure at a distance equal to the width of the insulation area. The insulating blind area is made of polystyrene foam boards and concrete. First, you should prepare a sand cushion for it; the resulting base must be thoroughly compacted. After this, it is necessary to assemble formwork 1 m wide from boards and bars around the perimeter of the foundation, lay polystyrene foam boards, a layer of waterproofing, reinforcement bars in it and fill it all concrete mixture. To ensure that rain or melt water does not linger on the blind area, when installing this structure it is worth considering slight slope from the building outwards.
- Base finishing. It is designed to protect the thermal insulation of the above-ground part of the foundation from mechanical influences and give it a beautiful appearance. After insulation and application of a protective layer of plaster to the base, this part can be painted or covered with any material intended for facing work.
You can protect your home from freezing during the cold season by insulating the foundation of the house from the outside with polystyrene foam or other types of materials. Without insulation, heat from the room will escape through the cooling walls.
Foundation insulation with polystyrene foam is a common method of thermal insulation of the base of a building. Expanded polystyrene materials have a foamed structure. Foundation walls protected by these thermal insulators retain heat well and virtually do not allow water to pass through.
Polystyrene foam is more cheap look polystyrene.
Insulating the foundation with extruded polystyrene foam will cost the most.
Polystyrenes are produced in the form of slabs of different thicknesses. You can choose the appropriate size of material taking into account the type of foundation of the house, the presence of a basement or basement. When choosing, you should also take into account the characteristics of the local climate.
In Russian conditions, it is considered more acceptable to insulate the foundation with polystyrene foam 5 cm thick. If a wine cellar is equipped in the basement of the premises, the temperature in which is about 10 ° C, then it will be better if the thickness of the polystyrene foam is 10 cm.
Increased attention is paid to gluing the corners of the foundation, since freezing of the entire structure begins precisely from them. For this purpose, slabs approximately 3-4 cm thicker than the main heat insulator are used.
In fact, not too many heat insulators are suitable for insulating the foundation. The choice is made according to the rule that the thermal insulation layer must have a service life approaching the durability of the structure itself. Based on this, we can conclude that it is better not to use polystyrene foam for insulating the foundation.
Considering that the service life of reinforced concrete is at least 100 years, and foam plastic is about 20-25 years, it is almost impossible to control the condition of PPS buried in the ground.
After using polystyrene foam, a problem will certainly arise associated with re-insulating the foundation. Despite the fact that thermal insulation with polystyrene foam is performed more often than insulating the foundation with polystyrene foam, this approach is not considered rational among professionals.
Properties of polymer insulation
IN modern construction For foundation insulation work, the most suitable polymer materials are used:
- penoplex;
- extruded polystyrene foam.
There are no fundamental differences between these polymer-type heat-insulating materials. This is explained by the fact that they are made on the basis of polystyrene. There are minor differences in the production technology of these heat insulators related to foaming. Penoplex and extruded polystyrene foam for the foundation have properties such as low thermal conductivity and high strength. These heat insulators are excellent for insulating the foundation of a cottage or private house. They can be used to provide insulation columnar foundation, shallow, strip, pile and other types.
The materials are similar in composition, which is reflected in their durability and quality. They do not absorb water, but polystyrene foam, which has lower thermal conductivity than polystyrene foam, is more durable.
The cost of expanded polystyrene is higher than that of polystyrene foam. Consequently, prices for insulation with these materials vary. These heat insulators have an attractive appearance. According to some information circulating among builders, foam plastic is considered a material that can replace 50 cm of brickwork. No one has carried out any experiments to compare the density of brick and foam plastic, but this indicator is lower for PPS, so the insulation has less thermal conductivity than brick.
Insulation of the foundation from the outside with polystyrene foam
Carrying out installation work for foundation insulation with polystyrene foam does not amount to special labor. Insulation should be applied to the waterproofing. Insulation of a strip foundation with polystyrene foam is carried out as follows:
- the wall is treated with a heat-insulating coating;
- the surface of the wall is covered with a waterproofing layer;
- measurements are taken of the freezing depth, to which 5-10 cm is added;
- the container (bucket) is filled 1/4 with water and foam glue is added;
- the composition is thoroughly mixed with a mixer until the consistency of thick sour cream;
- glue is applied to the foam sheet in several places and leveled using a notched trowel;
- the insulation sheet is pressed tightly against the foundation wall;
- the subsequent sheet is inserted into the lock of the previous one, if provided;
- the sheet is glued to the wall by pressing the material;
- the foam is covered with a PVC membrane;
- the dug trench is filled with sand.
