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We warm the house with foam plastic from the outside with our own hands. How to properly insulate walls with foam plastic from the outside - a step-by-step guide External insulation of houses with foam plastic

Good external insulation significantly reduces heating costs as well as Maintenance at home. However, warming a house in this way will only be effective if it is well done. Before proceeding to repair work, you should study well the question of how to isolate the walls from the outside. Then the funds invested in labor and materials will be effectively used and quickly returned in the form of savings on heating.

How to properly insulate the house with foam plastic from the outside, how to avoid mistakes?

Insulating walls with Styrofoam (a type of Styrofoam) is not a very difficult task, but you must follow certain rules. Mistakes made when performing insulation can result in it being less effective, and in some cases can lead to serious damage to the facade. To properly insulate walls, it is important to follow certain rules and avoid common mistakes. Below are the 11 most common rules and mistakes when insulating a building with Styrofoam.

  1. Proper wall surface preparation

The surface on which the polystyrene boards will be placed must be properly reinforced, stable, level and dry. It must be free of contaminants that reduce adhesion, such as:

  • dirt;
  • adhesive coatings;
  • formwork oil;
  • any kind of pollution caused by chemical or biological agents.

The base must be even - small inequalities (up to 2 cm) are leveled with a leveling mortar. In case of large irregularities (greater than 2 cm), you must use different thicknesses of the Styrofoam boards so that they form one plane.

Underlay related errors include:

  • incorrect assessment of the state of the substrate;
  • lack of primer;
  • poor assessment of the geometry of the walls (evenness, deviation from the vertical).
  1. Styrofoam bonding, insufficient adhesive

The adhesive must be applied both along the edge of the slab and on its surface. If you apply glue only along the edge, or only at one point, the plate will bend, and the edges of the plates will be visible on the finished facade.

Proper application of styrofoam adhesive:

a) along the periphery and points - in this case, the glue should be applied in the form of strips along the edge of the boards with a width of 4-6 cm. On the rest of the surface, the glue is applied pointwise, there will be from 3 to 8 points. The total area of ​​\u200b\u200bglue should cover 40% of the panels white color and 60% graphite plates.

b) the comb method, which is used only in the case of even, plastered surfaces. The adhesive is applied with a notched trowel over the entire surface of the board.

Note: The adhesive solution is applied to the surface of the polystyrene plate, and never applied to the substrate.

The adhesive on each sheet must be placed around the edge and on the surface.

  1. Adhesive selection

A poor choice of adhesive or poor quality mortar can cause the foam plates to come off, along with other layers of the façade. As a rule, it is recommended to use a complete insulation system from the manufacturer - such a system contains all the necessary elements, guaranteed quality, and good matching of elements with each other.

  1. Distribution of panels on the wall

It is important that the foam plates are offset by half their length from bottom to top, starting at the corner of the wall.


It is also important to correctly position the plates in the corners. If this is done incorrectly, then thermal bridges appear on the connection of the plates, through which heat losses occur.


In addition, polystyrene panels must also be laid neatly and tightly side by side. Connections must not form straight lines.

  1. Filling gaps between tiles

The gaps between the styrofoam boards must not be filled with adhesive solution (thermal bridges will occur). To fill gaps up to 4 mm wide, use polyurethane foam.

  1. Reinforcing with dowels

Dowels of insufficient depth will cause problems. If they are installed too deep, they will destroy the structure of the thermal insulation board. If they are installed too shallow, they can create a bulge that will be visible on the wall surface.


  1. Starter plinth and mesh

If a starter skirting and mesh are not used, the insulation will be exposed to the weather and to rodents such as mice, which often burrow into the bottom layer of insulation while looking for winter shelter and cause damage.


  1. Uneven foam board surfaces

The surface of the plates after their placement must be even. If there are irregularities, the surface must be sanded to eliminate the irregularities. Otherwise, they will also appear on the facade. Unfortunately, sanding polystyrene is a laborious and time consuming process, so it is often forgotten.


  1. The location of the plates around the door and window openings

At the corners of windows and doorways there should be no seams of board joints. In addition, in these places you should use additional diagonal grid strips.



Laying scheme in the corners of window and door openings

The corners of window and door openings must fall into the central part of the polystyrene plate.

  1. Weather conditions and performance of work in inappropriate weather

Often installers do not take weather conditions into account during repairs. It is important that the insulation work is carried out in the appropriate weather - the temperature is not lower than 5 °C and not higher than 25 °C. Of course, at the time of warming there should be no precipitation. This is important, not for comfortable work, but for the properties of materials that retain their qualities only under certain conditions. For example, at a higher temperature, the adhesive will dry quickly before it can properly bond the foam to the substrate.

  1. Lack of sun protection materials

The use of solar shading is especially important when laying gray foam. Under the influence of the sun, it heats up quickly, and the result can be the formation of gaps between the plates and their peeling from the substrate.

How to properly insulate a house - video

Insulating the walls with foam plastic will help not only reduce heat loss, but also prepare the walls for decorative finishing. It is quite possible to insulate the walls with polystyrene foam with your own hands, the main thing is to follow the technology.

