How the facade of the house is insulated with expanded polystyrene, what are the pros and cons of this method, the stage-by-stage technology of mounting plates on the walls. Insulation of facades with expanded polystyrene is one of the most effective methods of thermal insulation. Thanks to the excellent technical characteristics of the material, you can significantly save on heating the building. In addition, expanded polystyrene is lightweight, which greatly simplifies installation.
Features of work on thermal insulation of facades with expanded polystyrene
Nowadays, there are a large number of materials on the construction market that can be used for thermal insulation. The most popular and demanded is expanded polystyrene. This material is distinguished by such qualities as high strength, low thermal conductivity, ease of processing, low price.
It is necessary to distinguish between two materials that are used for thermal insulation - foam and expanded polystyrene. They are often confused, but there are significant differences. First of all, they relate to production technology.
In the case of expanded polystyrene, this is extrusion, that is, transformations do not take place in granules separately (as in foam plastic), but throughout the entire thickness of the substance. Therefore, expanded polystyrene has inseparable intermolecular bonds. This contributed to the improvement of the technical characteristics of the material and a decrease in thermal conductivity. Expanded polystyrene is more durable and dense than polystyrene foam.
The method of thermal insulation with expanded polystyrene is well suited for houses built of brick, shell rock, reinforced concrete, cinder block.
The technology of insulating walls of a house with expanded polystyrene consists of several stages. All of them are mandatory, since violation of the norms will negatively affect the quality of work and such thermal insulation will not last long. It is necessary to insulate the house with this material outside and only in warm and dry weather. As a rule, installation work is carried out in late spring or early autumn. Equally bad for unprotected polystyrene foam is direct sunlight and precipitation. They can reduce the thermal insulation properties of the material. There are several ways to insulate walls with expanded polystyrene. The choice of method depends on the state of the material. If it is stabilized, that is, in slabs, then it is quite possible to attach it to the facade yourself. If it is sprayed, then the process of thermal insulation with its help should be entrusted to professionals who have special equipment for its application.
The thickness of polystyrene foam should be selected in accordance with the thickness of the walls of the building. There is such a pattern:
- With a wall thickness of 1 brick, 50 mm slabs are used.
- The walls of one and a half bricks are covered with a layer of expanded polystyrene 38-40 millimeters.
- With walls of two bricks, you can take polystyrene foam 32 mm thick.
- For walls 2.5 bricks thick, a 29 mm heat insulator is suitable.
Advantages and disadvantages of facade insulation with expanded polystyrene
For insulation of facades with expanded polystyrene, it is recommended to choose special sheets that have been treated with flame retardant impregnations.
Such thermal insulation has a number of significant advantages:
- Extruded polystyrene foam boards are easy to work with as they are lightweight and small in size. It is quite possible for one person to insulate a house without helpers.
- Plates can be processed by any means at hand - they are easy to cut and bend well enough.
- Insulation of the house from the outside with expanded polystyrene ensures that the dew point is located outside the load-bearing wall. In this case, moisture will not accumulate, and the walls will freeze.
- The facade of the building, insulated with expanded polystyrene, will act as a temperature stabilizer in terms of thermal inertia. Thus, its daily fluctuations will not affect the microclimate inside the house in any way.
- External thermal insulation with expanded polystyrene will not affect the area of the rooms.
- Walls insulated with this material will not be negatively affected by moisture from the outside, since the heat insulator is hydrophobic.
- The method of thermal insulation with expanded polystyrene is environmentally friendly. The material does not emit harmful toxic chemicals. You can work with him without using personal protective equipment.
- This surface is durable. If you cover expanded polystyrene with a protective decorative layer, then it can last up to 80 years without losing its properties.
As for the disadvantages of the facade insulation method using expanded polystyrene plates, only the relative flammability of the material should be highlighted. Polymeric additives, which are included in the composition, are "responsible" for the increased fire hazard. However, if this heat insulator is used in accordance with fire safety requirements and the rules for its installation, then the danger can be easily avoided.
Note that the combustion temperature of expanded polystyrene is +491 degrees Celsius. This is more than 2 times higher than paper or wood. In addition, the fire resistance of the material is also determined by its combination with other building materials and the presence of protective coatings.
The technology of insulating the facade of the house with expanded polystyrene
Expanded polystyrene of the C-25 brand is optimally suited for insulation of facades. It is quite dense and has better thermal insulation characteristics. And a material with a density of 15 kilograms per cubic meter is not able to provide the necessary structure for thermal insulation of the facade. In addition, it can be damaged during operation. It is necessary to fix the plates strictly in stages.