All steps to insulate the foundation with foam plastic are not complicated. At the same time, experts do not recommend nailing the insulation to the foundation wall with nails, since you can break through the waterproofing.
The foam installation method is most suitable for beginners. This method cannot be compared in cost to spraying polyurethane foam. It is best to carry out insulation with an assistant, so that one person can cut and feed the sheets, and the second can apply glue and mount the insulation on the wall.
Application of thermal insulation in construction
The best method of thermal insulation of the base of a house is considered to be insulation of the foundation with penoplex. This method is used mainly at the stage of building a house. Fastening polystyrene foam to concrete in most cases involves the use of special bitumen mastic.
The entire surface is pre-leveled cement composition, and then the smooth foundation wall is cleaned. After this, the first layer of mastic is applied, that is, a bitumen primer, onto which the roll waterproofing, and a heat insulator is attached on top. An additional layer of geotextile is laid on top as protective coating. Often, penoplex is simply covered with soil.
Additional protection will not require significant costs Money, but geotextiles can significantly extend the useful life of the heat insulator. The technology of foundation insulation using expanded polystyrene can be studied by watching the video.
Another method of insulating the base of a house where there is no basement is used to insulate foundations in the form of a solid concrete slab.
The essence of the method is that polystyrene foam is laid on a sand cushion and poured on top concrete base. At the same time, it remains possible to immediately put into monolithic foundation heating circuit of the "warm floor" system. The name of this design is Swedish stove. It refers to shallow foundations, which are insulated not only from below, but also along the entire perimeter.
Based on the beliefs of energy efficiency, this development is one of the best, but it requires scrupulous work. Otherwise, failure to comply with the technology may lead to cracks in the slab and subsequent damage to the “warm floor” system.
The main disadvantage of the Swedish stove is the inability to carry out repairs after it cracks. A solid slab can be mounted on different soils, so it successfully replaces a strip foundation. Proper installation of the heat insulator should ensure a long service life of the base structure.
Insulating the structure of a Swedish stove is appropriate if the owner personal plot I decided to build my house from wood, planning to lay heated floors in the foundation of the building. This problem requires a serious approach, since after the house has already been built, it is impossible to do without dismantling work. In this case it is necessary to do:
- removal of plinth cladding;
- opening of the old blind area around the building.
If the foundation of the house is a shallow strip foundation, then you will have to dig a trench to its base in order to install heat-insulating material over the entire surface of the foundation. Another common option is to insulate the base and lay penoplex under the blind area. This will protect the underground part of the foundation from freezing.
Thermal insulation throughout the foundation and the soil under the blind area is the best way to insulate the foundation of a house. If you decide not to dig to the foundation, you can dig a hole that runs along the entire perimeter of the foundation. The width of the pit should be more than 1 m of the entire wall, and its depth should be 200-300 mm. The soil near the base must be compacted properly. Next you will need to do the following:
- clean the base;
- remove all sagging;
- seal cracks;
- dilute the glue in water;
- strengthen polystyrene boards to the base;
- fix the slabs with umbrella dowels;
- pour a layer of sand more than 10 cm wide into the hole;
- level and compact the sand;
- lay out slabs of penoplex (expanded polystyrene);
- strengthen geotextiles;
- refill the blind area;
- install the plinth cladding.
Choosing polystyrene foam for foundation insulation
Because the technological process The production of extruded polystyrene foam is carried out under pressure, this makes it possible to produce insulation, the structure of which includes molecular bonds of high strength. EPPS is of higher quality than polystyrene foam (PSB). Often, extruded polystyrene foam becomes a material that is almost irreplaceable in cases where ordinary foam plastic simply cannot withstand the load.
Before choosing EPS, you need to understand what technical characteristics it has. Expanded polystyrene is manufactured in several modifications, since different areas of the house (roof, walls, foundation) require different kinds PPP. Each modification of the teaching staff has different characteristics, therefore it can be used when insulating only a certain area of the house.