Foam insulation is made with outside walls. In this case, foam plastic plates, or expanded polystyrene are used - this is the same foam plastic, made according to more modern technologies. The advantages of this method include low thermal conductivity of the insulating layer, ease of implementation, moisture resistance of the material, and good soundproofing properties.

To make an insulating layer, you will need:

  1. Styrofoam (expanded polystyrene) slabs in an amount equal to the area external walls except for windows. The thickness of the plates is determined thermotechnical calculation, in any case, it should be such that the dew point is shifted into the outer insulation layer. If the thickness turned out to be non-standard, then the foam is attached to the walls in two layers, and the second layer is glued only after the glue has completely dried on the first layer.
  2. Mineral plates. They are placed for fire protection purposes around all windows, doorways, as well as between floors with a high building height. The thickness of the plates must match the thickness of the foam. Plates must be selected with a high density index. The number of them depends on the number of windows.
  3. Reinforcing mesh for external works.
  4. Primer for walls. Primer consumption depends on the material of the walls - porous materials must be coated in two layers.
  5. Adhesive for external works for fixing foam and reinforcing mesh. Sold as a dry mix.
  6. Perforated metal corner: for making the starting bar - equal in width to the insulation layer, as well as a smaller width to strengthen the corners.
  7. Tool: perforator with a drill Ø10 mm, the length of the drill is equal to the thickness of the insulation plus 7-8 cm; construction mixer; level; stationery knife.

Styrofoam wall insulation technology

Before starting work, you need to plan the time so as not to leave a layer of fixed foam plastic not covered with plaster on the walls for more than 5-7 days. Sunlight destroys polystyrene foam very quickly - it turns yellow, surface layers begin to destructure, and the insulation loses some of its thermal insulation properties.

  1. Wall preparation. The walls are cleaned with a brush from dust and dirt, if necessary, repair and level. Wall differences should not be more than 2 cm along the length of the foam sheet. If the walls are covered with paint or plaster, all poorly fixed areas are peeled off.
  2. Prepare the primer. If the primer is sold as a concentrate, dilute it according to the instructions on the package.
  3. Apply the primer to the walls with a brush or roller. The primer sometimes has to be applied in several layers. You can check the quality of the dried primer as follows: run your hand along the wall, while there should not be significant traces of sand on your hand, building dust or residues of coloring compounds.
  4. Set the starting bar on the basement of the building using a level. The starting bar is necessary to maintain the insulation layer during the drying of the glue. If the height of the building is small, you can do without it, while the first sheets of foam from the bottom must be fixed until the glue is completely dry.
  1. The plank is fixed around the entire perimeter of the building with dowels, at least three dowels per meter of length.
  2. Dilute the glue according to the instructions on the package, for this, pour the dry mixture into a pre-prepared clean cold water. The size of the container must be sufficient for mixing.
  3. Stir the glue with a construction mixer, leave to mature for 5 minutes and mix again. After that, the glue is ready to go.
  4. Apply glue to the polystyrene boards with a spatula. It is possible to evenly distribute glue over the slab only in the case of even walls.

  1. For brick or block masonry, which is characterized by irregularities, it is applied in a strip along the perimeter of the slab and with several blotches in the center.
  2. The plate is placed on the starting bar and pressed tightly against the wall, making sure that there are no distortions.
  3. Check the leveling of the plate in all three directions. If necessary, level with light taps on the plate, with a hand or a hammer through a wooden block.
  4. Lay the boards in a horizontal row. The next row is placed in a checkerboard pattern, forming a dressing, as when laying brick walls.

  1. In the process of laying the foam, if necessary, cut to size with a knife. Care must be taken not to leave large gaps.
  2. Around window and door openings, a 20-centimeter layer of non-combustible insulation must be laid. Basalt mats or mineral slabs can be used as it, the density of the slabs must be such that they can withstand plaster without deformation and top coat. If the building is high, a layer of non-combustible insulation is also laid every 2-3 floors.
  3. Mineral plates are fixed similarly to foam plastic on glue, applying it over the entire surface.
  4. After gluing, if necessary, you can cover with glue all the cracks between the insulation and window block, as well as joints of insulation and foam.

  1. The glue dries within 1-2 days. After that, you need to fix the insulation. To do this, use a puncher and a pair of dowel-nail. There should be at least 4-5 dowels in one plate. To reduce the number of holes, it is allowed to drill holes in the joints of the plates, thereby pressing two or three adjacent plates.
  2. Holes in the plates are drilled so that the dowel enters the wall by 5-6 cm, the length of the drill is calculated accordingly as the width of the insulation plus 7-8 cm.
  3. For fastening the foam, special plastic dowels-fungi with a wide cap are used. They do not form cold bridges, securely fix the stove and do not protrude above its surface. They are hammered in with a hammer, after which they are finished off with a nail.
  4. All corners are reinforced with a perforated corner, which is attached to the adhesive for insulation.