Preparatory work before installing polystyrene foam
First of all, it is necessary to carry out a complete dismantling from the facade of storm drains, ventilation grilles, ebbs, street lighting devices, climate control structures, and decor. It is also necessary to remove the remnants of the previous finish - plaster, paint, tiles. After that, we inspect the surface for flaws and deviations from the vertical line. To fix the sheets of expanded polystyrene, it is not necessary to achieve perfect evenness of the walls. But large differences still have to be leveled with plaster. Otherwise, moisture will accumulate in the grooves. It will negatively affect the condition of the heat insulator. If the outer wall has a loose finishing layer, then it should be strengthened. To do this, apply a deep penetrating primer (for example, CT 17) to the surface and cover it with a layer of plaster. Extruded polystyrene foam also needs preparation. It has a smooth surface which must be porous prior to installation. To do this, we process one of the sides of the plate with a needle roller. It will create small notches. If it is not at hand, then you can use a construction knife. In the process of work, we need such tools: a drill, a hammer, a construction knife, several spatulas, a building level or a laser level, a plumb line. In addition, you need to prepare the following materials: expanded polystyrene plates of different thicknesses (for the facade up to 50 millimeters, for slopes - up to 30 millimeters), fasteners (plastic nails, wide-hat dowels, mounting glue and foam, reinforced mesh, primer, basement profile.
Installation of ebb tides and thermal insulation of slopes
Before starting the process of insulating the facade of the house with expanded polystyrene, it is necessary to install ebb tides and insulate the slopes. Please note that the length of the ebb must exactly match the thickness of the polystyrene foam and plaster layers, and also take into account the additional play of two to three centimeters. To insulate window slopes, we use thin sheets of expanded polystyrene from two to three centimeters thick. The heat insulator should protrude a centimeter from the material covering the walls. This stock will make it possible to carry out high-quality joining of the material that is installed on the slopes with the covering of the walls.
We fasten the sheets with assembly glue. To do this, apply it with spots or evenly coat the material around the perimeter using a comb spatula. The latter method is good in cases where the surface of the facade is perfectly flat. We also apply a thin layer of the mixture to the wall. We apply to the marked points and press down slightly.
Installation of expanded polystyrene on the building facade
In addition to assembly glue, when fixing expanded polystyrene plates to the facade, you will also need wide-hat dowels.
We carry out work on the following technology:
- In the lower space of the wall, set the starting profile. He will have to keep the first sheet of polystyrene foam on the glue and will not allow him to move.
- We apply glue to the facade, as well as pointwise to the heat insulator plate. At this stage, you can slightly adjust the unevenness and differences in the wall by changing the thickness of the adhesive layer.
- We press the sheets tightly to the surface and joints to each other. We glue expanded polystyrene with a horizontal displacement only.
- It takes about three days for the material to fully adhere to the wall. At the end of this period, we fix the slabs with dowels. This will help prevent the sheets from being ripped off by strong gusts of wind. The length of the fastener should be calculated taking into account the immersion into the wall of at least five centimeters. We place the dowels in the center of the sheet and at the joints.
- We prepare holes with a diameter of up to one centimeter. We make the depth more than the length of the fastener.
- We install the dowel in the groove and drive a plastic nail into it.
- The distance between the expanded polystyrene plates, which exceeds 5 millimeters, is filled with polyurethane foam.
- If the joints are more than 20 millimeters, then we close them with strips of heat insulator and then foamed.
- After five hours, the foam will completely harden. Now we cut off its excess with a construction knife.
- We rub over noticeable irregularities on the surface of the material or at the joints with a special float, which is intended for expanded polystyrene.
- We clean the nail heads and putty. Sand the dried putty with medium-grain sandpaper.
If you are insulating the facade with extruded polystyrene foam in two layers, then it is recommended to fix the plates with intersecting seams - transverse and longitudinal. This will prevent foam from the upper layer to the lower one.
Fixing the reinforcing mesh to the facade
The facade of the insulated building must be covered with a reinforcing mesh. For the main surface, we use a rigid dense mesh with an indicator of 150 grams per square meter. We use softer material for corners, slopes and decorative elements. We fix the mesh with mounting glue and perforated corners.
We carry out the work in this order:
- First of all, we attach the reinforcing layer to the slopes and corners of the walls. To do this, cut into strips of 30 centimeters. When preparing the material, you need to take into account the height of the openings.
- We bend the strip twice.
- Apply assembly glue to the corner of the house using a wide spatula.
- Press the mesh tightly to the slope or corner and smooth it with a rubber spatula.
- We cover the walls with small pieces of mesh.
- Apply the glue mixture with a thickness of about 3 millimeters.
- We apply the material so that about 10 centimeters of the surface lies on the expanded polystyrene untreated with glue.
- Smooth the mesh with a rubber spatula from the center to the edge.
- If necessary, add glue so that it evenly covers the mesh.
- On uncoated areas of expanded polystyrene, apply the solution and overlap the next strip.
- After the glue has hardened, we grout it with fine-grained sandpaper.
Finishing of the insulated facade
Before proceeding with the finishing work, some preparatory work should be done. Apply a leveling layer to the reinforced polystyrene foam. For this we use a finishing putty and a large spatula. After drying, we grind the layer with fine-grain sandpaper. We ground the facade of the building.
We apply decorative paint or plaster on a dry wall surface. Note that decorative finishing materials used for outdoor work should be based on polymers that are resistant to any weathering. How to insulate the facade with expanded polystyrene - watch the video:
The technology of insulating the facade with expanded polystyrene is actively used in our area, since this material has excellent thermal insulation qualities, which makes it the optimal insulation in cold winters. In addition, it can be easily installed on exterior walls by even one person using the available tools.