Markets building materials They sell polystyrene foam in 3 main brands:
- PSB-S-15.
- PSB-S-35.
For insulating the foundation, the last option is considered the most suitable, because this brand of heat insulator has protective sealed layers, so it does not absorb water. When purchasing expanded polystyrene, you should make sure that the material is marked with the “Foundation” mark. This will allow you to choose a material that is suitable for all technical characteristics.
The thickness of the EPS is selected depending on the climatic conditions in the region of construction. The width of this material can vary from 1 to 10 cm. For middle latitudes, a heat insulator 5 cm wide is suitable. Each manufacturer produces similar heat insulation boards various sizes, so you must first determine how much they will be needed.
Polystyrene can be strengthened to the foundation using either special glue or bitumen. It is worth considering: after gluing, polystyrene foam slabs remain movable for more than 20 minutes. Therefore, they need to be strengthened not only with glue, but also with plastic dowels, selected with a margin of length.
If polystyrene with a width of 5 cm is mounted, then the dowels must have a length of more than 10 cm. To attach the slabs, glue of the Bitumast brand, Ceresit ST-84, cement-polymer, bitumen adhesives that do not contain gasoline, ether and acetone are used.
Properties of extruded polystyrene foam
Many home owners use foam plastic to insulate the foundation, which is considered good thermal insulation material. Professionals believe that polystyrene foam is more suitable for thermal insulation of external walls than for insulating the foundation.
Foam plastic can be damaged by rodents, and its shelf life is not very long, since this heat insulator absorbs water, while having low strength and a very high deformation coefficient. Pressless expanded polystyrene (foam) begins to crumble into individual balls after just a few seasons. This occurs due to the hygroscopicity of the material.
Extruded polystyrene foam (EPS) is more durable than polystyrene foam. The duration of its operation significantly exceeds the shelf life of polystyrene foam. Builders often call EPPS Polpan. The technology for its production differs from the production process of polystyrene foam, since EPS is produced under pressure, initially representing a semi-liquid viscous foam mixture fed through a nozzle with a certain cross-section.
As a result, slabs of various sizes are produced. Modern developers often have to insulate the outside of houses with penoplex slabs, that is, extruded polystyrene foam. The material is orange in color.
Thermal insulation of a columnar foundation with polystyrene foam
Before you insulate a columnar foundation with your own hands, you will need to purchase a heat insulator and suitable glue for it. Then you should perform all the following types of operations in turn:
- Dig the foundation to its depth, making a trench around it.
- Cover the foundation with EPS at least to the depth of freezing of the soil.
- Clean the foundation, removing all crumbling or chipping concrete particles.
- Cover the surface of the foundation with a penetrating primer (2 layers) and let it dry until it is completely absorbed into the concrete.
- Waterproof the foundation with bitumen mastic.
- Apply glue onto the slab in spots.
The polystyrene foam is attached to the foundation 1 minute after applying the glue. If the size of the polystyrene board is 120x60 cm, you need to apply more than 8 strips of glue 1 cm wide. For this, a comb spatula is used. You need to start from the bottom, rising in rows.
If the polystyrene foam insulation does not have special locks, then after 3 days polystyrene foam is introduced into the seams between its plates for sealing. Dowels can be used for fastening, so holes for them are drilled along the edges of the slabs and in the center of each of them.
When insulating a columnar foundation with your own hands, coating waterproofing can be used if protection from capillary water is required. The level of hydrostatic pressure can reach up to 0.1 MPa.
The technique of coating waterproofing is quite simple. It is performed using bitumen or polymer mastics that cover the surface of the foundation with a film with waterproof properties. The use of coating technologies is typical for vertical waterproofing of foundations.
Carrying out horizontal coating waterproofing, it is necessary to take into account that due to their low strength they are used only as auxiliary waterproofing layers. After treating each hole with a small amount polyurethane foam dowel-nails are driven into them. Then waterproofing is applied to the heat insulator with polymer mastic, and after it dries, the trench is covered with earth.
Many owners, trying to insulate their house, forget that a significant part of the heat escapes through an uninsulated foundation.