  1. Styrofoam should not be left in the sun for more than a few days, therefore, after fixing the plates, they proceed to finishing work. The gaps between the insulation boards must be foamed. To fix the reinforcing mesh, a layer of glue is applied to the wall surface, the area of ​​\u200b\u200bthe site is chosen so as to have time to put and level reinforcing mesh until the glue sets. The reinforcing mesh must be taken for external work, since the mesh for internal work is destroyed over time when exposed to cement-based glue.
  2. Apply the reinforcing mesh to the wall, while 5 cm along the edge of the mesh should remain to form an overlap. It is more convenient to fasten the grid from top to bottom, slowly unwinding the roll.
  3. The mesh is pressed tightly against the wall, and the glue that has protruded above its surface is smoothed with a wide spatula. You can add more glue if needed. The grid should not protrude above the adhesive surface, but its contours should be traced. The next section is processed in the same way, not forgetting the necessary overlap of the mesh with a width of 5 cm.
  4. After the glue dries, after 2-3 days, the wall surface is rubbed with sandpaper, leveling if necessary, and proceed to the finishing.

The final stage - finishing

Wall insulation with styrofoam correct execution allows you to save up to 40% of energy resources for heating your home. At the same time, the foam is not subject to decay, resistant to fungus, does not deform from temperature changes, which allows the house to maintain a decent appearance for decades.

The idea of ​​insulating a building with the help of a hinged sheet heat insulator is so obvious and unpretentious in fact that often the building owners simply sheathe the building with expanded polystyrene foam without even thinking about the possible results of their creativity. Styrofoam insulation of external walls does not require huge capital investments, special training or knowledge. Nevertheless, there are more than enough problems and nuances in this matter, therefore, before insulating the walls with foam plastic from the outside, it will be useful to figure out and find out for yourself how to properly apply a layer of thermal insulation.

How is foam insulation different from other materials?

When choosing materials for insulating external walls, a dilemma almost always arises - the better to insulate a house:

  • polyurethane foam;
  • Sheet extruded polystyrene foam;
  • Mineral wool, fiberglass;
  • Backfill thermal insulation;
  • Foam panels.

The choice is not as obvious as it might seem at first glance. Mineral wool guarantees a very good coefficient of thermal conductivity, does not rot or decompose under the action of ultraviolet radiation, and most importantly, it is an absolutely fire-resistant material. Backfill materials generally cost a penny and do not require any preparation at all. EPPS gives the best thermal conductivity, which means it allows you to make the insulation layer much thinner, does not absorb water, condensate and even water vapor.

If we make a deeper comparison, then in fact the insulation of the walls of the house with polystyrene foam can be called the most optimal solution, both in terms of technology, and in terms of operation and durability.

Primarily:

  • Styrofoam has a thermal conductivity coefficient only a few percent higher than that of XPS. Despite the fact that the foam sheet is much cheaper than the advertised extruded PPS;
  • Unlike mineral fibers, foam sheets do not absorb moisture, do not sag on the mount and do not create additional load on the walls of the house. There is no need to talk about filling glass granulate or expanded clay - it can be used to insulate external walls during the construction phase;
  • It is enough to simply protect thermal insulation with a layer of facade plaster, decorative cladding made of tiles and siding panels.

It is clear that if it is required to provide the highest resistance to fire, then it will be preferable to use plastering of the outer walls. The same method turns out to be the least expensive and durable, it is not afraid of showers, frost and heavy wind.

Material for insulation of external walls

Styrofoam foam is different. Not and not any foam sheet is suitable for arranging wall insulation. For the purposes of external wall insulation, only PSB and PTT foams are used. The brands differ in density and the presence of a protective film. The numerical index in the designation of the foam brand indicates the density of the material.

The lightest, 10-20 kg / m 3 are used to insulate refrigeration chambers, trailers, change houses, balconies, windows, water pipes and containers. These are very light and not the most durable foam sheets, but at the same time they have the best thermal insulation. Sometimes they are used as thermal insulation under siding. For applying facade plaster, such foam is quite fragile. It happens that the high porosity of the foam plastic led to flooding of its surface under the freshly laid plaster. At temperatures below zero, the top layer came off along with the outer trim.

More suitable brands of foam for wall insulation from the outside are considered options with a density of 25 kg / m 3. Such a plate has sufficient strength to hold a layer of plaster mass, and at the same time provides high level thermal insulation of external walls.

In addition to the numerical designation of density, the marking contains an alphabetic index indicating the design features of the foam board:

  • A - a simple foam board without any design features. In fact, it is the cheapest, most common and available material used for insulation of any walls and surfaces;
  • B - slab foam material with an edge trimmed with a ledge. In this case, insulation of the house with foam plastic from the outside can be done with little or no cold bridges;
  • P - foam plates with a melted surface due to cutting the material with a red-hot knife-wire;
  • F - shaped foam plastic with a non-standard surface shape;
  • H - a special form designed for insulation of external surfaces.

Of course, the use of a material with a special edge configuration or with a protective layer knurled with corrugation for better adhesion to the plaster mass provides many advantages, but this does not mean that the insulation of external walls cannot be made from simpler "A" foam.

Note! Excellent machinability, especially of high-density foam grades, allows you to cut edges or even melt, if necessary, the surface of the plate material when insulating walls with foam plastic from the outside with your own hands.

It will be enough to assemble with your own hands a simple knife-cutter made of nichrome wire and a durable fiberglass frame. As a step-down transformer, you can use LATR or Charger. Such a device will help to insulate the outer walls without gaps and at the same time save on buying cheaper foam.