It’s one thing if the floor is well insulated, but quite another if it’s not. Therefore, it is necessary to ensure thermal insulation of the base of the house - to protect the foundation from freezing.
Insulating the foundation allows you to solve two important problems:
- reduction of heat loss;
- protection of the foundation of the house from freezing and deformation. Let's clarify this point. Most of the soil in our country can be classified as heaving. It tends to freeze to a considerable depth, and during the process of thawing, change its original volume. When the soil plays, it has a detrimental effect on the foundation that is located on this soil.
For external insulation of the foundation, various thermal insulation materials can be used. But the most effective is the use of rigid insulation - polystyrene foam. And to be precise, one of its two types - polystyrene foam.
Insulating the foundation with foam plastic from the outside
Foam insulation can be considered the most popular method of foundation insulation. This is due to the characteristics of the material:
- cheapness;
- absolute non-hygroscopicity;
- durability. Important parameter, since insulating the foundation from the outside with polystyrene foam is a rather labor-intensive process;
- polystyrene foam does not deform or change its size under the influence of moisture or chemical compounds;
- resistance to any ambient temperature;
- the lowest thermal conductivity coefficient among known insulation materials. This is due to the structure of the material itself. After all, polystyrene foam is 98% air. Which is known to be a poor conductor of heat.
Basic physical and mechanical properties different brands polystyrene foam are presented in the table
The only significant disadvantage of polystyrene foam is its fragility. To minimize the appearance of cracks and damage, you need to quickly cover the area with an adhesive mixture.
Before proceeding with installation, please note that insulating the foundation with foam plastic from the outside is carried out only in the warm season. The foam itself can withstand low temperatures. But the time it takes to dry the base and the properties of the glue may change.
How to insulate a foundation with foam plastic
The sequence of work on insulating the foundation with foam plastic can be presented as follows:
1. Goal setting
That is, the decision for what purpose the insulation will be carried out. For example, reduce heat loss from a living space, insulate the basement under the house from the outside, or turn the basement into living room. Depending on this, the thickness of the foam for insulating the foundation will be selected.
2. Planning
2.1 Material selection
In this case, the insulation is polystyrene foam, and you can choose glue or adhesive foam as the adhesive composition.
Each foam adhesive has its own advantages and disadvantages. As well as different costs and setting times. Therefore, the budget and construction time have a direct impact on the choice.
2.2. Calculation of foam thickness for insulation
Before starting work, you need to determine what thickness of foam plastic will be sufficient to insulate the foundation in accordance with the goal.
The calculation can be carried out based on the data in the table below (parameters for polystyrene foam brand PSB-S-25).
For clarity, we present some signs. Foam plastic 50 mm thick. corresponds to the heat saving parameter with brickwork 250 mm thick. (one brick).
It is worth noting that when planning to convert a basement into a living space, you need to not only insulate the foundation, but also the basement and the ground floors.
2.3 Calculation of the amount of foam for insulation
You can determine the amount of material by multiplying the height of the cladding (foam sheet) by the perimeter of the house. And dividing by 0.5 (the area of one sheet.) The resulting result will reflect the required amount of foam in the sheets. The amount of adhesive composition depends on its type and consumption. Which is indicated by the manufacturer on the packaging.
2.4. Budgeting
Even if you do not pay builders, but insulate the foundation yourself, you will inevitably incur some costs. Drawing up an estimate will allow you to understand what budget will be sufficient for the planned work. It must include: the costs of purchasing materials, their delivery, and removal of construction waste.
3. Choosing foam for foundation insulation
When purchasing polystyrene foam, pay attention not only to its density, but also to the geometry of the sheet. The permissible deviation in the length and width of the foam is 10 mm. Otherwise, you will have to adjust each sheet on site, which is not very convenient. Well-known manufacturers ensure that this parameter is observed, but the “shrubs” can make any cutting. Accordingly, both the quality and durability of such foam should raise doubts.
The second aspect that allows you to determine the suitability of polystyrene foam for insulation is its color. The color of high-quality foam is snowy white. If it has a yellowish or grayish tint, we can conclude that low-quality raw materials were used or there were violations in technology. But, most likely, such material was exposed to ultraviolet radiation as a result of improper storage. That is, its surface layer is destroyed under the influence of the sun. Such insulation can be used, but provided that the depth of the damage is not great, and the damaged area is treated with a foam grater.