The last question about foam, which often stops homeowners from insulating the exterior and interior walls of the house, is related to the possible release of styrene and toxic decomposition products of expanded polystyrene. Experts authoritatively argue that both factors depend on the quality of the material.

Chinese foam plastic cannot even be stored in a residential area, at the same time, high-quality expanded polystyrene foam is used for stucco molding, home sculpture, insulation of walls, floors, ceilings with virtually no external cladding. Moreover, all standards modern materials for wall insulation, manufacturers are required to impregnate with flame retardants at the manufacturing stage. Such a heater under the action of an open flame and high temperature melts but does not burn. On external walls it can be used even without sealing with plaster mass.

Two words about possible insulation schemes

The only significant drawback, which would-be masters sometimes forget, is the low permeability of the material to water vapor. In the construction business, there is an “iron” rule: - each subsequent layer exterior finish walls should have a higher vapor permeability than those inside.

For relatively thin layers of insulation, with a thickness of foam sheets of 35-50 mm and a density of 15-20 kg / m 3, the problem is not so significant. Since light foam grades without surface melting have characteristics that are only 10-15% lower than those of red brick. In this sense, foam is much more convenient than EPPS, which generally does not conduct steam and water. That is, when insulating, a special ventilation gap or air between outer wall and a layer of foam. To arrange the insulation of the outer surface of the walls, the plates can simply be glued to the wall, like ceramic tiles.

Another thing is if, according to climatic conditions, the thickness of the insulation should reach almost 100 mm, and it is required to use heavier grades of foam. In this case, the technology for insulating walls with foam from the outside is somewhat different. Sheets of foamed material are laid on the walls like XPS on a mounted frame made of galvanized profile with fastening on fungal dowels. It is best that the underside of the foam sheet has a profiled surface in the form of alternating grooves or dots. Thus, most of the water vapor is removed.

Do-it-yourself insulation technology for external walls

The procedure for insulating walls is somewhat similar to laying facing tiles, with the only difference being that instead of ceramics or plastic, huge foam slabs are used. Do-it-yourself insulation technology with foam plastic on the outside of the building before starting work will require a small amount of preparatory work:

  • Any cladding and plaster of the exterior walls of the house is removed;
  • The plane of the walls is cleaned first by mechanical and then by manual grinding in order to remove the slightest bumps and external defects. The walls should be as smooth and flat as possible;
  • Caverns are closed up cement mortar and carefully polished.

After cleaning, the surface of the outer walls is treated with a primer deep penetration. All preparation of external walls for laying insulation should be carried out at a positive air temperature in dry, calm weather.

Laying foam sheets on the walls of the building

Styrofoam purchased in advance is folded outside under a canopy or covered with a tarpaulin, awning or any other material, the main thing is that the foam is not stored in the sun. Even scattered ultraviolet light after a few weeks of storage can make the edges and ends of the foam crumble.

Laying begins with a batch of adhesive mass. Usually, Ceresit CT85 or a similar adhesive for polystyrene foam boards is used for the cool fixing method. The mixture is added to a container with a measured amount of water and kneaded with a mixing nozzle with an electric drill. While the adhesive mixture is gaining water, it is 10-15 minutes, you can get down to business and pull it along the bottom edge outer wall marking cord. Support bars are usually laid out along the cord so that the first row of foam can be kept from slipping.

Sometimes, instead of a cord, they put a starting profile, similar to what is used for a frame for siding, in which case all the work on fixing the starting bar will need to be done in advance, a day earlier.

Next, we select the required number of sheets according to the markup for laying the first row of insulation on the walls. If the foam is planned to be laid with a mating edge, it can be cut here, based on the dimensions and markings.

Note! Usually craftsmen do not like to mess around with cutting edges, as it takes a lot of time, plus the edge of the sheet sometimes breaks or pricks.

If you do the insulation with your own hands, as they say, “for yourself”, then it is better to do an edge overlap, this will reduce the negative effect of large gaps at the joints. Glue is applied to each sheet with a spatula in the form of small blotches, 6-7 cm in diameter. A small amount of “sausage” glue is laid out along the edge of the foam. The layer thickness is 5-7 mm. If there are protruding reinforcement or irreparable defects more than 10 mm high on the walls, then most of the glue must be applied to the wall, only the edge zones are laid out on the sheet.

The sheet applied to the outer surface of the wall is gently, but slightly pressed down so that the glue comes out evenly around the entire perimeter of the material. Part of the adhesive mass will be squeezed out through the joints, this improves the adhesion and rigidity of the laid insulation, but it is not at all necessary to try to cover all the gaps with glue.

At this stage, it is important to lay the insulation as evenly as possible, without humps or holes. If the walls are curved, sometimes you have to cut and scrape the wrong side of the foam to get a surface condition close to flat. Otherwise, you will need to lay additional tens of kilograms of plaster to hide the curved walls with insulation.

Mechanical fastening of foam insulation

The adhesive itself is only capable of holding lightweight foam sheets to exterior walls, so additional fixation with mushroom fasteners is mandatory. Dowels with a plastic cap are hammered evenly over the entire area of ​​\u200b\u200bthe sheet. You can grab the edges of two adjacent pieces of foam with one hat.