4. Excavation of the foundation
It is advisable to insulate the foundation at the construction stage of the building. This way the work is easier to complete because it is not duplicated. Modern developers do just that.
But what about those whose house was built several decades ago? In this case, you have to dig out the foundation almost to the ground. Ideally, to the depth of soil freezing in a given region (usually 1-1.5 m). Or at least the length of a sheet of foam plastic. That is, about half a meter.
In this case, the width of the trench is determined by adding the thickness of the sheet and the space required for the work. That is, it should be 350-500 mm. Making it wider is impractical, especially if you are insulating the foundation with polystyrene foam yourself, without using construction equipment, and a narrower trench will be inconvenient for work.
When choosing soil from a trench, you should think about where to put it. Insulation work lasts more than one day, and the sale of excavated earth should not affect movement around the site.
5. Filling a trench near the foundation
The bottom of the trench, or at least that part of it where the foam plastic will be laid (50-100 mm), must be covered with sand. Layer thickness is about 200 mm. The sand must be compacted, maintaining a slight slope. This will allow the water to flow away from the foundation. If the groundwater level is high, you need to take care of drainage around the house - pour a gravel bed, lay geotexile on it, and wrap the pipes in it.
6. Preparing the foundation base
The excavated foundation should dry well. That is why it is better to carry out work in the warm season.
Taking this opportunity (while the foundation is being dug), it is worth paying attention to the utilities that are inspected, isolated, repaired or restored.
Next, all delaminations are removed from the foundation, and unevenness is leveled - this will prevent the appearance of voids. Then a level is struck; this line will serve as a guide to the height of the foam sheet.
Moisture-proof mastic or bitumen mastic is applied to the prepared foundation. Its purpose is to protect the foundation from moisture.
As for bitumen mastic, there is a controversial situation; according to the laws of chemistry, bitumen (based on solvents) has a detrimental effect on the structure of the foam. At the same time, there is practical evidence that the foundations of private houses, treated with bitumen and insulated with foam plastic, last for many years. Probably, everything depends on the chemical composition of a certain bitumen mastic and the method of fixing the foam.
7. Attaching foam plastic to concrete (foundation)
Installation of polystyrene foam is carried out using an adhesive solution or adhesive foam.
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The adhesive solution is applied in blots or with a notched trowel to reduce the possible gap between the sheet and the base.
Advice. If you choose glue for foam plastic, it is better to take foam in cylinders under the gun, this way it is more convenient to use and costs less.
During installation, the sheets are laid at a minimum distance from each other.
If there are two rows, the sheets in them should be arranged in a checkerboard pattern. The sheets are laid on a sand cushion and leveled.
Advice. If you need to achieve a sheet thickness of 100 mm. use two 50 mm sheets. The overlap between the rows will prevent the appearance of cold bridges. Work on installing the next layer can begin only after the glue in the previous one has completely dried.
The reinforced mesh is designed to protect the foam from mechanical damage if the insulation protrudes beyond the trench and may be damaged.
The mesh is applied to the top of the sheet and fixed with adhesive.
9. Finishing
If the house is with low base, i.e. the foundation of the building is flush with the ground and the foam is completely covered with soil, then installation of the mesh and finishing are naturally not needed. In this case, it is enough to fill the trench with expanded clay; it will serve as additional insulation, sand or soil.
Insulating the foundation with foam plastic from the inside
Internal insulation is carried out using a similar technology, excluding trench digging. But it has a number of features.
- mandatory fastening to an umbrella dowel (fungus). The dowel is attached to the corners of the sheet and one in the center;
- insulation is carried out along the floor (if it is planned to adapt the basement into a living space). In this case, polystyrene foam is placed between the joists;
- the need to use a membrane that will protect the base of the foundation from moisture;
- mandatory ventilation device, through a system of ventilation ducts, through through hole in the foundation or forced. Otherwise, moisture will accumulate in the basement, which will ultimately lead to the destruction of the foundation base, the appearance of mold and rot.
In general, insulating the foundation with foam plastic with your own hands does not require special knowledge and tools, but will entail time and physical costs.