After pasting the outer walls of the house with foam plastic, you must wait at least a week before proceeding to stuffing fungal fasteners for insulation. During this time, the mineral adhesive usually settles and gains at least 40% strength, so that drilling and driving dowels should not rip off the foam sheet.

If it is hot outside, then the foam insulation is covered with an opaque film or mesh for the duration of the setting of the adhesive base. Particularly picky craftsmen at this time cover up the joints and cut the edges of the foam.

The fungus installation technology is as follows:

  • According to the marking, drilling is performed at the point of installation of the fungus in diameter 0.2-0.5 mm less than the diameter of the plastic dowel;
  • A chamfer 10-15 mm deep is carefully cut along the edges of the hole, the fungus is hammered with a hammer through a wooden nozzle so that the hat sits below the outer plane of the foam insulation;
  • A steel rod is hammered into the central hole, wedging the fungus in the wall.

5-8 fungi beat on one sheet of foam. It is believed that the less metal in the wall, the more efficient insulation, therefore branded materials for insulation are made of plastic, including the central rods. But if you don’t know how to hit a plastic wedge correctly, but it’s better to buy with a steel nail, this will not affect the quality of the insulation, but it will keep it “tightly”.

For fixing in the wall, a hole 5-6 cm deep is enough. One centimeter is thrown over the glue gap, the rest is the thickness of the insulation. As a result, for a plate with a thickness of 50 mm, a fungus 10 cm long and a hole 11-12 cm from the foam surface will be required. If, after driving the wedging nails, part of the rod remains above the insulation plane, this is not a problem, it can be bitten off with wire cutters or powerful side cutters, the main thing is that the fungus settles completely and is firmly wedged in the wall.

Additional sediment foam insulation usually leads to a weakening of the joints between the foam boards, that is, the seams may increase slightly in size. After driving the fungi, the joints are cleaned and blown out with foam, if the gap size is more than 5 mm, then a piece of foam is placed inside the foamed seam. After 4-5 hours, the foam and polystyrene are cut to the level of the insulation plane. This is the most difficult stage in the arrangement of insulation. You need to try to cut and wipe the foam so as to remove the humps, but do not make holes and remove excess foam. At the end, all seams and fungi must be rubbed with glue.

Two-layer insulation of external walls

Sometimes the situation requires the use of more powerful insulation with a foam thickness on the wall of at least 100 mm. Buying such material is quite expensive, and working with it is even more difficult - thick plates are difficult to cut and mount on the outer surface of the walls.

In this case, it would be more rational to lay insulation from several layers. The first foam sublayer is glued in the same way as when arranging conventional insulation. Joints and cracks are also blown out and after a couple of days they are fixed with fungi.

Laying the second layer of wall insulation is even easier than the sublayer - an adhesive solution is poured onto the inner surface, stretched over the surface with a notched trowel and placed on the first row of foam. If the surface of the outer walls has been prepared more or less conscientiously, then the outer layer will lie like a tile in a bathroom, with a minimum of finishing and leveling operations. Of course, for the first layer, the foam must be selected with a surface profiled with vertical grooves.

Applying a protective and leveling plaster layer

Before plastering the foam insulation, a plastic corner with a mesh is laid and fixed on the corners and slopes, in this case the aluminum version is not suitable, you don’t even have to try. Installing the corners is no different from a similar procedure for the interior walls of the house. The corner is aligned vertically with the edges of the grid, stretched and fixed with a small amount of the mixture.

The turn of the reinforcing mesh comes. For reinforcement, a plaster mesh for outdoor work is used, with a density of at least 140 g / m 2. The canvases are rolled out vertically and fixed with a stapler on the upper edge of the insulation. The edges of adjacent canvases overlap by 5-7 cm, after stretching, the overlap line is fixed with a small amount of the mixture.

The fabric laid on top of the insulation is leveled and the leveling layer is laid on the walls. To fix and arrange the protective layer on the foam insulation, a special mixture is used, which is more dense and plastic. You can Ceresit or any other material, but it is to create a protective layer for external plastering.

On top of the grid we lay a thin, several millimeters layer of adhesive mass and smooth it from bottom to top with a spatula, so that between the foam and the grid there is a solution layer of 2-3 mm.

dried reinforced protective layer The plaster has a very uneven surface with streaks and defects, therefore, before laying the leveling layer, it will be necessary to sand the surface. It is best to use two types of sandpaper fixed on a wooden base. The wider the grater, the smoother the outer surface of the walls with insulation, but with a width of more than 25 cm, it becomes simply physically difficult to work. Often the protective layer is wiped with a vibration grinder, other types of equipment are not used because of the risk of damaging the outer surface of the wall and foam insulation.

The next step is to lay a leveling layer on the outer surface of the walls, its thickness is 3-4 mm. It is applied and leveled in the same way as a protective one.

Important! Each layer must be applied and leveled within no more than 48-66 hours in cool weather, in hot weather the time is reduced by 30%. Otherwise, the outer surface becomes very hard, and it will be difficult to overwrite it.

Decorative foam insulation

Before proceeding to the application of decorative plaster or painting, the outer surface of the walls must be primed. If it is planned to lay foam insulation decorative coating, then Ceresit St16, with needle sand filler, is best suited. For painting, the outer surface of the walls can be primed with Ceresit CT17.

Conclusion

It is believed that the most successful option for insulation on polystyrene is one that is not visible from the side, that is, an additional 6-7 cm on the outer walls in no way affect the appearance and design of the building. Sometimes the problem of condensate cannot be solved, for example, for baths or in houses with poor waterproofing of the floor, then siding panels have to be laid on top of the plaster and wall insulation, covering the network of capillaries that have come through the plaster. Often, for wooden or frame-panel houses, the insulation of the outer walls is performed without any glue, on some fungi. In this case, the outer surface of the foam must be melted, primed and painted. water-based paint. Brick imitation lining is used as an external decorative layer, natural stone or wood.

Insulation of the house with polystyrene foam is one of the inexpensive and simple ways keeping warm. This method does not take very much time, but still, when installing the foam, some nuances must be taken into account. The quality of insulation and the durability of the foam may depend on the correct preparation of the surface, the choice of material and the installation.

Necessary materials

First of all, a material such as foam is purchased. Together with it are used:

  • Primer.
  • Tile adhesive.
  • Plaster.
  • Reinforced corners.
  • Fasteners (dowels).

For frame insulation floors and ceilings will additionally need metal or wooden profiles, as well as chipboard sheets.

Tools

For the correct and high-quality fastening of the foam to the walls and ceiling, you need to get a drill. It is desirable to have drills of different sizes for it. The construction level will help to accurately and accurately perform all measurements. A small container is needed to knead the solution, and a spatula is needed to apply it. A construction knife will be used to cut the foam.

Which is better: polystyrene or mineral wool

When choosing a heater, you should always carefully study the characteristics of a particular material. After all, its quality and durability depend on it.

When choosing foam, there is no doubt about its heat and moisture insulating properties. This material is 98% air and completely impermeable to liquids and vapors. Due to this, in the rooms sheathed with such material, heat losses are significantly reduced.

Mineral wool is also great for keeping the heat in the house. With its help, you can insulate any building. It is produced not only in plates, but also in rolls and is quite convenient for installation. However, this material is more susceptible to moisture. The cost of such material also repels many buyers. Therefore, for high-quality and inexpensive insulation of the house, you can completely use foam.

The thickness of the foam for insulation

When choosing foam parameters, you should not dwell on low-quality material with low performance characteristics. For example, density polystyrene foam of 15 kg / m³ is only suitable for insulating the internal walls of a building. And for sheathing the house outside, it is better to buy a more durable one with a density of 25 kg / m³. But to strengthen the slopes of windows and doors, as well as the foundations of the building, it is better to use a density of 35 kg / m³. Due to such high rate It is possible to use thinner sheets.

Thickness foam is selected according to the following principle: if the house needs to be well insulated and protected from strong winds, then it is better to buy material about 15 cm thick. But if the building is located in a warmer climate zone, then you can purchase the most common one, having a thickness of 7 cm, because this type will be cheaper.

If the exterior walls have significant unevenness, then thicker foam can be used to eliminate this problem.

But you can not overdo it when choosing the characteristics of the foam. After all, very thick sheets can lead to technological problems. In some cases, when it is necessary to bypass pipes, it is not possible to use thick sheets. Therefore, it would be more reasonable to purchase foam with a thickness of 5 cm with a density of 35 kg/m 3 than to use 10 cm with a density of 25 kg/m 3. These 2 types are comparable in terms of price and functional characteristics.

But on average, to insulate a house with polystyrene foam, you can be guided by the following rules:

  • The basement, the basement of the building, the slopes of the doors should be insulated with a material 5 cm thick and with a density of 35 kg / m 3.
  • outdoor and internal walls it is better to sheathe with a thickness of 7 cm and a density of 25 kg / m 3.
  • To protect the ceiling and attic from cold and wind, it is suitable for a thickness of 5-7 cm and a density of 15 kg / m 3.

The main thing is to purchase high-quality material that was stored in a dry room. Styrofoam should not be wet and yellow. It should be without any damage.

How to sheathe a house with foam

To cover the house with polystyrene foam, you first need to purchase the right amount of insulation. For this, it is calculated total area exterior walls of the building, door and window openings are taken away and a margin of 10-15% is added. After all, the material may be damaged or the cut pieces may not fit. You should try to make as few seams as possible.

After purchase necessary materials and preparing the basic tools, you can start trimming. For proper conduct works need to follow technology.

How to insulate a house with foam plastic from the outside. Step-by-step instruction

The technology of wall insulation from the outside is as follows:

  • Wall preparation.
  • Primer.
  • Installation of a heater.
  • Puttying.
  • Surface finishing.

Wall preparation begins with cleaning the surface of the old coating, if any. brick or concrete walls thoroughly cleaned of loose plaster, debris and dirt. There should be no falling pieces of walls on the wall. When the wall is not damaged, you can proceed to the primer.

If a hole or crack has formed on the surface, then it is necessary to dilute a small amount of putty and carefully cover the unevenness with a spatula.

If this defect is not eliminated, then it may eventually increase under the insulation, which will lead to the destruction of the wall and damage to the foam.

Stage priming surface is carried out for better adhesion of the insulation to the wall. To do this, a deep penetration primer is purchased in the store and applied with a brush to the wall. This process also gets rid of unwanted dust particles, resulting in a smoother wall.

After such work, you can begin gluing the insulation. The most optimal material for this is tile adhesive. It is convenient in that it is very quickly diluted with water to the desired consistency and allows you to firmly glue the insulation.

Diluted glue is applied with a brush to the wall. It should be spread with a thin layer, after which the prepared foam sheet should be applied for a few seconds.

First you need to mark up to place the sheets on the wall. Using a level on the surface, horizontal lines are drawn along the width of the foam.

Despite the fact that the top of the foam will be covered with a finishing material, it must be laid as evenly as possible. It is necessary to ensure that there is a small gap between the plates, as when laying tiles.

Puttying carried out after the installation of all sheets. This stage consists in sealing the seams. It is allowed to use tile adhesive for these purposes, with which the foam was mounted. You can take a special putty mixture. But in no case can not be sealed with a gypsum mixture. Otherwise, cold bridges may form, which will lead to useless installation of insulation.

After sealing the seams, the wall must be treated with a starting and finishing putty. This is necessary to ensure that the surface is perfectly flat.

It is very important to use reinforced corners at the corners of the building, which sit on the putty. They will strengthen the insulation, and increase resistance to any mechanical stress.

After the wall has dried, it must be treated with sandpaper.

For convenience, you can take a wooden block to which paper is glued. This will greatly simplify the work. Now the surface is ready for processing by any finishing materials. Full information you can read about the beam.

Floor and ceiling insulation

In addition to insulating the walls from the outside, you can use the method of thermal insulation from the roof and from the basement. This will further protect the house from heat loss.

Most optimal way floor insulation is the installation of polystyrene foam from the side of the basement. For this ceiling basement it is cleaned, processed with a mixture for sealing irregularities, primed and insulated with foam. After that, the seams are smeared, a layer of putty and any finishing material is applied.

If it is not possible to install the plates from the basement side, they can be attached indoors. For this:

  • Waterproofing is laid on the wooden floor, bars are stuffed, between which foam plastic is laid, waterproofing, chipboard sheets are stuffed on top.
  • On the concrete base a primer is applied, bars are mounted, sheets are fastened, covered with waterproofing, then with chipboard sheets.

It should be borne in mind that before warming the floor, it must be carefully examined for the presence of cracks, mold and fungus. It is imperative to get rid of this, otherwise the problem will develop under the insulation.

The ceiling is insulated using the same technology: preparation, priming, fixing profiles, foam, sealing, puttying. The insulation can be attached to the installed frame using dowels.

For proper insulation At home, you can listen to the advice of professionals:

  • It is better to start insulation from the roof, then move on to the outer walls and foundation.
  • It is necessary to choose a material of suitable thickness and density so that there are no problems with its installation.
  • For a more durable installation of the foam, you can use umbrella dowels, which allow you to more securely hold the foam.

You can study common mistakes when insulating the facade in the video. Expert advice is provided on how to choose the right material, as well as conduct insulation.

The process of insulating a house with polystyrene foam is quite simple. The material for work has a small weight, which allows it to be glued to the surface without installing rails. But you still need to adhere to the technology, so that the result is of the highest quality.

Since it will be the right and right decision to insulate the house from the outside with foam plastic, especially if the walls of the house let heat out, then we will consider how to do it.

The walls of the house, no matter what they are made of, can let heat out and the house will be cold, and heating bills are high. To eliminate this kind of deficiency, you can insulate the structure. It is important to understand the better to insulate with foam plastic or mineral wool, because in fact these are two different material. In construction, in addition to insulation, it is imperative to use good bricks from the best factories of manufacturers kirpich.expert, choose high-quality Construction Materials for the future home is very important.

How to insulate a private house with foam

Styrofoam is a foamed heat insulator. Due to foaming and subsequent solidification, the air in the pores clogs the space and prevents the heat from the walls from escaping. Styrofoam has many advantages:

1. Moisture resistance - hard fibers do not perceive moisture.

2. Holds its shape well - it is convenient to work with the material due to this.

3. Due to its inorganic origin, living creatures such as rats and mice do not start in it, and microorganisms such as fungi or mold do not live.

4. Due to its light weight, it does not put a load on the structure.

5. It is not subject to temperature changes or combustion due to the presence of fire retardants in the composition.

Due to the fact that polystyrene is not afraid of water, it is most often used if it is necessary to understand the best way to insulate a house with polystyrene foam or mineral wool. After all, the latter is afraid of water and it is necessary to mount it only after carefully isolating the mineral wool from moisture. Also, rats and mice can live in mineral wool, due to the soft fibers of this living creature it is warm there and this does not prevent them from walking on the walls in the literal sense.

Another disadvantage of mineral wool is the need to lay it not in one, but in two layers. Mineral wool is a soft material, it has the ability to decrease in volume, opening the way for heat to the outside.

If you decide to use mineral wool, then you should be prepared for possible problems with this insulator.

Wall preparation

To insulate the walls of the house, you need to prepare the walls, for this they are cleaned from dirt and dust. After that, you need to prime all surfaces on which the insulation will be laid. This is a necessary moment if it is important how to properly insulate the house with foam plastic from the outside. Thus, good adhesion of the walls of the building with the heat insulator is achieved.

Uneven walls are best leveled before applying insulation. To do this, cracks and recesses are filled with mortar and allowed to dry well.

Also, many are interested in whether it is possible to insulate wooden house styrofoam? Yes, of course you can. But in this case, you can do without glue, as well as a primer, and it will be necessary to mount a special frame, where the insulation will be laid. But mounting on fungi is best done for secure fastening.

How to insulate a wall from the outside with foam

After priming, the wall must be allowed to dry, it takes a little time. During this time, you need to prepare the glue, since it does not matter with which foam to insulate the house from the outside, it is important to glue it to the wall. This is necessary so that the insulation does not roll down. Therefore, in this regard, it is more convenient to work with polystyrene, due to its rigidity it is easy to glue it to the walls, and it does not roll down like mineral wool. If the question is what is better to insulate the walls with polystyrene foam or mineral wool, then without a doubt it is better to opt for foam plastic. Since the work will move faster and the quality of the wall is much higher.

After preparing the glue and insulation, it is necessary to attach a metal starting bar to the lower edge of the walls. It will help the bottom layer of the heat insulator stay in place.

Since it is impossible to insulate a house with foam plastic without glue, you need to correctly apply the glue. It can be applied in different ways:

1. If the wall is uneven, the glue can be applied directly to the wall, it is better to do it gradually so that the glue does not dry out. Thus, the composition will fill in the bumps.

2. Also, it makes sense to apply glue directly to the heat insulator. This method will be advantageous if the question is how to properly insulate walls with large irregularities with foam plastic.

3. You can apply special glue from a can. It is applied directly to the foam and pressed against the wall.

After fixing the heat insulator to the glue, it takes time for the glue to dry. According to the technology of how to insulate the facade with foam plastic, you need to screw the foam plastic plates onto special dowel-fungi. They have a large hat and with this hat they press against the wall.

For dowel-nails, you need to drill a hole equal to the thickness of the foam plus 45 mm from the recess into the wall plus 1 cm. The diameter of the hole should be equal to the diameter of the nail. After that, a nail is hammered.

By the number of dowel-nails, the following values ​​\u200b\u200bare taken: for each corner of the plate, one nail plus 1 nail in the center of the insulation. For corner elements, you need to take 6 pieces for each plate. After screwing in the nails, you need to glue all the joints, as well as the places of the nails, with special aluminum tape. In the technology of whether it is possible to insulate the house with foam plastic from the outside, this step will allow you to remove the cold bridges that occur at the joints and places where nails are driven in. After these works, the house can be finished with exterior cladding.

Is it possible to insulate the house with foam

There is still debate about whether it is possible to insulate walls with foam plastic, because it has a low vapor conductivity value. This means that the house walls can become damp and begin to rot. To avoid this, it is necessary to leave small areas that will allow the wall to breathe. But, when gluing, this option is not possible. So, it makes sense to leave unfinished areas that give access to the wall from above. At the same time, it is necessary to ensure that water does not get into these areas. It is in this way that the question of how to properly insulate a wall with polystyrene is solved.

For wooden or frame walls making a gap between the wall and the tree is simple, just build a double crate.

The use of a vapor barrier membrane is also a stumbling block for many builders on the issue of how to insulate walls with foam. One thing they say is that the additional waterproofing that occurs with the use of the film will not hurt. Others believe that this is superfluous, since the technology of how to insulate walls with foam plastic does not provide for the use of pairs of a windproof membrane.

Styrofoam thickness

When insulating a house, you should choose the thickness of the insulation. This point is very important because:

1. Too thin a layer will not give the desired insulation.

2. Too thick a layer will increase the load on the structure with its weight, and also, it simply will not justify the spent expenses.

Therefore, it is important to understand how thick the foam insulates the house and choose best option. If the house is insulated according to the project, which was compiled by knowledgeable people, then this indicator can be found in the documents. With an independent decision on the issue of how to properly insulate a house with polystyrene foam, you will have to look for special laws regulating this indicator. But you can do it easier and ask around experienced specialists. As a rule, many builders note that a foam plastic thickness of 10 cm is enough for high-quality insulation of a house. For frame house it is better to double this figure, especially if they plan to live in the house permanently.

Additional pros and cons

When insulating walls, the appearance of additional qualities cannot be noted. Styrofoam is also a good sound insulator, which means that an insulated house will not let in extraneous noise from the street into the house.

Also, the foam is not afraid of temperature changes, which is very important in the northern regions, where frosts reach strong levels. But open insulation is afraid of the action of the sun, since ultraviolet rays destroy this material. Therefore, immediately after insulation, it is necessary to produce its facing.

Styrofoam, due to its moisture resistance, can be used in warming the walls of a steam room. Sheets from the side of the room must be glued with a special metallized adhesive tape, it will reflect heat inward, so that the room will remain warm longer.

These are all the pros and cons of foam. In any case, it is up to the owner to decide whether it is worth insulating the house with this material, but the number of pluses shows that foam insulation will not hurt.